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Data 8: Foundations of Data Science

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Acknowledgements

This course is adopted from Data 8, “The Foundations of Data Science” course taught to first-year students at UC Berkeley. All materials for the course, including the textbook and assignments, are available for free online under a Creative Commons license. Textbook: Computational and Inferential Thinking: The Foundations of Data Science is a free online textbook that includes interactive Jupyter notebooks and public data sets for all examples. Course Materials: The Embedded Demo, Lab and Homework Notebooks as well as linked references all come from publicly available materials used in the course during the Spring 2020 semester at UC Berkeley as well as materials used in the self-paced Data 8X course on EdX .

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Data 8: Foundations of Data Science

Foundations of Data Science: A Data Science Course for Everyone

What is it?

Foundations of Data Science (Data C8, also listed as COMPSCI/STAT/INFO C8) is a course that gives you a new lens through which to explore the issues and problems that you care about in the world. You will learn the core concepts of inference and computing, while working hands-on with real data including economic data, geographic data and social networks.

Who is it for?

The course is designed for entry-level students from any major. It is designed specifically for students who have not previously taken statistics or computer science courses.

Does it satisfy requirements?

Yes, it satisfies the L&S Quantitative Reasoning requirement, as well as the statistics requirement in most departments that require it. But unlike other statistics courses, it also introduces you to computer programming. Unlike other computer science courses, it gives you a chance to work hands-on with real data and tackle real-world issues.

What are the prerequisites?

Why should i take this course.

In a world in which we’re surrounded by data, this course enables you to combine that data with Python programming skills to ask questions and explore problems that you encounter in any field of study, in a future job, and even in everyday life.

What kind of support is available if I need help?

Lots of support and tutoring are available. In weekly labs, you’ll get hands-on practice. Small-group tutoring sessions are also available, and course staff strongly encourage you to take advantage of their office hours. The Data Scholars program provides community and support to underrepresented and nontraditional students.

What is the format?

The course includes lectures, a required weekly lab, homework, and projects in which you’ll tackle real-life issues using real data. Connector courses connect Data 8 to many areas, if you want to take one at the same time or later.

What does it cover?

The course teaches you all the key ideas of an introductory statistics class, in a new, modern, hands-on way. It weaves in contextual issues like data privacy and bias. At the same time, it gives you a powerful understanding of key ideas in computing.

Data 8 is a great class if you want to understand data in the world around us, or use these tools in your own major. It's also the best foundation for going on in data science.

What do students say about it?

"It's very hands-on -- I was able to go through the data myself, and ask questions I was curious about. It really cemented the idea for me that data tells a story and can shed light on things that I never considered before.”

“Taking data science really sets you apart and makes you more valuable. It lets you ask questions and find answers in a way that most other students can’t. Data helps you communicate, no matter whether your field is technical or non-technical.”

“One of the things I most enjoy about data science is the diversity -- my classmates range from English majors to bio majors to fellow computer science majors -- all looking at data from our different perspectives.”

“I truly came out of this class loving statistics, and I intend to explore more of the world of data science. As someone who is majoring in the social sciences (Political Science) I'm grateful to you and the staff for making this course accessible to all majors across campus.”

“I enjoy that you learn by doing -- you look at the data yourself, analyze it, ask questions, and draw conclusions.”

How can I get more information?

All the course materials are online. Just visit data8.org .

Unit 8: Bivariate Data 

Scatter Plots and Association Class Notes

Scatter Plots and Association (Student Handout 1)

Scatter Plots and Association (Homework 1)

Constructing and Predicting Scatter Plots Class Notes

Constructing Scatter Plots (Student Handout 2)

Constructing Scatter Plots (Homework 2)

Scatter Plots and Predictions (Student Handout 3)

Scatter Plots and Predictions (Homework 3)

Trend Line Equations Class Notes

Trend Line Equations (Student Handout 4)

Trend Line Equations (Homework 4)

Trend Line Equations (Homework 4) Solutions

Two-Way Tables (Student Handout 5)

Two-Way Tables (Homework 5)

Relative Frequency (Student Handout 6)

Relative Frequency (Homework 6)

Relative Frequency (Homework 6) Solutions

Scatter Plots and Data Study Guide

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Over 20 aftershocks hit New York, NJ following 4.8 earthquake according to USGS

A 4.0 magnitude aftershock hit 37 miles west New York City in New Jersey around 6 p.m. Friday. According to the United States Geological Survey it was felt as far away as Long Island, where there were reports of houses shaking.

New York City’s emergency notification system  alerted residents  to the aftershock minutes later, urging people to remain indoors and call 911 if injured. Hochul said  there were no reports of serious damage after the aftershock, and officials were continuing to assess critical infrastructure.

There have been over 20 aftershocks since the initial earth quake according to the USGS website as of 2 a.m. April 6.

Earthquake and aftershock timeline

• Magnitude 1.8: Near Gladstone, NJ at 1:07 a.m. April 6
• Magnitude 1.5: Near Gladstone, NJ at 8:51 p.m.
• Magnitude 1.8: Near Whitehouse Station, NJ at 8:39 p.m.
• Magnitude 1.5: Near Whitehouse Station, NJ at 7:39 p.m.
• Magnitude 1.9: Near Bedminster, NJ at 7:10 p.m.
• Magnitude 1.9: Near Bedminster, NJ at 6:16 p.m.
• Magnitude 4.0: Near Gladstone, NJ at 5:59 p.m.
• Magnitude 1.9: Near Whitehouse Station, NJ at 4:21 p.m.
• Magnitude 2.0: Near Whitehouse Station, NJ at 4:13 p.m.
• Magnitude 2.0: Near Whitehouse Station, NJ at 3:58 p.m.
• Magnitude 1.8: Near Califon, NJ at 2:40 p.m.
• Magnitude 2.2: Near Whitehouse Station, NJ at 1:32 p.m.
• Magnitude 1.9: Near Califon, NJ at 1:21 p.m.
• Magnitude 2.0: Near Chester, NJ at 1:18 p.m.
• Magnitude 2.0: Near Chester, NJ at 1:14 p.m.
• Magnitude 1.8: Near Bedminster, NJ at 12:49 p.m.
• Magnitude 1.8: Near Bedminster, NJ at 12:31 p.m.
• Magnitude 2.0: Long Valley, NJ at 11:49 p.m.
• Magnitude 1.8: Califon, NJ 11:37 a.m.
• Magnitude 1.9: Califon, NJ at 11:33 a.m.
• Magnitude 2.0: Whitehouse Station, NJ at 11:20 a.m.
• Magnitude 4.8: Near Whitehouse Station, NJ at 10:23 a.m.

The aftershock Monday evening was at least the third that USGS recorded after the quake struck.

As of Friday afternoon, the USGS  aftershock forecast  predicted a 36% chance of aftershocks at a 3.0 magnitude or higher, an 8% chance of aftershocks at a 4.0 magnitude or higher, and a 1% chance for aftershocks at a magnitude of 5.0 or higher over the next week.

USGS scientists said informal observations can be a big help in understanding earthquakes, especially in a region where they’re less common.

“We encourage people to fill out the  ‘Did You Feel It?’ reports  on our website,” said Sara McBride, a scientist with the USGS Earthquake Hazards Program. “This citizen science project is critical in terms of building our knowledge around earthquakes.”

By midafternoon on Friday, the agency said it had received more than 161,000 reports, and extrapolated that the quake had been felt by millions of people. McBride acknowledged that earthquakes can be nerve-wracking for people who don’t live in seismologically active regions, and said knowledge is power in combatting that discomfort.

“The best thing you can do to relieve any unsettling feelings you might have is to learn how to protect yourself during shaking and how to prepare for earthquakes in the future,” she said.

USA Today contributed to this report

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This year, colleges must choose between fast financial aid offers, or accurate ones

Sequoia Carrillo

Countless prospective college students are eager to commit to colleges, acceptances in hand, but are stuck waiting for one last piece of the puzzle: their college financial aid package. Those offers are coming later than normal this year, due to the troubled launch of the U.S. Education Department's new federal student aid form, or FAFSA.

Some institutions are doing anything they can to get those offers out as soon as possible – even if it means they aren't a guarantee. For example, Cal Poly Pomona has decided to send "provisional" aid offers for now, with final offers coming by the time students officially start classes.

This year it's a slow crawl to financial aid packages for students

"The goal is to have these done, you know, for sure before school starts," says Jeanette Phillips, head of financial aid there. Phillips says other financial aid administrators in the California State University system, the largest in the country, have decided to do the same thing.

With students and families eagerly awaiting the results of their FAFSA applications, college financial aid offices are in a tough position: They need to send aid offers out as soon as possible to give students time to weigh their options, but they also don't yet trust the FAFSA data the Education Department is sending them.

That's because the data has been "riddled with errors or incompletions," says Justin Draeger, the president and CEO of the National Association of Student Financial Aid Administrators.

To navigate this dilemma, Draeger says, "different schools are trying different tactics."

"Some schools are going to send out provisional or estimated aid offers as soon as they can. Other schools aren't able to sort through the data. They feel like they are stuck until they get more information."

At Oregon State University, the financial aid office is taking its time. Keith Raab, the head of financial aid at OSU, tells NPR they've had the conversation about provisional offers, but ultimately decided against it.

Exclusive: The Education Department says it will fix its $1.8 billion FAFSA mistake

"Our experience has been that those mostly add to confusion instead of making things more clear," he says. "Students and families don't understand why things change and we don't want to add to their stress."

Instead, they're trying to be transparent about timelines, and sending frequent updates to students and parents who have already submitted their forms.

Towson University, outside Baltimore, is taking a similar approach. Boyd Bradshaw, who runs the admissions and financial aid offices there, says he wants families to know the school will be flexible.

"We're going to work individually with each student to make sure that their financial aid package doesn't deter their attendance," he says.

Compounding FAFSA delays have forced colleges to act

The revamped FAFSA got off to a slow start last year, debuting three months late , and pushing back the timeline for colleges to start processing student financial aid offers. Those offers were further delayed while the department worked to fix a FAFSA math error that failed to take inflation into account. The department said it would start sending financial aid data to schools in the first half of March, just weeks before the traditional college commitment deadline of May 1.

Schools did start to receive student data in March, but in many cases, it was only by the handful : single-digit numbers of student files to start, then a few hundred, then a few thousand. The department finally cleared the backlog of applications last Friday, but shortly after, it announced that about 20% of the data was impacted by other errors.

A new FAFSA setback means many college financial aid offers won't come until April

The department said it "recognizes how important it is that schools and states have the information they need to extend financial aid offers and that families have the information they need to make critical education decisions."

In an email to NPR, a department spokesperson said they are working to make it easier for students to apply for and receive financial aid.

The compounding delays have pushed many schools – including George Mason University in Northern Virginia and Colorado State University – to shift their commitment deadlines to mid-May or June.

And while the department is working to fix many of the errors, one is still causing difficulty for some mixed-status families, or families where the students are citizens, but the parents or guardians are not. For a while it wasn't possible for parents without a social security number , which many non-citizens don't have, to fill out the new form. In mid-March the department said they had fixed the problem, but was aware of continued difficulties for some students.

Some students are still locked out

Georgina García Mejía, a senior at Bethesda-Chevy Chase High School in the Maryland suburbs outside Washington, D.C., has been trying to submit her FAFSA since the beginning of February.

"I try like, four times a week," she says. She submits the form over and over hoping for a different response. García Mejía has citizenship, but her mom does not, so she falls into that bucket of students from mixed-status families who are still locked out.

Yet another FAFSA problem: Many noncitizens can't fill it out

García Mejía hopes to go to Towson University, where she's already been accepted, to stay close to her family and work toward a nursing degree. Towson's commitment deadline is May 15.

"I'm scared that the deadline is coming really soon," she says. "And I won't be able to get the help that I want."

The only guidance her counselors can give her is to call the FAFSA helpline and see if someone picks up. She says she hasn't been calling every day, but definitely most days. "I'm never able to get to someone."

Boyd Bradshaw, at Towson, says he's been hearing from a lot of mixed-status students like García Mejía.

"We've heard the same story," he says. "And there's no real answer to why it works for some and not for others."

His advice for mixed-status applicants is to try the FAFSA helpline first, and if that doesn't work, reach out to Towson's financial aid office.

"We're not going to shut our doors, particularly with students who are having these challenges."

His office is hoping to get aid offers out to students by the end of April. Towson has already extended its commitment deadline once, and Bradshaw says he's not opposed to extending it again, if the errors continue.

"What I can tell families: 110% we will be flexible after May 15," he says.

This year, everyone is flexible, whether they want to be or not.

4.8 magnitude earthquake struck New Jersey Friday morning. What caused it and what's next

In the aftermath of a 4.8 magnitude earthquake that rocked New Jersey, Delaware and the surrounding region, many questions still linger. What caused the earthquake? Was it expected? And just how likely is it to happen again?

Like all earthquakes, Friday morning's shaking was caused by movement in the Earth's crust. These movements are most common along active fault lines, according to Delaware Geological Survey Director David Wunsch, but earthquakes occurring outside of these areas is not unheard of.

Friday morning's quake measured in at a 4.8 magnitude. But even with the quake being too small to cause any major damage, Wunsch said it was still one of the largest earthquakes in the region in decades.

NJ earthquake: 4.8 magnitude earthquake in New Jersey felt in Delaware, along the East Coast. What we know

Was that an earthquake?: 'Dog was acting wacky.' Social media reacts after earthquake sends shocks to Delaware

What caused 4.8 magnitude earthquake in New Jersey?

The Earth's crust — the outermost shell of the planet — often adjusts over time, Wunsch said. This settling and changing of the crust is what causes earthquakes. It's also what makes quakes in areas without active fault lines unexpected.

However, the fact that Friday morning's earthquake could be felt throughout the region was not random. The quake's epicenter — about 3.1 miles northeast of Lebanon, New Jersey — is located in the state's Piedmont region. This is an area where rocks and crystals are very old, Wunsch said. They are also very efficient at transferring energy, which may have led to the widespread effects.

Northern New Jersey is also home to some failed rift valleys, Wunsch said. These are spots where the continents tried to split apart hundreds of millions of years ago, and often have old faults associated with them. Wunsch said it's possible that activity along one of these rifts could have caused Friday's earthquake, but it's "hard to know" until experts are able to analyze the data more thoroughly — a process that usually takes a few days.

What comes next following the NJ earthquake?

The smaller size of the earthquake means that it's unlikely that anyone will be able to feel the aftershocks. Wunsch said people near the epicenter may see some "rattling," but otherwise only sensors will be able to pick up the waves.

Wunsch added that there's no data to signify that similar earthquakes are likely to occur in the region going forward.

"They have us in a pretty low-risk zone here," Wunsch said.

Send story tips or ideas to Hannah Edelman at [email protected]. For more reporting, follow them on X at  @h_edelman.

Watch CBS News

What customers should know about AT&T's massive data breach

By Khristopher J. Brooks

Edited By Anne Marie Lee

Updated on: April 2, 2024 / 5:38 PM EDT / CBS News

Millions of current and former AT&T customers learned over the weekend that hackers have likely stolen their personal information and are sharing it on the dark web . 

AT&T on Saturday said it doesn't know if the massive data breach "originated from AT&T or one of its vendors," but that it has "launched a robust investigation" into what caused the incident. The data breach is the latest cyberattack AT&T has experienced since a leak in January of 2023 , that affected 9 million users. By contrast, Saturday's much larger breach impacts 73 million current and former AT&T account holders. AT&T has seen several data breaches  over  the years that range in size and impact. 

The data breach prompted an Ohio man to file a class-action lawsuit against AT&T, accusing the telecommunications giant of negligence and breach of contract. Lawyers representing Alex Petroski of Summit County, Ohio, argued that the cyberattack could have been avoided and that AT&T's security failed to protect customer data. 

Until more details of AT&T's investigation arise, here's what customers should know about the most recent data breach.

How many people were impacted by the AT&T data breach?

AT&T said the breach on Saturday affects about 7.6 million current and 65.4 million former AT&T customers. 

What type of information was taken from AT&T?

AT&T said Saturday that a dataset found on the  dark web contains information such as Social Security and passcodes. Unlike passwords, passcodes are numerical PINS that are typically four-digits long. Full names, email addresses, mailing addresses, phone numbers, dates of birth and AT&T account numbers may have also been compromised, the company said. The impacted data is from 2019 or earlier and does not appear to include financial information or call history, it added.

Was my information affected by the AT&T data breach?

Consumers impacted by this breach should be receiving an email or letter directly from AT&T about the incident. The email notices began going out on Saturday, an AT&T spokesperson  confirmed .

What has AT&T done so far to help customers?

Beyond notifying customers, AT&T said that it had already reset the passcodes of current users. The company also said it would pay for credit-monitoring services where applicable.

What's the latest with AT&T's investigation into the breach?

AT&T hasn't disclosed details about its investigation into the data breach, but it is likely to be time-consuming and costly, according to Kevin Powers, the founding director of the Master of Science in Cybersecurity Policy and Governance Programs at Boston College.

The company will most likely bring in outside computer forensics specialists who will work with its on-site IT staff to determine exactly when and how the hackers got into the customer account information system, Powers said. But identifying the hackers' path of entry will be a big challenge for such a large company.

"You don't know where it came in from," Powers told CBS MoneyWatch, referring to the source of the breach. "It potentially could be from a customer or it could have been done from one of their outside contractors or someone else along their supply chain."

In addition, AT&T will have to scrub any malware out of the software that runs its customer account system, while also keeping the system running for customers who weren't impacted, he said. All these steps will have to be shared with lawyers, the outside consultants, and likely officials from the Federal Trade Commission. 

What's the best way to protect my personal information? 

Start by freezing your credit reports at all three major agencies — Equifax, Experience and TransUnion. Then sign up for 24-7 credit monitoring and enable two-factor authentication on your AT&T account, said WalletHub CEO Odysseas Papadimitriou, a former senior director at Capital One.

If you receive a notice about a breach, it's a good idea to change your password and monitor your account activity for any suspicious transactions. The Federal Trade Commission offers free credit freezes and fraud alerts that consumers can set up to help protect themselves from identity theft and other malicious activity.

—The Associated Press contributed to this report.

Khristopher J. Brooks is a reporter for CBS MoneyWatch. He previously worked as a reporter for the Omaha World-Herald, Newsday and the Florida Times-Union. His reporting primarily focuses on the U.S. housing market, the business of sports and bankruptcy.

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4.1 Probability Distribution Function (PDF) for a Discrete Random Variable

Suppose that the PDF for the number of years it takes to earn a bachelor of science (B.S.) degree is given in Table 4.31 .

• In words, define the random variable X .
• What does it mean that the values 0, 1, and 2 are not included for x in the PDF?

4.2 Mean or Expected Value and Standard Deviation

A theater group holds a fund-raiser. It sells 100 raffle tickets for $5 apiece. Suppose you purchase four tickets. The prize is two passes to a Broadway show, worth a total of $150.

• What are you interested in here?
• List the values that X may take on.
• Construct a PDF.
• If this fund-raiser is repeated often and you always purchase four tickets, what would be your expected average winnings per raffle?

A game involves selecting a card from a regular 52-card deck and tossing a coin. The coin is a fair coin and is equally likely to land on heads or tails.

• If the card is a face card, and the coin lands on heads, you win $6.
• If the card is a face card, and the coin lands on tails, you win $2.
• If the card is not a face card, you lose $2, no matter what the coin shows.
• Find the expected value for this game (expected net gain or loss).
• Explain what your calculations indicate about your long-term average profits and losses on this game.
• Should you play this game to win money?

You buy a ticket to a raffle that costs $10 per ticket. There are only 100 tickets available to be sold in this raffle. In this raffle there are one $500 prize, two $100 prizes, and four $25 prizes. Find your expected gain or loss.

Complete the PDF and answer the questions.

• Find the probability that x = 2.
• Find the expected value.

Suppose that you are offered the following deal: You roll a die. If you roll a six, you win $10. If you roll a four or five, you win $5. If you roll a one, two, or three, you pay $6.

• What are you ultimately interested in here (the value of the roll or the money you win)?
• Over the long run of playing this game, what are your expected average winnings per game?
• Based on numerical values, should you take the deal? Explain your decision in complete sentences.

A venture capitalist, willing to invest $1,000,000, has three investments to choose from: The first investment, a software company, has a 10 percent chance of returning $5,000,000 profit, a 30 percent chance of returning $1,000,000 profit, and a 60 percent chance of losing the million dollars. The second company, a hardware company, has a 20 percent chance of returning $3,000,000 profit, a 40 percent chance of returning $1,000,000 profit, and a 40 percent chance of losing the million dollars. The third company, a biotech firm, has a 10 percent chance of returning $6,000,000 profit, a 70 percent of no profit or loss, and a 20 percent chance of losing the million dollars.

• Construct a PDF for each investment.
• Find the expected value for each investment.
• Which is the safest investment? Why do you think so?
• Which is the riskiest investment? Why do you think so?
• Which investment has the highest expected return, on average?

Suppose that 20,000 married adults in the United States were randomly surveyed as to the number of children they have. The results are compiled and are used as theoretical probabilities. Let X = the number of children married people have.

• Find the probability that a married adult has three children.
• In words, what does the expected value in this example represent?
• Is it more likely that a married adult will have two to three children or four to six children? How do you know?

Suppose that the PDF for the number of years it takes to earn a bachelor of science (B.S.) degree is given as in Table 4.34 .

On average, how many years do you expect it to take for an individual to earn a B.S.?

People visiting video rental stores often rent more than one DVD at a time. The probability distribution for DVD rentals per customer at Video to Go is given in the following table. There is a five-video limit per customer at this store, so nobody ever rents more than five DVDs.

• Describe the random variable X in words.
• Find the probability that a customer rents three DVDs.
• Find the probability that a customer rents at least four DVDs.
• At which store is the expected number of DVDs rented per customer higher?
• If Video to Go estimates that they will have 300 customers next week, how many DVDs do they expect to rent next week? Answer in sentence form.
• If Video to Go expects 300 customers next week, and Entertainment Headquarters projects that they will have 420 customers, for which store is the expected number of DVD rentals for next week higher? Explain.
• Which of the two video stores experiences more variation in the number of DVD rentals per customer? How do you know that?

A “friend” offers you the following deal: For a $10 fee, you may pick an envelope from a box containing 100 seemingly identical envelopes. However, each envelope contains a coupon for a free gift.

• Ten of the coupons are for a free gift worth $6.
• Eighty of the coupons are for a free gift worth $8.
• Six of the coupons are for a free gift worth $12.
• Four of the coupons are for a free gift worth $40.

Based upon the financial gain or loss over the long run, should you play the game?

• Yes, I expect to come out ahead in money.
• No, I expect to come out behind in money.
• It doesn’t matter. I expect to break even.

A university has 14 statistics classes scheduled for its Summer 2013 term. One class has space available for 30 students, eight classes have space for 60 students, one class has space for 70 students, and four classes have space for 100 students.

• What is the average class size assuming each class is filled to capacity?
• Space is available for 980 students. Suppose that each class is filled to capacity and select a statistics student at random. Let the random variable X equal the size of the student’s class. Define the PDF for X .
• Find the mean of X .
• Find the standard deviation of X .

In a raffle, there are 250 prizes of $5, 50 prizes of $25, and 10 prizes of $100. Assuming that 10,000 tickets are to be issued and sold, what is a fair price to charge to break even?

4.3 Binomial Distribution (Optional)

According to a recent article the average number of babies born with significant hearing loss (deafness) is approximately two per 1,000 babies in a healthy baby nursery. The number climbs to an average of 30 per 1,000 babies in an intensive care nursery.

Suppose that 1,000 babies from healthy baby nurseries were randomly surveyed. Find the probability that exactly two babies were born deaf.

Use the following information to answer the next four exercises : Recently, a nurse commented that when a patient calls the medical advice line claiming to have the flu, the chance that he or she truly has the flu (and not just a nasty cold) is only about 4 percent. Of the next 25 patients calling in claiming to have the flu, we are interested in how many actually have the flu.

Define the random variable and list its possible values.

State the distribution of X .

Find the probability that at least four of the 25 patients actually have the flu.

On average, for every 25 patients calling in, how many do you expect to have the flu?

People visiting video rental stores often rent more than one DVD at a time. The probability distribution for DVD rentals per customer at Video to Go is given Table 4.37 . There is a five-video limit per customer at this store, so nobody ever rents more than five DVDs.

• Find the probability that a customer rents at most two DVDs.

A school newspaper reporter decides to randomly survey 12 students to see if they will attend Tet (Vietnamese New Year) festivities this year. Based on past years, she knows that 18 percent of students attend Tet festivities. We are interested in the number of students who will attend the festivities.

• Give the distribution of X . X ~ _____ (_____,_____)
• How many of the 12 students do we expect to attend the festivities?
• Find the probability that at most four students will attend.
• Find the probability that more than two students will attend.

Use the following information to answer the next three exercises: The probability that a local hockey team will win any given game is 0.3694 based on a 13-year win history of 382 wins out of 1,034 games played (as of a certain date). An upcoming monthly schedule contains 12 games.

What is the expected number of wins for that upcoming month?

• 382 1043 382 1043

Let X = the number of games won in that upcoming month.

What is the probability that the team wins six games in that upcoming month?

What is the probability that the team wins at least five games in that upcoming month

A student takes a 10-question true-false quiz, but did not study and randomly guesses each answer. Find the probability that the student passes the quiz with a grade of at least 70 percent of the questions correct.

A student takes a 32-question multiple choice exam, but did not study and randomly guesses each answer. Each question has three possible choices for the answer. Find the probability that the student guesses more than 75 percent of the questions correctly.

Six different colored dice are rolled. Of interest is the number of dice that show a one.

• Give the distribution of X . X ~ _____(_____,_____)
• On average, how many dice would you expect to show a one?
• Find the probability that all six dice show a one.
• Is it more likely that three or that four dice will show a one? Use numbers to justify your answer numerically.

More than 96 percent of the very largest colleges and universities (more than 15,000 total enrollments) have some online offerings. Suppose you randomly pick 13 such institutions. We are interested in the number that offer distance learning courses.

• On average, how many schools would you expect to offer such courses?
• Find the probability that at most 10 offer such courses.
• Is it more likely that 12 or that 13 will offer such courses? Use numbers to justify your answer numerically and answer in a complete sentence.

Suppose that about 85 percent of graduating students attend their graduation. A group of 22 graduating students is randomly chosen.

• How many are expected to attend their graduation?
• Find the probability that 17 or 18 attend.
• Based on numerical values, would you be surprised if all 22 attended graduation? Justify your answer numerically.

At the Fencing Center, 60 percent of the fencers use the foil as their main weapon. We randomly survey 25 fencers at the Fencing Center. We are interested in the number of fencers who do not use the foil as their main weapon.

• How many are expected to not to use the foil as their main weapon?
• Find the probability that six do not use the foil as their main weapon.
• Based on numerical values, would you be surprised if all 25 did not use foil as their main weapon? Justify your answer numerically.

Approximately 8 percent of students at a local high school participate in after-school sports all four years of high school. A group of 60 seniors is randomly chosen. Of interest is the number who participated in after-school sports all four years of high school.

• How many seniors are expected to have participated in after-school sports all four years of high school?
• Based on numerical values, would you be surprised if none of the seniors participated in after-school sports all four years of high school? Justify your answer numerically.
• Based upon numerical values, is it more likely that four or that five of the seniors participated in after-school sports all four years of high school? Justify your answer numerically.

The chance of an IRS audit for a tax return reporting more than $25,000 in income is about 2 percent per year. We are interested in the expected number of audits a person with that income has in a 20-year period. Assume each year is independent.

• How many audits are expected in a 20-year period?
• Find the probability that a person is not audited at all.
• Find the probability that a person is audited more than twice.

It has been estimated that only about 30 percent of California residents have adequate earthquake supplies. Suppose you randomly survey 11 California residents. We are interested in the number who have adequate earthquake supplies.

• What is the probability that at least eight have adequate earthquake supplies?
• Is it more likely that none or that all of the residents surveyed will have adequate earthquake supplies? Why?
• How many residents do you expect will have adequate earthquake supplies?

There are two similar games played for Chinese New Year and Vietnamese New Year. In the Chinese version, fair dice with numbers 1, 2, 3, 4, 5, and 6 are used, along with a board with those numbers. In the Vietnamese version, fair dice with pictures of a gourd, fish, rooster, crab, crayfish, and deer are used. The board has those six objects on it, also. We will play with bets being $1. The player places a bet on a number or object. The house rolls three dice. If none of the dice show the number or object that was bet, the house keeps the $1 bet. If one of the dice shows the number or object bet (and the other two do not show it), the player gets back his or her $1 bet, plus $1 profit. If two of the dice show the number or object bet (and the third die does not show it), the player gets back his or her $1 bet, plus $2 profit. If all three dice show the number or object bet, the player gets back his or her $1 bet, plus $3 profit. Let X = number of matches and Y = profit per game.

• List the values that Y may take on. Then, construct one PDF table that includes both X and Y and their probabilities.
• Calculate the average expected matches over the long run of playing this game for the player.
• Calculate the average expected earnings over the long run of playing this game for the player.
• Determine who has the advantage, the player or the house.

According to the World Bank, only 9 percent of the population of Uganda had access to electricity as of 2009. Suppose we randomly sample 150 people in Uganda. Let X = the number of people who have access to electricity.

• What is the probability distribution for X ?
• Using the formulas, calculate the mean and standard deviation of X .
• Use your calculator to find the probability that 15 people in the sample have access to electricity.
• Find the probability that at most 10 people in the sample have access to electricity.
• Find the probability that more than 25 people in the sample have access to electricity.

The literacy rate for a nation measures the proportion of people age 15 and over who can read and write. The literacy rate in Afghanistan is 28.1 percent. Suppose you choose 15 people in Afghanistan at random. Let X = the number of people who are literate.

• Sketch a graph of the probability distribution of X .
• Using the formulas, calculate the (i) mean and (ii) standard deviation of X .
• Find the probability that more than five people in the sample are literate. Is it more likely that three people or four people are literate?

4.4 Geometric Distribution (Optional)

A consumer looking to buy a used red sports car will call dealerships until she finds a dealership that carries the car. She estimates the probability that any independent dealership will have the car will be 28 percent. We are interested in the number of dealerships she must call.

• On average, how many dealerships would we expect her to have to call until she finds one that has the car?
• Find the probability that she must call at most four dealerships.
• Find the probability that she must call three or four dealerships.

Suppose that the probability that an adult in America will watch the Super Bowl is 40 percent. Each person is considered independent. We are interested in the number of adults in America we must survey until we find one who will watch the Super Bowl.

• How many adults in America do you expect to survey until you find one who will watch the Super Bowl?
• Find the probability that you must ask seven people.
• Find the probability that you must ask three or four people.

It has been estimated that only about 30 percent of California residents have adequate earthquake supplies. Suppose we are interested in the number of California residents we must survey until we find a resident who does not have adequate earthquake supplies.

• What is the probability that we must survey just one or two residents until we find a California resident who does not have adequate earthquake supplies?
• What is the probability that we must survey at least three California residents until we find a California resident who does not have adequate earthquake supplies?
• How many California residents do you expect to need to survey until you find a California resident who does not have adequate earthquake supplies?
• How many California residents do you expect to need to survey until you find a California resident who does have adequate earthquake supplies?

In one of its spring catalogs, a retailer advertised footwear on 29 of its 192 catalog pages. Suppose we randomly survey 20 pages. We are interested in the number of pages that advertise footwear. Each page may be picked more than once.

• How many pages do you expect to advertise footwear on them?
• Is it probable that all 20 will advertise footwear on them? Why or why not?
• What is the probability that fewer than 10 will advertise footwear on them?
• Reminder: A page may be picked more than once. We are interested in the number of pages that we must randomly survey until we find one that has footwear advertised on it. Define the random variable X and give its distribution.
• What is the probability that you only need to survey at most three pages in order to find one that advertises footwear on it?
• How many pages do you expect to need to survey in order to find one that advertises footwear?

Suppose that you are performing the probability experiment of rolling one fair six-sided die. Let F be the event of rolling a four or a five. You are interested in how many times you need to roll the die to obtain the first four or five as the outcome.

• p = probability of success (event F occurs)
• q = probability of failure (event F does not occur)
• Write the description of the random variable X .
• What are the values that X can take on?
• Find the values of p and q .
• Find the probability that the first occurrence of event F (rolling a four or five) is on the second trial.

Ellen has music practice three days a week. She practices for all of the three days 85 percent of the time, two days 8 percent of the time, one day 4 percent of the time, and no days 3 percent of the time. One week is selected at random. What values does X take on?

Researchers investigate the prevalence of a particular infectious disease in countries around the world. According to their data, “Prevalence of this disease refers to the percentage of people ages 15 to 49 who are infected with it.” In South Africa, the prevalence of this disease is 17.3 percent. Let X = the number of people you test until you find a person infected with this disease.

• Sketch a graph of the distribution of the discrete random variable X .
• What is the probability that you must test 30 people to find one with this disease?
• What is the probability that you must ask 10 people?
• Find the (i) mean and (ii) standard deviation of the distribution of X .

According to a recent poll, 75 percent of millennials (people born between 1981 and 1995) have a profile on a social networking site. Let X = the number of millennials you ask until you find a person without a profile on a social networking site.

• Describe the distribution of X .
• Find the (i) mean and (ii) standard deviation of X .
• What is the probability that you must ask 10 people to find one person without a social networking site?
• What is the probability that you must ask 20 people to find one person without a social networking site?
• What is the probability that you must ask at most five people?

4.5 Hypergeometric Distribution (Optional)

A group of martial arts students is planning on participating in an upcoming demonstration. Six are students of tae kwon do, and seven are students of shotokan karate. Suppose that eight students are randomly picked to be in the first demonstration. We are interested in the number of shotokan karate students in that first demonstration.

• How many shotokan karate students do we expect to be in that first demonstration?

In one of its spring catalogs, a retailer advertised footwear on 29 of its 192 catalog pages. Suppose we randomly survey 20 pages. We are interested in the number of pages that advertise footwear. Each page may be picked at most once.

• Calculate the standard deviation.

Suppose that a technology task force is being formed to study technology awareness among instructors. Assume that 10 people will be randomly chosen to be on the committee from a group of 28 volunteers, 20 who are technically proficient and eight who are not. We are interested in the number on the committee who are not technically proficient.

• How many instructors do you expect on the committee who are not technically proficient?
• Find the probability that at least five on the committee are not technically proficient.
• Find the probability that at most three on the committee are not technically proficient.

Suppose that nine Massachusetts athletes are scheduled to appear at a charity benefit. The nine are randomly chosen from eight volunteers from the local basketball team and four volunteers from the local football team. We are interested in the number of football players picked.

• Are you choosing the nine athletes with or without replacement?

A bridge hand is defined as 13 cards selected at random and without replacement from a deck of 52 cards. In a standard deck of cards, there are 13 cards from each suit: hearts, spades, clubs, and diamonds. What is the probability of being dealt a hand that does not contain a heart?

• What is the group of interest?
• How many are in the group of interest?
• How many are in the other group?
• Let X = _________. What values does X take on?
• The probability question is P (_______).
• Find the probability in question.

4.6 Poisson Distribution (Optional)

The switchboard in a Minneapolis law office gets an average of 5.5 incoming phone calls during the noon hour on Mondays. Experience shows that the existing staff can handle up to six calls in an hour. Let X = the number of calls received at noon.

• Find the mean and standard deviation of X .
• What is the probability that the office receives at most six calls at noon on Monday?
• Find the probability that the law office receives six calls at noon. What does this mean to the law office staff who get, on average, 5.5 incoming phone calls at noon?
• What is the probability that the office receives more than eight calls at noon?

The maternity ward at a hospital in the Philippines is one of the busiest in the world with an average of 60 births per day. Let X = the number of births in an hour.

• What is the probability that the maternity ward will deliver three babies in one hour?
• What is the probability that the maternity ward will deliver at most three babies in one hour?
• What is the probability that the maternity ward will deliver more than five babies in one hour?

A manufacturer of decorative string lights knows that 3 percent of its bulbs are defective. Using both the binomial and Poisson distributions, find the probability that a string of 100 lights contains at most four defective bulbs.

The average number of children a Japanese woman has in her lifetime is 1.37. Suppose that one Japanese woman is randomly chosen.

• Find the probability that she has no children.
• Find the probability that she has fewer children than the Japanese average.
• Find the probability that she has more children than the Japanese average.

The average number of children a Spanish woman has in her lifetime is 1.47. Suppose that one Spanish woman is randomly chosen.

• Find the probability that she has fewer children than the Spanish average.
• Find the probability that she has more children than the Spanish average.

Fertile, female cats produce an average of three litters per year. Suppose that one fertile, female cat is randomly chosen. Answer the questions about the cat's probability of litters in one year.

• Give the distribution of X . X ~ _______
• Find the probability that she has no litters in one year.
• Find the probability that she has at least two litters in one year.
• Find the probability that she has exactly three litters in one year.

The chance of having an extra fortune in a fortune cookie is about 3 percent. Given a bag of 144 fortune cookies, we are interested in the number of cookies with an extra fortune. Two distributions may be used to solve this problem, but only use one distribution to solve the problem.

• How many cookies do we expect to have an extra fortune?
• Find the probability that none of the cookies have an extra fortune.
• Find the probability that more than three have an extra fortune.
• As n increases, what happens involving the probabilities using the two distributions? Explain in complete sentences.

According to the South Carolina Department of Mental Health website, for every 200 U.S. women, the average number who suffer from a particular disease is one. Out of a randomly chosen group of 600 U.S. women. Determine the following:

• How many are expected to suffer from this disease?
• Find the probability that no one suffers from this disease.
• Find the probability that more than four suffer from this disease.

The chance of an IRS audit for a tax return reporting more than $25,000 in income is about 2 percent per year. Suppose that 100 people with tax returns over $25,000 are randomly picked. We are interested in the number of people audited in one year. Use a Poisson distribution to anwer the following questions.

• How many are expected to be audited?
• Find the probability that no one was audited.
• Find the probability that at least three were audited.
• Based on numerical values, is it more likely that four or that five of the seniors participated in after-school sports all four years of high school? Justify your answer numerically.

On average, Pierre, an amateur chef, drops three pieces of eggshell into every two cake batters he makes. Suppose that you buy one of his cakes.

• On average, how many pieces of eggshell do you expect to be in the cake?
• What is the probability that there will not be any pieces of eggshell in the cake?
• Let’s say that you buy one of Pierre’s cakes each week for six weeks. What is the probability that there will not be any eggshell in any of the cakes?
• Based upon the average given for Pierre, is it possible for there to be seven pieces of shell in the cake? Why?

Use the following information to answer the next two exercises: The average number of times per week that Mrs. Plum’s cats wake her up at night because they want to play is 10. We are interested in the number of times her cats wake her up each week.

In words, what is the random variable X ?

• the number of times Mrs. Plum’s cats wake her up each week
• the number of times Mrs. Plum’s cats wake her up each hour
• the number of times Mrs. Plum’s cats wake her up each night
• the number of times Mrs. Plum’s cats wake her up

Find the probability that her cats will wake her up no more than five times next week.

4.7 Discrete Distribution (Playing Card Experiment)

Use a programmable calculator to simulate a binomial distribution.

• How would you use the randInt function to simulate the number of successes in five trials of an experiment with two outcomes, each of which has a .5 probability of occurring?
• Use the randInt function to simulate 10 observations of the random variable in Part A.
• Find the sample mean and sample standard deviation.
• Compare the sample mean and sample standard deviation to the theoretical mean and the theoretical standard deviation.

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Want to cite, share, or modify this book? This book uses the Creative Commons Attribution License and you must attribute Texas Education Agency (TEA). The original material is available at: https://www.texasgateway.org/book/tea-statistics . Changes were made to the original material, including updates to art, structure, and other content updates.

Access for free at https://openstax.org/books/statistics/pages/1-introduction

• Authors: Barbara Illowsky, Susan Dean
• Publisher/website: OpenStax
• Book title: Statistics
• Publication date: Mar 27, 2020
• Location: Houston, Texas
• Book URL: https://openstax.org/books/statistics/pages/1-introduction
• Section URL: https://openstax.org/books/statistics/pages/4-homework

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Indiana solar eclipse forecasts have changed as of April 4. Could there be clear skies?

UPDATED FORECAST: Click here for latest solar eclipse weather prediction

The weather forecast for the April 8 total solar eclipse in Indianapolis has slightly changed as the day draws near.

The National Weather Service in Indianapolis offers a 7-day forecast, and despite wintry mix of cold and snow we’ve seen lately, the weather during the eclipse could be mild. NWS's prediction center is now saying Indy might see clear skies.

Here’s what meteorologists are forecasting as of April 4.

What’s Indianapolis weather like for April 8?

Still four days away, the forecast is limited and may change as we progress through the week.

The NWS local meteorologists in Indy say there will be a 10% chance of showers for Monday, April 8. This is a slightly better outlook than yesterday’s forecast for Monday which called for a 20% chance.

Skies are predicted to be partly cloudy with a high near 71 degrees . This is warmer than previous forecasts but calls for more cloud cover.

Winds are expected to gust around 22 mph in the afternoon.

Everything eclipse: The total solar eclipse is just days away. Here's everything you need to know

NWS Weather Prediction forecast for the eclipse

The NWS Weather Prediction Center, based out of Maryland, shows greatly improved conditions for Indianapolis during the eclipse.

The center predicts is now forecasting no cloud cover over Indianapolis skies, a huge improvement from its last forecast of at least 50% cloud cover. Northern Indiana is still expected to see some clouds.

Clear skies have become more likely for Central Indiana.

Hazardous weather outlooks are still uncertain, but the center is predicting rain and thunderstorms near the path of totality in Indiana as well as Texas, Arkansas and Ohio.

What does historic weather data show for the eclipse?

IndyStar analyzed historic weather data earlier this year and found disappointing news when it comes to the state’s cloud cover on April 8.

The cloud cover data between 2000-2023 fails to mention the word "sunny" even once, with the best observation being "fair."

NWS defines a "fair" sky as having less than 3/8ths cloud cover. "Partly cloudy" means between 3/8ths and 5/8ths cloud cover. "Mostly cloudy" is when 6/8 to 7/8 of the sky is covered with opaque clouds. And "cloudy" means 7/8ths or more of the sky is obscured.

The breakdown of recent April 8 cloud-cover observations looks like this:

• Fair — 5 days
• Partly cloudy — 3 days
• Mostly cloudy — 6 days
• Cloudy — 10 days

Karl Schneider is an IndyStar environment reporter. You can reach him at [email protected]. Follow him on Twitter  @karlstartswithk

IndyStar's environmental reporting project is made possible through the generous support of the nonprofit Nina Mason Pulliam Charitable Trust.

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Another month of robust US job growth points to continued economic strength

FILE - Waitress Rachel Gurcik serves customers at the Gateway Diner in Westville, Pa. on Oct. 22, 2023. On Friday, April 5, 2024, the U.S. government issues its March jobs report. (Tom Gralish/The Philadelphia Inquirer via AP, File)

FILE - Construction workers work in Mount Prospect, Ill., Monday, Feb. 26, 2024. On Friday, April 5, 2024, the U.S. government issues its March jobs report. (AP Photo/Nam Y. Huh, File)

FILE - Veterinarian surgeon Dr. Daniel Spector, center, with members of the surgical team Lauren Reeves, right, and Allison Elkowitz examine Tiny, a pug, in the surgery prep room at the Schwarzman Animal Medical Center, Friday, March 8, 2024, in New York. On Friday, April 5, 2024, the U.S. government issues its March jobs report. (AP Photo/Mary Altaffer, File)

• Copy Link copied

WASHINGTON (AP) — America’s employers delivered another outpouring of jobs in March, adding a sizzling 303,000 workers to their payrolls and bolstering hopes that the economy can vanquish inflation without succumbing to a recession in the face of high interest rates.

Last month’s job growth was up from a revised 270,000 in February and was far above the 200,000 jobs that economists had forecast. By any measure, it amounted to a major burst of hiring, and it reflected the economy’s ability to withstand the pressure of high borrowing costs resulting from the Federal Reserve’s interest rate hikes . With the nation’s consumers continuing to spend, many employers have kept hiring to meet steady customer demand.

Friday’s report from the Labor Department also showed that the unemployment rate dipped from 3.9% to 3.8%. The jobless rate has now remained below 4% for 26 straight months, the longest such streak since the 1960s. The government also revised up its estimate of job growth in January and February by a combined 22,000.

Normally, a blockbuster bounty of new jobs would raise concerns that a vibrant labor market would force companies to sharply raise pay to attract and keep workers, thereby fanning inflation pressures. But the March jobs report showed that wage growth was mild last month, which might allay any such fears. Average hourly wages were up 4.1% from a year earlier, the smallest year-over-year increase since mid-2021. From February to March, though, hourly pay did rise 0.3% after increasing 0.2% the month before.

The economy is sure to weigh on Americans’ minds as the November presidential vote nears and they assess President Joe Biden’s re-election bid. Many people still feel squeezed by the inflation surge that erupted in the spring of 2021. Eleven rate hikes by the Fed have helped send inflation tumbling from its peak. But average prices are still about 18% higher than they were in February 2021 — a fact for which Biden might pay a political price.

In a statement Friday, though, Biden argued that the economy’s strong performance means that his policies are paying off.

“My plan is growing the economy from the middle out and the bottom up, investing in all Americans and giving the middle class a fair shot,” he said. “Inflation has come down significantly. We’ve come a long way, but I won’t stop fighting for hard-working families.”

The 303,000 jobs that the economy added in March were the largest gain since last May. And they boosted average monthly job growth so far this year to a vigorous 276,000, an improvement even on 2023’s robust average of 251,000.

The unemployment rate fell last month even though a sizable 469,000 people entered the labor force looking for work. That influx increased the proportion of Americans who either have a job or are looking for one from 62.5% in February to 62.7%. A bigger labor force tends to ease pressure on companies to significantly raise wages, thereby slowing inflation pressures.

Though most industries added jobs last month, hiring was mainly concentrated in three categories: Healthcare and private education, leisure and hospitality and government accounted for nearly 69% of the hiring. In addition, construction companies added a solid 39,000 jobs.

Four years after the pandemic curbed travel and forced shutdowns of restaurants, bars and entertainment venues, those industries have finally regained their pre-pandemic employment level, with a category that includes such businesses adding 49,000 jobs in March.

The Fed’s policymakers are tracking the state of the economy, the job market and inflation to determine when to begin cutting interest rates from their multi-decade highs. Rate cuts by the Fed would likely lead, over time, to lower borrowing rates across the economy.

The central bank’s policymakers started raising rates two years ago to try to tame inflation, which by mid-2022 was running at a four-decade high. Those rate hikes — 11 of them from March 2022 through July 2023 — helped drastically slow inflation. Consumer prices were up 3.2% in February from a year earlier, far below a peak of 9.1% in June 2022.

The much higher borrowing costs for individuals and companies that resulted from the Fed’s rate hikes were widely expected to trigger a recession, with waves of layoffs and a painful rise in unemployment. Yet to the surprise of just about everyone, the economy has kept growing steadily and employers have kept hiring at a healthy pace.

Some economists believe that a rise in productivity — the amount of output that workers produce per hour — made it easier for companies to hire, raise pay and post bigger profits without having to raise prices. In addition, an influx of immigrants into the job market is believed to have addressed labor shortages and slowed upward pressure on wage growth. This helped cool inflation even as the economy kept growing.

“This report is like the macroeconomist’s Holy Grail,’’ said Julia Pollak, chief economist at the online job marketplace ZipRecruiter. “It’s pointing toward noninflationary growth.”

Noting the strong job growth, influx of new workers, declining unemployment and slowing wage growth, Pollak said, “It suggests that the Fed can walk and chew gum at the same time, bringing down inflation without crippling the labor market.”

In the meantime, the Fed has signaled that it expects to cut rates three times this year. But it is awaiting more inflation data to gain further confidence that annual price increases are heading toward its 2% target. Some economists have begun to question whether the Fed will need to cut rates anytime soon in light of the consistently durable U.S. economy.

The still-strong demand for labor has meant that some employers are still struggling to fill vacancies. One of them is John Zmuda, president of Moseys Production Machinists in Anaheim, California, who said it’s still “extremely hard’’ to find workers.

Though he receives plenty of resumes, Zmuda said “it seems like most people are just wage-hunting” rather than seeking a long-term career.

Moseys, a family-owned company that supplies the defense, aerospace, healthcare industries, wants to add three or four workers to a staff of 27. Zmuda said he has raised wages 10% over the past year or so. But California’s high cost of living, especially for housing, puts off some potential recruits.

Like many manufacturers, Moseys depends heavily on robots. But for an employer, automation goes only so far.

“People bring to the table their minds and eyes,” Zmuda said. “Robots do not. People will think before they do something.’’

Likewise, in Duncan, Oklahoma, Southern Machine Works, which also supplies the aerospace and defense industries, needs four or five machinists.

“It’s really been a struggle to find anyone,’’ said Frank Burch, CEO of the third-generation family firm.

Attracting recruits to a rural town of 23,000 is difficult, especially when the oil-field-services giant Halliburton is nearby and seeking workers, too.

“We’re just hiring individuals that seem to have the mental capacity to learn the business, and then we’re teaching them through our in-house training program,” Burch said.

Employers, he suggested, will probably have to get used to tighter labor markets:

“When you look at the demographics of the country – the baby boom’s gone, the current generation just isn’t having children. I just don’t really see it changing in my lifetime.’’

AP Economics Writer Christopher Rugaber contributed to this report.

Advertisement

Map: 4.8-Magnitude Earthquake Strikes New Jersey

By William B. Davis ,  Madison Dong ,  Judson Jones ,  John Keefe ,  Bea Malsky and Lazaro Gamio

Shake intensity

A light, 4.8-magnitude earthquake struck in New Jersey on Friday, according to the United States Geological Survey. The quake was felt across the New York City metropolitan area, and from Philadelphia to Boston.

The temblor happened at 10:23 a.m. Eastern about 4 miles north of Whitehouse Station, N.J., data from the agency shows.

As seismologists review available data, they may revise the earthquake's reported magnitude. Additional information collected about the earthquake may also prompt U.S.G.S. scientists to update the shake-severity map.

Aftershocks in the region

At 5:59 p.m. Eastern on Friday, a light aftershock with a magnitude of 3.8 struck near Gladstone, New Jersey, according to U.S.G.S. (The agency initially gave the quake a preliminary magnitude of 4.0.)

An aftershock is usually a smaller earthquake that follows a larger one in the same general area. Aftershocks are typically minor adjustments along the portion of a fault that slipped at the time of the initial earthquake.

Quakes and aftershocks within 100 miles

Aftershocks can occur days, weeks or even years after the first earthquake. These events can be of equal or larger magnitude to the initial earthquake, and they can continue to affect already damaged locations.

How this quake compares

The U.S.G.S. has logged 188 earthquakes with a magnitude of 2.5 or greater within a 250-mile radius of New York City since 1957. In that timeframe, only seven have had a magnitude at or above 4.5. Today’s quake had the third-highest magnitude in the available data.

Today’s earthquake

Magnitude 4.8

250-mile radius

from New York City

Source: U. S.G.S.

By Lazaro Gamio

Source: United States Geological Survey | Notes: Shaking categories are based on the Modified Mercalli Intensity scale. When aftershock data is available, the corresponding maps and charts include earthquakes within 100 miles and seven days of the initial quake. All times above are Eastern. Shake data is as of Friday, April 5 at 10:44 a.m. Eastern. Aftershocks data is as of Saturday, April 6 at 10:53 p.m. Eastern.

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Announcements

• Fri 29 April 2022
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• Wed 27 April 2022
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• HW10 due tomorrow, 4/14; submit by tonight for 5 bonus points.
• Project 2 OH Party this Friday, 1-5pm at SOCS 581!
• We're starting to release staff-created Tutoring Worksheet walkthrough videos .
• Check out the Data Science Faculty Advising events this week!
• Mon 11 April 2022
• Lab 9 released today & due Friday, 4/15 @ 5pm.
• Check out the Data Science Faculty Advising events next week!
• Fri 08 April 2022
• Project 2 OH party today!
• Project 2 checkpoint due tonight to the Project 2 Checkpoint assignment on Gradescope.
• HW10 will released after lecture today.
• Wed 06 April 2022
• Project 2 work session in section this week; no lab notebook released/due!
• Lab 7 regrades due tonight.
• Project 2 checkpoint due this Friday.
• Happy hump day :)
• Mon 04 April 2022
• Professor Swupnil's OH today (3-4pm) are cancelled this week, and will resume next week.
• Lab 7 regrades due this Wednesday
• Start coming to lecture, here's why !
• Happy Monday!
• Fri 01 April 2022
• Doggowork 9 released today after lecture.
• Dogect 2 released today, with checkpoint & final submissions due 4/8 and 4/15, respectively.
• Labbo 5 due @ 5pm to Gradescope.
• Check out our staff-created Confidence Interval Guide .
• Wed 30 March 2022
• Homework 7 regrade request are due by tonight.
• Lab 5 is due Friday @ 5pm.
• Fill out your GSI's Project Partner Matching Form if you haven't already!
• Mon 28 March 2022
• Lab 8 will be released tonight
• Homework 7 Regrades Due Wednesday
• Sign ups for Round 2 of tutoring sections currently out!
• Hope you had a great Spring Break!
• Fri 18 March 2022
• HW8 will be released after lecture today.
• Sign ups for Round 2 of tutoring were announced on Ed #1540 !
• Midterm regrades are due to Gradescope by tonight @ 11:59pm, no exceptions!
• Please make sure to read Ed #1508 for guidelines on submitting a valid regrade request: "Please check the solutions and common mistakes doc, and you have to consult your lab TA or attend OH to discuss why you think you deserve a regrade first."
• Have a fun and safe Spring Break :)
• Wed 16 March 2022
• Sign ups for Round 2 of tutoring sections will be released after lecture today!
• Lab 6, HW6, and Project 1 regrades are due tomorrow night (3/17) @ 11:59pm.
• Midterm regrades are due to Gradescope by this Friday @ 11:59pm, no exceptions!
• Check out our staff-created walkthrough videos for each midterm question.
• We've released class & individual performance reports; we strongly encourage you to read it as it may give you an idea of where you stand in the class based on your grades so far!
• T-3 days 'till Spring Break :)
• Mon 14 March 2022
• Lab 7 will be released tonight @ 10pm and due Friday @ 5pm.
• Sign ups for Round 2 of tutoring sections will be released after lecture this Wednesday, 4/16.
• Be on the lookout for more info about the midterm on Ed this afternoon :)
• T-5 days 'till Spring Break!
• Fri 11 March 2022
• Midterm is tonight, 7-9pm (regular); please arrive at your assigned room by 7pm.
• Read over the Midterm Logistics post for both in-person and online exam logistics.
• Look over the Midterm Reference Sheet and the In-Person Seating and Zoom Rooms post.
• Good luck on your midterm, you'll do great! Data 8 course staff is super proud of you :)
• Wed 09 March 2022
• Submit HW7 by tonight for 5 bonus points, otherwise submit by tomorrow, 3/10.
• Lab 5 and HW5 regrades are due tonight.
• Read over the Midterm Prep Post and Midterm Logistics post.
• Attend our GSI-led Midterm Review Sessions this week, or watch the recordings afterwards!
• Check out the Python Reference Sheet .
• Good luck studying, you got this! :)
• Mon 07 March 2022
• Lab 5 and HW5 regrades are due on Wednesday.
• Read over the Midterm Prep Post .
• We've posted more on the upcoming changes to the mask mandate .
• Fri 04 March 2022
• Lab 6 is due @ 5pm.
• Check out the Sampling Methods Guide on Ed #1158 !
• Request an alternate or online midterm by today at 12pm.
• Wed 02 March 2022
• Submit HW6 early today for 5 bonus points.
• HW4 regrades are due tonight!
• HW7 will be released early today, around 3pm.
• This Friday, 3/4, is the last day to request an alternate or online midterm.
• Mon 28 February 2022
• Start on HW6 early, and head to OH this week for any questions!
• Lab 5 & HW5 solutions will be released today.
• Lab 6 will be released tonight.
• Q: How many months have 28 days? A: All of them!
• Fri 25 February 2022
• Submit Project 1 to the Project 1 Autograder portal by tonight!
• Lab 5 is due by 5pm to Gradescope.
• HW6 will be released today after lecture.
• HW4 grades will be released later today.
• Haaaave an great weekend :)
• Wed 23 February 2022
• Submit Homework 5 by tonight for 5 bonus points.
• Lab 4 and HW3 regade requests are due tonight.
• Submit Project 1 to the Project 1 Autograder portal by Thursday night for 5 bonus points. Remember to add your partner to the submission on Gradescope!
• Happy hump day!
• Fri 18 February 2022
• Project 1 Checkpoint is due tonight (02/18) at 11:59 pm; make sure to submit to the Project 1 Checkpoint portal on Gradescope, not to the Project 1 Autograder portal!
• Homework 5 will be released after lecture today.
• Tutoring sections on next Monday will be rescheduled to online sections later in the week; more info to come on Ed!
• No lecture on Monday (02/21) for President's Day; have a fantastic weekend :)
• Wed 16 February 2022
• Submit HW4 by tonight for 5 bonus points, otherwise submit by Thursday at 11:59pm.
• HW2 and Lab 3 regrades are due to Gradescope or your GSI by tonight.
• If you haven't already, bookmark the Student Materials Google Drive to access lab worksheet and tutoring worksheet solutions, as well as other helpful materials!
• Mon 14 February 2022
• No lab notebook released or due this week; work on the project during section!
• HW3 and Lab 4 solutions will be released later today.
• HW2 and Lab 3 regrades are due by Wednesday, 2/16.
• If you are in a self-service lab and would like to find a project partner, check out this Partner Finding post on Ed.
• Happy Valentine's Day!
• Fri 11 February 2022
• Project 1 will be released today after lecture, with checkpoint and final submission due dates on 2/18 and 2/25, respectively.
• HW4 will be released today after lecture and is due next Thursday.
• HW2 and Lab 3 grades will be released tonight. Regrades are due by Wednesday, 2/16.
• As a note, we will no longer be accepting lab swaps since the add/drop deadline has passed.
• Happy Super Bowl weekend; go Rams & Bengals!
• Wed 09 February 2022
• Submit HW3 by tonight for 5 bonus points.
• HW1 and Lab 2 regrade requests are due tonight.
• Be on the lookout for your GSI's Project 1 Partner Matching Form this week!
• Check out the Arrays Primer Guide on Ed!
• Mon 07 February 2022
• Lab 4 will be released tonight!
• HW2 and Lab 3 solutions will be released later today.
• HW1 and Lab 2 regrade requests are due by Wednesday.
• Be on the lookout for your GSI's Project 1 Partner Matching Form this week.
• Please read Ed #389 post about midterm/final exam conflicts.
• Welcome to Week 4 :)
• Fri 04 February 2022
• HW3 will be released today!
• Lab 3 is due to Gradescope today by 5pm.
• HW1 and Lab 2 grades will be released today; regrade request are due by Wednesday, 2/9.
• Have a data gr8 weekend :D
• Wed 02 February 2022
• Lab 1 regrades are due tonight!
• HW 2 is due tomorrow; submit by tonight for 5 bonus points.
• Mon 31 January 2022
• HW 1 and Lab 2 solutions will be released today.
• Lab 1 regrades are due by this Wednesday, 2/2.
• HW 2 is due this Thursday; submit by Wednesday for 5 bonus points.
• Tutoring sections start this week; there are still a few spots left (Ed #210 )!
• Be on the lookout for an Ed post about midterm/final exam conflicts.
• Stay safe, and welcome back to in-person instruction :)
• Fri 28 January 2022
• Submit Wednesday (2/2) for a bit of extra credit
• You can still join via Zoom: link
• To attend lecture in person on Monday: Please fill out this form by 8pm Sunday, (1/30)
• There will still be videos posted here
• Have a wonderful weekend!
• Wed 26 January 2022
• Homework 1 is due this Thursday, 1/27 @ 11:59pm; turn it in by 11:59pm on Wednesday for 5 bonus points.
• Office hours start online this week! Check out the office hours calendar for dates & times.
• Sign up for tutoring on Ed #210 .
• Check out our Gradescope Submission Troubleshooting Guide .
• Mon 24 January 2022
• Lab 2 will be released tonight and due by Friday @ 5pm.
• Tutoring sign-ups will be released today at 12pm on Ed!
• Friendly reminder to make sure you are submitting the entire zip file to Gradescope, and not unzipping the folder beforehand!
• Fri 21 January 2022
• Lab 1 is due today at 5pm PT.
• Homework 1 will be released after lecture and is due next Thursday, 1/27 at 11:59pm PT. Turn it in by Wednesday, 1/26 at 11:59pm PT for 5 bonus points.
• Check out our staff-created Data 8 Resources Walkthrough Videos to learn how to navigate the website, Datahub, Zoom, etc.
• Have a great weekend :)
• Wed 19 January 2022
• Welcome to Data 8!
• Make sure you are enrolled in the Data 8 Spring 2022 Ed page ! Check Ed daily for all course announcements.
• Watch our staff-created Data 8 Resources Walkthrough Videos to learn how to navigate the website, Datahub, Zoom, etc.
• Lab sections start this week. Check sections.data8.org for your assigned section, and Ed post #27 for the first two week's Zoom links.
• Lab 1 is due to Gradescope this Friday at 5pm PT.
• Sun 09 January 2022
• This website is still under development; information is subject to change.

Instructors : John DeNero and Swupnil Sahai

Lecture : MWF 10am-11am