critique research abstract

What this handout is about

This handout provides definitions and examples of the two main types of abstracts: descriptive and informative. It also provides guidelines for constructing an abstract and general tips for you to keep in mind when drafting. Finally, it includes a few examples of abstracts broken down into their component parts.

What is an abstract?

An abstract is a self-contained, short, and powerful statement that describes a larger work. Components vary according to discipline. An abstract of a social science or scientific work may contain the scope, purpose, results, and contents of the work. An abstract of a humanities work may contain the thesis, background, and conclusion of the larger work. An abstract is not a review, nor does it evaluate the work being abstracted. While it contains key words found in the larger work, the abstract is an original document rather than an excerpted passage.

Why write an abstract?

You may write an abstract for various reasons. The two most important are selection and indexing. Abstracts allow readers who may be interested in a longer work to quickly decide whether it is worth their time to read it. Also, many online databases use abstracts to index larger works. Therefore, abstracts should contain keywords and phrases that allow for easy searching.

Say you are beginning a research project on how Brazilian newspapers helped Brazil’s ultra-liberal president Luiz Ignácio da Silva wrest power from the traditional, conservative power base. A good first place to start your research is to search Dissertation Abstracts International for all dissertations that deal with the interaction between newspapers and politics. “Newspapers and politics” returned 569 hits. A more selective search of “newspapers and Brazil” returned 22 hits. That is still a fair number of dissertations. Titles can sometimes help winnow the field, but many titles are not very descriptive. For example, one dissertation is titled “Rhetoric and Riot in Rio de Janeiro.” It is unclear from the title what this dissertation has to do with newspapers in Brazil. One option would be to download or order the entire dissertation on the chance that it might speak specifically to the topic. A better option is to read the abstract. In this case, the abstract reveals the main focus of the dissertation:

This dissertation examines the role of newspaper editors in the political turmoil and strife that characterized late First Empire Rio de Janeiro (1827-1831). Newspaper editors and their journals helped change the political culture of late First Empire Rio de Janeiro by involving the people in the discussion of state. This change in political culture is apparent in Emperor Pedro I’s gradual loss of control over the mechanisms of power. As the newspapers became more numerous and powerful, the Emperor lost his legitimacy in the eyes of the people. To explore the role of the newspapers in the political events of the late First Empire, this dissertation analyzes all available newspapers published in Rio de Janeiro from 1827 to 1831. Newspapers and their editors were leading forces in the effort to remove power from the hands of the ruling elite and place it under the control of the people. In the process, newspapers helped change how politics operated in the constitutional monarchy of Brazil.

From this abstract you now know that although the dissertation has nothing to do with modern Brazilian politics, it does cover the role of newspapers in changing traditional mechanisms of power. After reading the abstract, you can make an informed judgment about whether the dissertation would be worthwhile to read.

Besides selection, the other main purpose of the abstract is for indexing. Most article databases in the online catalog of the library enable you to search abstracts. This allows for quick retrieval by users and limits the extraneous items recalled by a “full-text” search. However, for an abstract to be useful in an online retrieval system, it must incorporate the key terms that a potential researcher would use to search. For example, if you search Dissertation Abstracts International using the keywords “France” “revolution” and “politics,” the search engine would search through all the abstracts in the database that included those three words. Without an abstract, the search engine would be forced to search titles, which, as we have seen, may not be fruitful, or else search the full text. It’s likely that a lot more than 60 dissertations have been written with those three words somewhere in the body of the entire work. By incorporating keywords into the abstract, the author emphasizes the central topics of the work and gives prospective readers enough information to make an informed judgment about the applicability of the work.

When do people write abstracts?

• when submitting articles to journals, especially online journals
• when applying for research grants
• when writing a book proposal
• when completing the Ph.D. dissertation or M.A. thesis
• when writing a proposal for a conference paper
• when writing a proposal for a book chapter

Most often, the author of the entire work (or prospective work) writes the abstract. However, there are professional abstracting services that hire writers to draft abstracts of other people’s work. In a work with multiple authors, the first author usually writes the abstract. Undergraduates are sometimes asked to draft abstracts of books/articles for classmates who have not read the larger work.

Types of abstracts

There are two types of abstracts: descriptive and informative. They have different aims, so as a consequence they have different components and styles. There is also a third type called critical, but it is rarely used. If you want to find out more about writing a critique or a review of a work, see the UNC Writing Center handout on writing a literature review . If you are unsure which type of abstract you should write, ask your instructor (if the abstract is for a class) or read other abstracts in your field or in the journal where you are submitting your article.

Descriptive abstracts

A descriptive abstract indicates the type of information found in the work. It makes no judgments about the work, nor does it provide results or conclusions of the research. It does incorporate key words found in the text and may include the purpose, methods, and scope of the research. Essentially, the descriptive abstract describes the work being abstracted. Some people consider it an outline of the work, rather than a summary. Descriptive abstracts are usually very short—100 words or less.

Informative abstracts

The majority of abstracts are informative. While they still do not critique or evaluate a work, they do more than describe it. A good informative abstract acts as a surrogate for the work itself. That is, the writer presents and explains all the main arguments and the important results and evidence in the complete article/paper/book. An informative abstract includes the information that can be found in a descriptive abstract (purpose, methods, scope) but also includes the results and conclusions of the research and the recommendations of the author. The length varies according to discipline, but an informative abstract is rarely more than 10% of the length of the entire work. In the case of a longer work, it may be much less.

Here are examples of a descriptive and an informative abstract of this handout on abstracts . Descriptive abstract:

The two most common abstract types—descriptive and informative—are described and examples of each are provided.

Informative abstract:

Abstracts present the essential elements of a longer work in a short and powerful statement. The purpose of an abstract is to provide prospective readers the opportunity to judge the relevance of the longer work to their projects. Abstracts also include the key terms found in the longer work and the purpose and methods of the research. Authors abstract various longer works, including book proposals, dissertations, and online journal articles. There are two main types of abstracts: descriptive and informative. A descriptive abstract briefly describes the longer work, while an informative abstract presents all the main arguments and important results. This handout provides examples of various types of abstracts and instructions on how to construct one.

Which type should I use?

Your best bet in this case is to ask your instructor or refer to the instructions provided by the publisher. You can also make a guess based on the length allowed; i.e., 100-120 words = descriptive; 250+ words = informative.

How do I write an abstract?

The format of your abstract will depend on the work being abstracted. An abstract of a scientific research paper will contain elements not found in an abstract of a literature article, and vice versa. However, all abstracts share several mandatory components, and there are also some optional parts that you can decide to include or not. When preparing to draft your abstract, keep the following key process elements in mind:

• Reason for writing: What is the importance of the research? Why would a reader be interested in the larger work?
• Problem: What problem does this work attempt to solve? What is the scope of the project? What is the main argument/thesis/claim?
• Methodology: An abstract of a scientific work may include specific models or approaches used in the larger study. Other abstracts may describe the types of evidence used in the research.
• Results: Again, an abstract of a scientific work may include specific data that indicates the results of the project. Other abstracts may discuss the findings in a more general way.
• Implications: What changes should be implemented as a result of the findings of the work? How does this work add to the body of knowledge on the topic?

(This list of elements is adapted with permission from Philip Koopman, “How to Write an Abstract.” )

All abstracts include:

• A full citation of the source, preceding the abstract.
• The most important information first.
• The same type and style of language found in the original, including technical language.
• Key words and phrases that quickly identify the content and focus of the work.
• Clear, concise, and powerful language.

Abstracts may include:

• The thesis of the work, usually in the first sentence.
• Background information that places the work in the larger body of literature.
• The same chronological structure as the original work.

How not to write an abstract:

• Do not refer extensively to other works.
• Do not add information not contained in the original work.
• Do not define terms.

If you are abstracting your own writing

When abstracting your own work, it may be difficult to condense a piece of writing that you have agonized over for weeks (or months, or even years) into a 250-word statement. There are some tricks that you could use to make it easier, however.

Reverse outlining:

This technique is commonly used when you are having trouble organizing your own writing. The process involves writing down the main idea of each paragraph on a separate piece of paper– see our short video . For the purposes of writing an abstract, try grouping the main ideas of each section of the paper into a single sentence. Practice grouping ideas using webbing or color coding .

For a scientific paper, you may have sections titled Purpose, Methods, Results, and Discussion. Each one of these sections will be longer than one paragraph, but each is grouped around a central idea. Use reverse outlining to discover the central idea in each section and then distill these ideas into one statement.

Cut and paste:

To create a first draft of an abstract of your own work, you can read through the entire paper and cut and paste sentences that capture key passages. This technique is useful for social science research with findings that cannot be encapsulated by neat numbers or concrete results. A well-written humanities draft will have a clear and direct thesis statement and informative topic sentences for paragraphs or sections. Isolate these sentences in a separate document and work on revising them into a unified paragraph.

If you are abstracting someone else’s writing

When abstracting something you have not written, you cannot summarize key ideas just by cutting and pasting. Instead, you must determine what a prospective reader would want to know about the work. There are a few techniques that will help you in this process:

Identify key terms:

Search through the entire document for key terms that identify the purpose, scope, and methods of the work. Pay close attention to the Introduction (or Purpose) and the Conclusion (or Discussion). These sections should contain all the main ideas and key terms in the paper. When writing the abstract, be sure to incorporate the key terms.

Highlight key phrases and sentences:

Instead of cutting and pasting the actual words, try highlighting sentences or phrases that appear to be central to the work. Then, in a separate document, rewrite the sentences and phrases in your own words.

Don’t look back:

After reading the entire work, put it aside and write a paragraph about the work without referring to it. In the first draft, you may not remember all the key terms or the results, but you will remember what the main point of the work was. Remember not to include any information you did not get from the work being abstracted.

Revise, revise, revise

No matter what type of abstract you are writing, or whether you are abstracting your own work or someone else’s, the most important step in writing an abstract is to revise early and often. When revising, delete all extraneous words and incorporate meaningful and powerful words. The idea is to be as clear and complete as possible in the shortest possible amount of space. The Word Count feature of Microsoft Word can help you keep track of how long your abstract is and help you hit your target length.

Example 1: Humanities abstract

Kenneth Tait Andrews, “‘Freedom is a constant struggle’: The dynamics and consequences of the Mississippi Civil Rights Movement, 1960-1984” Ph.D. State University of New York at Stony Brook, 1997 DAI-A 59/02, p. 620, Aug 1998

This dissertation examines the impacts of social movements through a multi-layered study of the Mississippi Civil Rights Movement from its peak in the early 1960s through the early 1980s. By examining this historically important case, I clarify the process by which movements transform social structures and the constraints movements face when they try to do so. The time period studied includes the expansion of voting rights and gains in black political power, the desegregation of public schools and the emergence of white-flight academies, and the rise and fall of federal anti-poverty programs. I use two major research strategies: (1) a quantitative analysis of county-level data and (2) three case studies. Data have been collected from archives, interviews, newspapers, and published reports. This dissertation challenges the argument that movements are inconsequential. Some view federal agencies, courts, political parties, or economic elites as the agents driving institutional change, but typically these groups acted in response to the leverage brought to bear by the civil rights movement. The Mississippi movement attempted to forge independent structures for sustaining challenges to local inequities and injustices. By propelling change in an array of local institutions, movement infrastructures had an enduring legacy in Mississippi.

Now let’s break down this abstract into its component parts to see how the author has distilled his entire dissertation into a ~200 word abstract.

What the dissertation does This dissertation examines the impacts of social movements through a multi-layered study of the Mississippi Civil Rights Movement from its peak in the early 1960s through the early 1980s. By examining this historically important case, I clarify the process by which movements transform social structures and the constraints movements face when they try to do so.

How the dissertation does it The time period studied in this dissertation includes the expansion of voting rights and gains in black political power, the desegregation of public schools and the emergence of white-flight academies, and the rise and fall of federal anti-poverty programs. I use two major research strategies: (1) a quantitative analysis of county-level data and (2) three case studies.

What materials are used Data have been collected from archives, interviews, newspapers, and published reports.

Conclusion This dissertation challenges the argument that movements are inconsequential. Some view federal agencies, courts, political parties, or economic elites as the agents driving institutional change, but typically these groups acted in response to movement demands and the leverage brought to bear by the civil rights movement. The Mississippi movement attempted to forge independent structures for sustaining challenges to local inequities and injustices. By propelling change in an array of local institutions, movement infrastructures had an enduring legacy in Mississippi.

Keywords social movements Civil Rights Movement Mississippi voting rights desegregation

Example 2: Science Abstract

Luis Lehner, “Gravitational radiation from black hole spacetimes” Ph.D. University of Pittsburgh, 1998 DAI-B 59/06, p. 2797, Dec 1998

The problem of detecting gravitational radiation is receiving considerable attention with the construction of new detectors in the United States, Europe, and Japan. The theoretical modeling of the wave forms that would be produced in particular systems will expedite the search for and analysis of detected signals. The characteristic formulation of GR is implemented to obtain an algorithm capable of evolving black holes in 3D asymptotically flat spacetimes. Using compactification techniques, future null infinity is included in the evolved region, which enables the unambiguous calculation of the radiation produced by some compact source. A module to calculate the waveforms is constructed and included in the evolution algorithm. This code is shown to be second-order convergent and to handle highly non-linear spacetimes. In particular, we have shown that the code can handle spacetimes whose radiation is equivalent to a galaxy converting its whole mass into gravitational radiation in one second. We further use the characteristic formulation to treat the region close to the singularity in black hole spacetimes. The code carefully excises a region surrounding the singularity and accurately evolves generic black hole spacetimes with apparently unlimited stability.

This science abstract covers much of the same ground as the humanities one, but it asks slightly different questions.

Why do this study The problem of detecting gravitational radiation is receiving considerable attention with the construction of new detectors in the United States, Europe, and Japan. The theoretical modeling of the wave forms that would be produced in particular systems will expedite the search and analysis of the detected signals.

What the study does The characteristic formulation of GR is implemented to obtain an algorithm capable of evolving black holes in 3D asymptotically flat spacetimes. Using compactification techniques, future null infinity is included in the evolved region, which enables the unambiguous calculation of the radiation produced by some compact source. A module to calculate the waveforms is constructed and included in the evolution algorithm.

Results This code is shown to be second-order convergent and to handle highly non-linear spacetimes. In particular, we have shown that the code can handle spacetimes whose radiation is equivalent to a galaxy converting its whole mass into gravitational radiation in one second. We further use the characteristic formulation to treat the region close to the singularity in black hole spacetimes. The code carefully excises a region surrounding the singularity and accurately evolves generic black hole spacetimes with apparently unlimited stability.

Keywords gravitational radiation (GR) spacetimes black holes

Works consulted

We consulted these works while writing this handout. This is not a comprehensive list of resources on the handout’s topic, and we encourage you to do your own research to find additional publications. Please do not use this list as a model for the format of your own reference list, as it may not match the citation style you are using. For guidance on formatting citations, please see the UNC Libraries citation tutorial . We revise these tips periodically and welcome feedback.

Belcher, Wendy Laura. 2009. Writing Your Journal Article in Twelve Weeks: A Guide to Academic Publishing Success. Thousand Oaks, CA: Sage Press.

Koopman, Philip. 1997. “How to Write an Abstract.” Carnegie Mellon University. October 1997. http://users.ece.cmu.edu/~koopman/essays/abstract.html .

Lancaster, F.W. 2003. Indexing And Abstracting in Theory and Practice , 3rd ed. London: Facet Publishing.

You may reproduce it for non-commercial use if you use the entire handout and attribute the source: The Writing Center, University of North Carolina at Chapel Hill

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• Queen's University Library
• Research Guides

How to Critique an Article (Psychology)

• Introduction

Participants

• Is the sample size adequate to find the effect? Are power analyses mentioned?
• Are there equal numbers of males and females?
• Are there a range of socioeconomic strata and ethnicities?
• For this class, is the diagnosis confirmed?
• Where were the participants obtained from, and are they a biased sample?
• If it is an experimental design, was true random assignment done (random number generator)?
• Are the measures widely used in the field?
• Are the measures reliable and valid?
• Are they appropriate for the group or age being studied (i.e. not too difficult or too easy)?
• Are all the measures explained adequately?
• Do the measures seem to have face validity -- that is, do they measure what the authors say the variable of interest is in an adequate fashion?

• Last Updated: Nov 5, 2021 9:46 AM
• Subjects: Psychology

A guide for critique of research articles

Following is the list of criteria to evaluate (critique) a research article. Please note that you should first summarize the paper and then evaluate different parts of it.

Most of the evaluation section should be devoted to evaluation of internal validity of the conclusions. Please add at the end a section entitled ''changes in the design/procedures if I want to replicate this study." Attach a copy of the original article to your paper.

Click here to see a an example (this is how you start) of a research critique.

Click here to see the original article.

The following list is a guide for you to organize your evaluation. It is recommended to organize your evaluation in this order. This is a long list of questions. You don’t have to address all questions. However, you should address highlighted questions . Some questions may not be relevant to your article.

Introduction

1.     Is there a statement of the problem?

2.     Is the problem “researchable”? That is, can it be investigated through the collection and analysis of data?

3.     Is background information on the problem presented?

4.     Is the educational significance of the problem discussed?

5.     Does the problem statement indicate the variables of interest and the specific relationship between those variables which are investigated? When necessary, are variables directly or operationally defined?

Review of Related Literature

1.     Is the review comprehensive?

2.     Are all cited references relevant to the problem under investigation?

3.     Are most of the sources primary, i.e., are there only a few or no secondary sources?

4.     Have the references been critically analyzed and the results of various studies compared and contrasted, i.e., is the review more than a series of abstracts or annotations?

5.     Does the review conclude with a brief summary of the literature and its implications for the problem investigated?

6.     Do the implications discussed form an empirical or theoretical rationale for the hypotheses which follow?

1.     Are specific questions to be answered listed or specific hypotheses to be tested stated?

2.     Does each hypothesis state an expected relationship or difference?

3.     If necessary, are variables directly or operationally defined?

4.     Is each hypothesis testable?

Method          Subjects

1.     Are the size and major characteristics of the population studied described?

2.     If a sample was selected, is the method of selecting the sample clearly described?

3.      Is the method of sample selection described one that is likely to result in a representative, unbiased sample?

4.     Did the researcher avoid the use of volunteers?

5.     Are the size and major characteristics of the sample described?

6.     Does the sample size meet the suggested guideline for minimum sample size appropriate for the method of research represented?      

Instruments

1.     Is the rationale given for the selection of the instruments (or measurements) used?

2.     Is each instrument described in terms of purpose and content?

3.     Are the instruments appropriate for measuring the intended variables?

4.     Is evidence presented that indicates that each instrument is appropriate for the sample under study?

5.     Is instrument validity discussed and coefficients given if appropriate?

6.     Is reliability discussed in terms of type and size of reliability coefficients?

7.     If appropriate, are subtest reliabilities given?

8.     If an instrument was developed specifically for the study, are the procedures involved in its development and validation described?

9.     If an instrument was developed specifically for the study, are administration, scoring or tabulating, and interpretation procedures fully described?

Design and Procedure

1.     Is the design appropriate for answering the questions or testing the hypotheses of the   study?

2.     Are the procedures described in sufficient detail to permit them to be replicated by another researcher?

3.     If a pilot study was conducted, are its execution and results described as well as its impact on the subsequent study?

4.     Are the control procedures described?

5.     Did the researcher discuss or account for any potentially confounding variables that he or she was unable to control for?

1.     Are appropriate descriptive or inferential statistics presented?

2.     Was the probability level, α, at which the results of the tests of significance were evaluated,

       specified in advance of the data analyses?

3.     If parametric tests were used, is there evidence that the researcher avoided violating the

       required assumptions for parametric tests?

4.     Are the tests of significance described appropriate, given the hypotheses and design of the

       study?

5.     Was every hypothesis tested?

6.     Are the tests of significance interpreted using the appropriate degrees of freedom?

7.     Are the results clearly presented?

8.     Are the tables and figures (if any) well organized and easy to understand?

9.     Are the data in each table and figure described in the text?

Discussion (Conclusions and Recommendation)

1.     Is each result discussed in terms of the original hypothesis to which it relates?

2.     Is each result discussed in terms of its agreement or disagreement with previous results

        obtained by other researchers in other studies?

3.     Are generalizations consistent with the results?

4.     Are the possible effects of uncontrolled variables on the results discussed?

5.     Are theoretical and practical implications of the findings discussed?

6.     Are recommendations for future action made?

7.     Are the suggestions for future action based on practical significance or on statistical

       significance only, i.e., has the author avoided confusing practical and statistical

       significance?

8.     Are recommendations for future research made?

Additional general questions to be answered in your critique.

1. What is (are) the research question(s) (or hypothesis)?

2. Describe the sample used in this study.

3. Describe the reliability and validity of all the instruments used.

4. What type of research is this?  Explain.

5. How was the data analyzed?

6. What is (are) the major finding(s)?

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• How to Write an Abstract | Steps & Examples

How to Write an Abstract | Steps & Examples

Published on February 28, 2019 by Shona McCombes . Revised on July 18, 2023 by Eoghan Ryan.

An abstract is a short summary of a longer work (such as a thesis ,  dissertation or research paper ). The abstract concisely reports the aims and outcomes of your research, so that readers know exactly what your paper is about.

Although the structure may vary slightly depending on your discipline, your abstract should describe the purpose of your work, the methods you’ve used, and the conclusions you’ve drawn.

One common way to structure your abstract is to use the IMRaD structure. This stands for:

• Introduction

Abstracts are usually around 100–300 words, but there’s often a strict word limit, so make sure to check the relevant requirements.

In a dissertation or thesis , include the abstract on a separate page, after the title page and acknowledgements but before the table of contents .

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Table of contents

Abstract example, when to write an abstract, step 1: introduction, step 2: methods, step 3: results, step 4: discussion, tips for writing an abstract, other interesting articles, frequently asked questions about abstracts.

Hover over the different parts of the abstract to see how it is constructed.

This paper examines the role of silent movies as a mode of shared experience in the US during the early twentieth century. At this time, high immigration rates resulted in a significant percentage of non-English-speaking citizens. These immigrants faced numerous economic and social obstacles, including exclusion from public entertainment and modes of discourse (newspapers, theater, radio).

Incorporating evidence from reviews, personal correspondence, and diaries, this study demonstrates that silent films were an affordable and inclusive source of entertainment. It argues for the accessible economic and representational nature of early cinema. These concerns are particularly evident in the low price of admission and in the democratic nature of the actors’ exaggerated gestures, which allowed the plots and action to be easily grasped by a diverse audience despite language barriers.

Keywords: silent movies, immigration, public discourse, entertainment, early cinema, language barriers.

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You will almost always have to include an abstract when:

• Completing a thesis or dissertation
• Submitting a research paper to an academic journal
• Writing a book or research proposal
• Applying for research grants

It’s easiest to write your abstract last, right before the proofreading stage, because it’s a summary of the work you’ve already done. Your abstract should:

• Be a self-contained text, not an excerpt from your paper
• Be fully understandable on its own
• Reflect the structure of your larger work

Start by clearly defining the purpose of your research. What practical or theoretical problem does the research respond to, or what research question did you aim to answer?

You can include some brief context on the social or academic relevance of your dissertation topic , but don’t go into detailed background information. If your abstract uses specialized terms that would be unfamiliar to the average academic reader or that have various different meanings, give a concise definition.

After identifying the problem, state the objective of your research. Use verbs like “investigate,” “test,” “analyze,” or “evaluate” to describe exactly what you set out to do.

This part of the abstract can be written in the present or past simple tense  but should never refer to the future, as the research is already complete.

• This study will investigate the relationship between coffee consumption and productivity.
• This study investigates the relationship between coffee consumption and productivity.

Next, indicate the research methods that you used to answer your question. This part should be a straightforward description of what you did in one or two sentences. It is usually written in the past simple tense, as it refers to completed actions.

• Structured interviews will be conducted with 25 participants.
• Structured interviews were conducted with 25 participants.

Don’t evaluate validity or obstacles here — the goal is not to give an account of the methodology’s strengths and weaknesses, but to give the reader a quick insight into the overall approach and procedures you used.

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Next, summarize the main research results . This part of the abstract can be in the present or past simple tense.

• Our analysis has shown a strong correlation between coffee consumption and productivity.
• Our analysis shows a strong correlation between coffee consumption and productivity.
• Our analysis showed a strong correlation between coffee consumption and productivity.

Depending on how long and complex your research is, you may not be able to include all results here. Try to highlight only the most important findings that will allow the reader to understand your conclusions.

Finally, you should discuss the main conclusions of your research : what is your answer to the problem or question? The reader should finish with a clear understanding of the central point that your research has proved or argued. Conclusions are usually written in the present simple tense.

• We concluded that coffee consumption increases productivity.
• We conclude that coffee consumption increases productivity.

If there are important limitations to your research (for example, related to your sample size or methods), you should mention them briefly in the abstract. This allows the reader to accurately assess the credibility and generalizability of your research.

If your aim was to solve a practical problem, your discussion might include recommendations for implementation. If relevant, you can briefly make suggestions for further research.

If your paper will be published, you might have to add a list of keywords at the end of the abstract. These keywords should reference the most important elements of the research to help potential readers find your paper during their own literature searches.

Be aware that some publication manuals, such as APA Style , have specific formatting requirements for these keywords.

It can be a real challenge to condense your whole work into just a couple of hundred words, but the abstract will be the first (and sometimes only) part that people read, so it’s important to get it right. These strategies can help you get started.

Read other abstracts

The best way to learn the conventions of writing an abstract in your discipline is to read other people’s. You probably already read lots of journal article abstracts while conducting your literature review —try using them as a framework for structure and style.

You can also find lots of dissertation abstract examples in thesis and dissertation databases .

Reverse outline

Not all abstracts will contain precisely the same elements. For longer works, you can write your abstract through a process of reverse outlining.

For each chapter or section, list keywords and draft one to two sentences that summarize the central point or argument. This will give you a framework of your abstract’s structure. Next, revise the sentences to make connections and show how the argument develops.

Write clearly and concisely

A good abstract is short but impactful, so make sure every word counts. Each sentence should clearly communicate one main point.

To keep your abstract or summary short and clear:

• Avoid passive sentences: Passive constructions are often unnecessarily long. You can easily make them shorter and clearer by using the active voice.
• Avoid long sentences: Substitute longer expressions for concise expressions or single words (e.g., “In order to” for “To”).
• Avoid obscure jargon: The abstract should be understandable to readers who are not familiar with your topic.
• Avoid repetition and filler words: Replace nouns with pronouns when possible and eliminate unnecessary words.
• Avoid detailed descriptions: An abstract is not expected to provide detailed definitions, background information, or discussions of other scholars’ work. Instead, include this information in the body of your thesis or paper.

If you’re struggling to edit down to the required length, you can get help from expert editors with Scribbr’s professional proofreading services or use the paraphrasing tool .

Check your formatting

If you are writing a thesis or dissertation or submitting to a journal, there are often specific formatting requirements for the abstract—make sure to check the guidelines and format your work correctly. For APA research papers you can follow the APA abstract format .

Checklist: Abstract

The word count is within the required length, or a maximum of one page.

The abstract appears after the title page and acknowledgements and before the table of contents .

I have clearly stated my research problem and objectives.

I have briefly described my methodology .

I have summarized the most important results .

I have stated my main conclusions .

I have mentioned any important limitations and recommendations.

The abstract can be understood by someone without prior knowledge of the topic.

You've written a great abstract! Use the other checklists to continue improving your thesis or dissertation.

If you want to know more about AI for academic writing, AI tools, or research bias, make sure to check out some of our other articles with explanations and examples or go directly to our tools!

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An abstract is a concise summary of an academic text (such as a journal article or dissertation ). It serves two main purposes:

• To help potential readers determine the relevance of your paper for their own research.
• To communicate your key findings to those who don’t have time to read the whole paper.

Abstracts are often indexed along with keywords on academic databases, so they make your work more easily findable. Since the abstract is the first thing any reader sees, it’s important that it clearly and accurately summarizes the contents of your paper.

An abstract for a thesis or dissertation is usually around 200–300 words. There’s often a strict word limit, so make sure to check your university’s requirements.

The abstract is the very last thing you write. You should only write it after your research is complete, so that you can accurately summarize the entirety of your thesis , dissertation or research paper .

Avoid citing sources in your abstract . There are two reasons for this:

• The abstract should focus on your original research, not on the work of others.
• The abstract should be self-contained and fully understandable without reference to other sources.

There are some circumstances where you might need to mention other sources in an abstract: for example, if your research responds directly to another study or focuses on the work of a single theorist. In general, though, don’t include citations unless absolutely necessary.

The abstract appears on its own page in the thesis or dissertation , after the title page and acknowledgements but before the table of contents .

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Step-by-step guide to critiquing research. Part 2: Qualitative research

Affiliation.

• 1 School of Nursing and Midwifery, University of Dublin, Trinity College, Dublin, Ireland, UK.
• PMID: 17851363
• DOI: 10.12968/bjon.2007.16.12.23726

As with a quantitative study, critical analysis of a qualitative study involves an in-depth review of how each step of the research was undertaken. Qualitative and quantitative studies are, however, fundamentally different approaches to research and therefore need to be considered differently with regard to critiquing. The different philosophical underpinnings of the various qualitative research methods generate discrete ways of reasoning and distinct terminology; however, there are also many similarities within these methods. Because of this and its subjective nature, qualitative research it is often regarded as more difficult to critique. Nevertheless, an evidenced-based profession such as nursing cannot accept research at face value, and nurses need to be able to determine the strengths and limitations of qualitative as well as quantitative research studies when reviewing the available literature on a topic.

Publication types

• Anthropology, Cultural
• Data Collection / ethics
• Data Collection / methods
• Data Interpretation, Statistical
• Evidence-Based Medicine
• Guidelines as Topic
• Interviews as Topic
• Nursing Methodology Research / ethics
• Nursing Methodology Research / organization & administration*
• Nursing Theory
• Philosophy, Nursing
• Qualitative Research*
• Reproducibility of Results
• Research Design*

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Case Summary: Brigidi, Gian-Stefano

Gian-Stefano Brigidi, Ph.D. University of California San Diego and University of Utah : Based on the report of an assessment conducted by the University of Utah (UU), and inquiry conducted by the University of California San Diego (UCSD), the Respondent’s admission, and additional analysis conducted by the Office of Research Integrity (ORI) in its oversight review, ORI found that Gian-Stefano Brigidi, Ph.D. (Respondent), who was a Postdoctoral Fellow, Department of Neurobiology, UCSD, and was an Assistant Professor, Department of Neurobiology, UU, engaged in research misconduct in research supported by U.S. Public Health Service (PHS) funds, specifically National Institute of Mental Health (NIMH), National Institutes of Health (NIH), grant F32 MH110141, National Human Genome Research Institute (NHGRI), NIH, grant T32 HG000044, National Institute of Neurological Disorders and Stroke (NINDS), NIH, grant P30 NS047101, and National Library of Medicine (NLM), NIH, grant T15 LM011271. The research was included in grant applications submitted for PHS funds, specifically R01 NS131809-01, R01 NS133405-01, DP2 NS127276-01, and R01 NS111162-01A1 submitted to NINDS, NIH, and R21 MH121860-01, R21 MH121860-01A1, F32 MH110141-01, F32 MH110141-01A1, and F32 MH110141-01AS1 submitted to NIMH, NIH.

ORI found that Respondent engaged in research misconduct by knowingly or intentionally falsifying and/or fabricating data and results by manipulating primary data values to falsely increase the n-value, manipulating fluorescence micrographs and their quantification graphs to augment the role of ITFs in murine hippocampal neurons, and/or manipulating confocal images that were obtained through different experimental conditions in twenty (20) figures of one (1) published paper and four (4) PHS grant applications, one (1) panel of one (1) poster, and seven (7) slides of one (1) presentation:  

• Genomic Decoding of Neuronal Depolarization by Stimulus-Specific NPAS4 Heterodimers. Cell . 2019 Oct 3;179(2):373-391.e27. doi: 10.1016/j.cell.2019.09.004 (hereafter referred to as “ Cell 2019”).  
• Genomic mechanisms linking neuronal activity history with present and future functions. Poster for “The Brigidi Lab – a neuronal activity lab in the Department of Neurobiology at the University of Utah” (hereafter referred to as the “UU Department of Neurobiology poster”).  
• Decoding neural circuit stimuli into spatially organized gene regulation. Presentation presented to the UU Department of Neurobiology & Anatomy on January 23, 2020 (hereafter referred to as “UU Department of Neurobiology presentation”).   
• DP2 NS127276-01, “Decoding neuronal activity history at the genome through the spatially segregated inducible transcription factors,” submitted to NINDS, NIH, on August 20, 2020, Awarded Project Dates: September 15, 2021-August 1, 2023.   
• F32 MH110141-01, “Regulation of excitatory-inhibitory balance by the local translation of the immediate early gene Npas4,” submitted to NIMH, NIH, on August 10, 2015.   
• F32 MH110141-01A1, “Regulation of Excitatory-Inhibitory Balance by Local Translation of the Immediate Early Gene Npas4,” submitted to NIMH, NIH, on December 8, 2015, Awarded Project Dates: August 1, 2016-July 31, 2018.   
• F32 MH110141-01A1S1, “Regulation of Excitatory-Inhibitory Balance by Local Translation of the Immediate Early Gene Npas4,” submitted to NIMH, NIH, on December 8, 2016, Awarded Project Dates: December 1, 2016-July 31, 2017.  

The falsified and/or fabricated data also were included in twenty-three (23) figures in the following five (5) PHS grant applications:  

• R01 NS131809-01, “Regulation and function of dendritic mRNA that encodes the neuronal transcription factor Npas4,” submitted to NINDS, NIH, on June 6, 2022.   
• R01 NS133405-01, “Assessing the impact of the inducible transcription factor NPAS4 on spatial tuning in the mouse hippocampus,” submitted to NINDS, NIH, on October 5, 2022.   
• R01 NS111162-01A1, “Molecular and cellular mechanisms underlying activity dependent gene regulation in neurons,” submitted to NINDS, NIH, on March 5, 2019, Awarded Project Dates: December 15, 2019-November 30, 2024.   
• R21 MH121860-01, “Identification of dendritically-localized transcription factor mRNAs as a mechanism for conveying multiple streams of information to the nucleus,” submitted to NIMH, NIH, on February 19, 2019.   
• R21 MH121860-01A1, “Identification of dendritically-localized transcription factor mRNAs,” submitted to NIMH, NIH, on March 16, 2020. 

Specifically,   ORI found that:  

• Respondent knowingly or intentionally combined two to three real data sets and two to five fabricated data sets to falsely increase the n-values reported in:    
• Figures 1B, 1D, 1E, 1G, 1I, 1J, 1M-1O, 1Q-1T, S2B-S2D, S2F-S2H, S3I, S3L, S3M, and S6H of Cell 2019 and Slides 6-10, 13, and 28 of the UU Department of Neurobiology presentation representing the quantification of NPAS4 immunohistofluorescence

Figures 2H, 2I, 2K, 2P, 3C, 3E, 4D-4G, 4K-4N, 4P-4Q, S3G, S5B, and S5C of Cell  2019 representing the quantification of Npas4 mRNA or puro-PLA puncta 

• Figures S1E, S1G, and S1H of Cell  2019 representing the quantification of whole-cell clamp recordings of CA1 PN
• Figures 2 (lower panel) and 3c of F32 MH110141-01, Figures 1g, 2b, 2d, and 4 of F32 MH110141-01A1S1, and Figures 1g, 2b, 2d, and 4 of F32 MH110141-01A1 representing time points of NPAS4 quantification after no stimulation or post-stimulation in the alveus or radiatum SR, SO, SP, SLM, with or without the addition of an inhibitor
• Respondent knowingly or intentionally manipulated confocal images that were obtained through different experimental conditions in: 

Figures 1A, 1C, and 1F of Cell 2019 and Slides 6-9 of the UU Department of Neurobiology presentation representing confocal images of hippocampal slices immunostained for NPAS4 and Neu

Figures S2A and S2E of Cell 2019 by manipulating and misrepresenting the GFP signals as NPAS4 signals in wildtype mice 

Figures 1H, 1L, 1P, S3K, S6F, and S6G of Cell 2019 and Slides 9 and 28 of the UU Department of Neurobiology presentation by manipulating the raw images of hippocampal slices immunostained with NPAS4 and Neu and/or ARNT1 or ARNT2 by generating a mask of NPAS4 immunofluorescent signal through GFP signal from tissue obtained from Thy1-GFP mice to intentionally enhance the appearance of the dendritic NPAS4 signal

Figures S6F and S6G of Cell 2019 by manipulating the raw images of hippocampus slices by overlaying a GFP channel over ARNT1 channel and using the multiply feature in Photoshop to restrict ARNT1 signal through GFP to enhance the ARNT1 signal in three panels

• Slides 7, 9, and 28 of the UU Department of Neurobiology presentation by manipulating six images representing post-stimulation with different time points by using a GFP mask overlaid on top of raw NPAS4 immunofluorescence

Figure 4 of DP2 NS127276-01 and panel 1 of the UU Department of Neurobiology poster representing twelve images in columns 2-4 labeled EGR, FOS, ATF4 by mislabeling the microscope images as immunofluorescent stained with antibodies against EGR, FOS, and ATF4 when they actually were stained with anti-NPAS4 and selected images to support the immunofluorescence data in the ITF induction graphs 

Figure 5 of DP2 NS127276-01 representing two confocal images in the far-right column by intentionally and selectively enhancing the brightness of the anti-NPAS4 immunofluorescent channel within the dashed box and left brightness unchanged in surrounding areas of the images 

Figure 6 of DP2 NS127276-01 in twelve images in columns 2-5 labeled Egr2 , Fos , and Atf4 by intentionally mislabeling the microscope images as RNA in situ hybridization with probes against Egr2, Fos, and Atf4 when they actually were stained with NPAS4 probes and intentionally selecting and quantifying images in the quantification graphs to support the conclusions of the grant application

Respondent knowingly or intentionally manipulated the fluorescence micrographs and their quantification graphs to augment the role of ITFs in murine hippocampal neurons in Figures 2B-2G, 2J, 2L-2O, 3B, 3D, 3F-3H, 4C, 4J, 4O, S1A-S1D, S1F, S1I-S1J, S3A-S3F, S3H, S3J, S3N-S3T, S5D-S5G, and S6A-S6E of Cell  2019; the falsified/fabricated data also were included in Figures 2B-2H, 3, 4B-4E, and 5C-5G of R21 MH121860-01, Figures 2, 3B-3E, 4B-4C, 4E-4I, and 5B-5E of R21 MH121860-01A1, Figures 3, 5, 6B, 7, 8, 10B-10D, 11A-11C, and 11E-11F in R01 NS131809-01, Figure 8 of R01 NS133405-01, and Figures 3B-3C, 3E-3I, 4B-4I, 5, 9, 10B-10E, and 11-12 of R01 NS111162-01A1.

Respondent entered into a Voluntary Settlement Agreement (Agreement) and voluntarily agreed to the following:  

• Respondent will have his research supervised for a period of five (5) years beginning on March 24, 2024 (the “Supervision Period”). Prior to the submission of an application for PHS support for a research project on which Respondent’s participation is proposed and prior to Respondent’s participation in any capacity in PHS-supported research, Respondent will submit a plan for supervision of Respondent’s duties to ORI for approval. The supervision plan must be designed to ensure the integrity of Respondent’s research. Respondent will not participate in any PHS-supported research until such a supervision plan is approved by ORI. Respondent will comply with the agreed-upon supervision plan.  
• A committee of 2-3 senior faculty members at the institution who are familiar with Respondent’s field of research, but not including Respondent’s supervisor or collaborators, will provide oversight and guidance for a period of five (5) years from the effective date of the Agreement. The committee will review primary data from Respondent’s laboratory on a quarterly basis and submit a report to ORI at six (6) month intervals setting forth the committee meeting dates and Respondent’s compliance with appropriate research standards and confirming the integrity of Respondent’s research.

The committee will conduct an advance review of each application for PHS funds, or report, manuscript, or abstract involving PHS-supported research in which Respondent is involved. The review will include a discussion with Respondent of the primary data represented in those documents and will include a certification to ORI that the data presented in the proposed application, report, manuscript, or abstract are supported by the research record. 

• During the Supervision Period, Respondent will ensure that any institution employing him submits, in conjunction with each application for PHS funds, or report, manuscript, or abstract involving PHS-supported research in which Respondent is involved, a certification to ORI that the data provided by Respondent are based on actual experiments or are otherwise legitimately derived and that the data, procedures, and methodology are accurately reported and not plagiarized in the application, report, manuscript, or abstract.
•   If no supervision plan is provided to ORI, Respondent will provide certification to ORI at the conclusion of the Supervision Period that his participation was not proposed on a research project for which an application for PHS support was submitted and that he has not participated in any capacity in PHS-supported research.
•   During the Supervision Period, Respondent will exclude himself voluntarily from serving in any advisory or consultant capacity to PHS including, but not limited to, service on any PHS advisory committee, board, and/or peer review committee.
•   Respondent will request that the following paper be corrected or retracted:
• Cell. 2019 Oct 3;179(2):373-391.e27. doi: 10.1016/j.cell.2019.09.004

Respondent will copy ORI and the Research Integrity Officer at UCSD on the correspondence with the journal.

A Federal Register notice (FRN) has been submitted to the Federal Register for this case. When the FRN is published in the Federal Register ,  the link will be provided here.

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Modeling collective behaviors from optic flow and retinal cues

Diego castro, franck ruffier, and christophe eloy, phys. rev. research 6 , 023016 – published 4 april 2024.

• No Citing Articles

Supplemental Material

• INTRODUCTION
• NUMERICAL SIMULATIONS
• CONCLUSIONS

Animal collective behavior is often modeled with self-propelled particles, assuming each individual has “omniscient” knowledge of its neighbors. Yet, neighbors may be hidden from view and we do not know the effect of this information loss. To address this question, we propose a visual model of collective behavior where each particle moves according to bioplausible visual cues, in particular the optic flow. This visual model successfully reproduces three classical collective behaviors: swarming, schooling, and milling. This model offers a potential solution for controlling artificial swarms visually.

• Received 10 May 2023
• Accepted 16 February 2024

DOI: https://doi.org/10.1103/PhysRevResearch.6.023016

Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

Published by the American Physical Society

Physics Subject Headings (PhySH)

• Research Areas
• Physical Systems

Authors & Affiliations

• 1 Aix Marseille Université, CNRS, ISM, Marseille, 13288 France
• 2 Aix Marseille Université, CNRS, Centrale Med, IRPHE, Marseille, 13013 France
• * [email protected]

Article Text

Vol. 6, Iss. 2 — April - June 2024

Subject Areas

• Biological Physics
• Soft Matter

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Notations used and principle of the visual cues. (a) The particle i is located in x i and θ i is its heading. θ i j is the retinal position of particle j for the i th particle. (b) The angle ϕ is the line of sight with respect to the particle's heading. The vector V i j = U ( e j − e i ) is the relative velocity of particle j perceived by i . It can be decomposed into radial and azimuthal components, V i r and V i ϕ . (c) Point of view of the particle i , the arrows represent the optic flow generated by the relative angular velocity of each particle. (d) The visual field V i ( φ ) is a binary representation of (c). It is formed of a set of “shades.” (e) The function R i ( ϕ ) represents the estimated distance associated to shades, assuming they are associated with a single individual of radius a . (f) Optic flow O i ( ϕ ) associated with the apparent angular velocity of the shade edges. (g) Optic flow divergence D i ( ϕ ) .

Illustration of the phases observed for N = 50 individuals. The scale bar measures 30 a in total ( 10 a for each section). The parameters ε = 1 and k η = 0.01 are fixed. We observe three phases when varying the other two parameters: (a) swarming ( k ⊙ = 0.1 ,   k ∥ = 0 ); (b) schooling ( k ⊙ = 0.06 ,   k ∥ = 0.2 ); and (c) milling ( k ⊙ = 0.1 ,   k ∥ = 0.04 ).

Phase diagrams for N = 50 individuals and noise strength k η = 0.01 . These phase diagrams compare the visual model (a), (b) and the omniscient model (c), (d) for ε = 0 (a), (c) and ε = 1 (b), (d). The colors represent different values of P and M as shown in (e). The contours show the values of opacity O (white solid), the line M = 0.5 (white dotted), and P = 0.5 (white dashed).

Example of the bistability observed in the visual model (parameter values: ε = 1 ,   k ⊙ = 0.1 , k ∥ = 0.2 , and k η = 0.01 ). (a) Time series of the three metrics P ,   M , and O . (b) Trajectories of the collective behavior in the ( M , P ) plane. Illustration of the phases: (c) schooling-milling transition; (d) milling; (e) milling-schooling transition; and (f) schooling.

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Physical Review Research

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Failure of an effective stress approach in polydisperse wet granular materials

David cantor, emilien azéma, and carlos ovalle, phys. rev. research 6 , l022008 – published 8 april 2024.

• No Citing Articles

Supplemental Material

• ACKNOWLEDGMENTS

In this Letter, the effective stress principle (ESP)—originally developed for granular materials saturated with water and recently extended to unsaturated ones via simulations—is shown to fail once the material presents wide grain size distributions. We demonstrate that the current ESP approaches cannot capture the Mohr-Coulomb strength parameters as soon as the grain size span exceeds d max / d min ∼ 4 . This failure is attributed to significant differences in the fabric generated by solid interactions in the wet material, which are supposedly capable of matching the characteristics of the dry material. We show that a generalization of the ESP requires not only macroscopic considerations but also direct attention to the nature of contact and force networks.

• Received 17 June 2023
• Accepted 23 January 2024

DOI: https://doi.org/10.1103/PhysRevResearch.6.L022008

Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

Published by the American Physical Society

Physics Subject Headings (PhySH)

• Research Areas
• Physical Systems

Authors & Affiliations

• 1 Department of Civil, Geological, and Mining Engineering, Polytechnique Montréal H3T 1J4, Canada
• 2 Research Institute on Mining and Environment, RIME UQAT-Polytechnique, Montréal H3T 1J4, Canada
• 3 LMGC, Université de Montpellier, CNRS, Montpellier 34090, France
• 4 Institut Universitaire de France (IUF), Paris 75005, France
• * [email protected]
• † [email protected]
• ‡ [email protected]

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Vol. 6, Iss. 2 — April - June 2024

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• Soft Matter
• Statistical Physics

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Evolution of the macroscopic friction angle sin ( ϕ ) and (inset) the cohesion c for the dry material (black circles), the constant force interaction law (green triangles), the wet law (red rectangles), and the solid contact stress tensor (orange crosses) as a function of particle size span S .

Evolution of the capillary mean pressure p cap and deviatoric stress q cap as a function of S . Averaged values are shown since the different levels of η (shown in transparency) do not affect the tensor σ i j cap .

Evolution of the macroscopic cohesion c and its prediction using the capillary stress tensor and the ESP as a function of the grain size span S . Inset: comparison between the ratio q / p for the dry material and “cont” network as a function of S .

Evolution of anisotropies linked to (a) contact orientations a c , (b) normal forces a n , (c) tangential forces a t , and (d) branch lengths for the dry material (displayed with a black line) and the “cont” network for increasing level of cohesive scale η .

Slices of the samples with particle size span S = 0.8 at level of deformation ɛ = 0.3 , highlighting the grains carrying forces in gray and the floating particles in red for the (a) dry and (b) wet materials. For the latter case, grains that do not participate in the solid contact network are shown in green.

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