The descriptive or indicative abstract, identifies the contents of the research or the basic subject of the article, demonstrating the paper’s organization without providing results or conclusions. Thus, it is not very informative. This type of abstract is always very short, usually under 100 words; and it is useful for a long report. On the other hand, the informative abstract, which is also known simply as a summary, gives the principal argument and summarizes the principal data, providing the reader with an overview of the objectives, methods, results and conclusions of the study. So, be specific. You may also have heard of a “structured abstract” — this is a subtype of the informative abstract which has more than one paragraph.
The abstract presents the information in four general sections: introduction, methods, results and conclusions. It is worth noting that an abstract is only text and follows strictly the logical order of the paper. That is, the abstract ought to parallel the structure of the original paper. At the same time, it adds NO new information, i. e. that is not stated in the paper. Now notice that the abstract can be viewed as an independent document. It is because of this that it should be unified, coherent (i.e. providing appropriate transitions or logical linkage between the information included), concise, and able to stand alone. In other words, the abstract should be complete in itself.
What to include?
The content of the abstract includes:
Motivation and purpose: main subject or research question and review of the relevant literature.
Specifics: problem statement, approach, objectives, hypothesis, research methodology (method(s) adopted or search strategies).
Results: main findings (proposed solutions to the problem) and discussion.
Conclusions and implications/outcomes: what the results mean and further points.
As we can see, the abstract must state:
1. The problem addressed and some background information.
2. The solution or insight proposed (newly observed facts).
3. An example that shows how it works.
4. An evaluation: a comparison with existing answers/techniques.
Then, an abstract should provide answers for the following questions:
• What and why.
• What you found.
• How you did it.
• But how do we begin?
What would be an effective way to begin an abstract? To help you on your way let us consider some introductory sentences.
First, let us see some opening sentences that DO NOT offer real information:
• This paper reports on a method for…
• The paper explores the notions of…
• The purpose of our research is to consider how…
• The objective of this study is to determine…
• Thus, it is clear that you should avoid writing a statement of scope.
On the other hand, the sentences bellow represent good examples of introductory statements, for they go directly into the subject. They give something to the reader. Let us see how it works:
The development process of hypermedia and web systems poses very specific problems that do not appear in other software applications, such as…
Given a large set of data, a common data mining problem is to extract the frequent patterns occurring in this set.
According to many recent studies the effect of learning style on academic performance has been found to be significant and mismatch between teaching and learning styles causes learning failure and frustration.
Do’s and don’ts of abstract writing
Do write a single paragraph.
Do meet the specific word length.
Do answer the questions: what, why, and how.
Do use familiar language to the reader.
Do use a few keywords.
Do write short sentences.
Do improve transitions between the sentences.
Do use active voice.
Do use third person singular.
Do begin with a clear introductory statement written in the present tense.
Do use past tense in the main body.
Do write a concluding statement in the present tense: just tells what the results mean (e.g. “These results suggest…”).
Do fix grammar.
Do use headings, subheadings and tables as a guide for writing.
Do print and reread the abstract.
Don’t cite the sections of the paper.
Don’t include references to the literature and to figures and tables.
Don’t use abbreviations.
Don’t add new information.
Don’t add superfluous information.
Don’t add opinions.
Don’t repeat information.
Don’t repeat the article title.