Introduction Outline
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I. General Comments
 

The larger part of the introduction of a research paper describes past studies that led to your experiment. Perhaps your study is based on questions left unanswered in previous studies. Often you may replicate an earlier study using a new procedure. In any case, your introduction should clearly point out findings and weaknesses in past experiments to justify conducting your study.

Abstract the important information from each article first. Then, and this is even more important, write a concise, coherent, logical summary of the information in your own words. Do not use an outline format. Equally important, do not assume that your reader is the instructor; I already know what you are writing about. Rather, your reader is some stranger who may not know the studies you are describing, and your literature review should make sense to him or her. The best strategy is to give your introduction to someone who is not in the class and ask this person whether the logical structure and the content makes sense. If this
person cannot follow your arguments, then you still have work to do.

Organizing your introduction in a logical manner, progressing from very general findings to findings that are specifically related to the study you have conducted is extremely important. One common approach is to describe past experiments in chronological order of publication, because your study will usually be based on more recent findings. Another useful framework is to compare and contrast studies which support alternative theoretical explanations for the relationship you are interested. If you are confused as to how an introduction should flow, then a good idea is to find a journal article that you think was well written and use that as a
"conceptual model" to structure your own introduction.

You should be able to integrate the information into concise paragraphs that are no longer than four or five sentences. Each paragraph must have a topic sentence that links the paragraph to the others. You need only cite relevant findings and make sure you briefly mention the manipulations. The impression your should draw from these suggestions is that good introductions take some work. Do not expect to do a “one draft” introduction. The extra time you put into this section will be favorably reflected in your grade. If you have problems, then please ask for help.

After you have established the historical and/or theoretical context for your experiment, you conclude the introduction by presenting the purpose and experimental hypotheses of your study. You should also briefly describe the procedures you used to manipulate the independent variables and to measure the dependent variables.

A special comment about length. Good introductions are very concise. Only the information that is relevant to the research question and design that you use is abstracted from each past study. For this reason, each study should be described in about a paragraph (not a page or page and a half paragraph!). If your summary of a study runs more than 1/2 or 3/4 of a page, then the summary is much too long. Get our your red pen and delete any unessential information, such as the number of participants or where they were from, overly detailed descriptions of the manipulations and measures. Also, you should notice sentences that could be combined to decrease the chance you are being “wordy.” Your introductions should be based on a “framework” that organizes and integrates the material to be cited. Think of the framework as a “wide-angle” view of the introduction that makes explicit how references are to be used. The frame work is absolutely essential if your desired goal is a logical, coherent, and progressively more specific narrative.


II. Citations

In the introduction section, in particular, you MUST cite past research that supports the statements you make or tells the reader where the basis of your idea orginated. If you cite no one in the introduction, then you are by far the most knowing person in social-behavioral research that I know. The table below contains the basic rules governing citations as a function of the number of authors.



From Basics of APA Style Tutorial (2009) available from http://flash1r.apa.org/apastyle/basics/index.htm


III. Citations within the Introduction

Within a paragraph, when the name of the author is part of the text or narrative (i.e., nonparenthetical citations), you only use the year of publication for the first citation. For example,

            Whatley (2009) published an article examining the gender differences in the tendency to procrastinate. Whatley found that...

In parenthetical citations where the citation(s) appear within parentheses, you always include the year. For example:

             The two more prominent situational characteristics that influence procrastinatory behavior involve temporal and aversive
             characteristics (Loewenstein, 1992). For example, research has shown that the further away the deadline is the more likely
             people will engage in procrastinatory behavior (e.g., Loewenstein, 1992).

Please remeber that anything contained with parentheses is nothing more than supporting documentation. The information within parentheses is not part of the sentence structure (i.e., it does not function as a noun, verb, adjective, etc.).        


IV. Organization and Content of the Introduction

The introduction has no formal sections. However, you should proceed logically and coherently through each study in the literature review, using transition words and phrases to emphasize the connections between important ideas. Point out the main hypotheses, results
and conclusions for each experiment. Briefly describe the manipulations and measures, particularly when they are important for interpreting the results. Try to reduce each article to an “abstract” containing the most essential information to background your study, but DO NOT simply copy the abstract from the article! Remember to describe the results in words only, no numbers.


Title of Report
(should be the same as the title on the title page)

A.     Begin the introduction with a general statement about the relationship of interest. An example might be:

                                Research on physical attractiveness has shown that attractive individuals have many interpersonal advantages over unattractive individuals.

B.     Write the literature review. Describe each study, for example:

    1. Downs and Lyons (1991)

Example of
a Reviewed
Study
             The effect of the defendant's attractiveness on guilt also affects the legal system. For example, Downs and Lyons (1991) conducted a study to determine whether judges are affected by physical appearance. The researchers collected data on the bail amount assigned to defendants by judges. Next, police officers not involved with the case were asked to rate the attractiveness of the defendant in actual court cases. The results showed that attractive defendants were given significantly lower bail amounts compared to attractive defendants. These results suggest that an attractiveness bias is present in the legal system.

 
    2. Efran (1974).

Example of
a Topic Sentence

             Physical attractiveness also appears to effect the evaluations of transgressions by adults, even though most people believe that decisions should not be based on irrelevant information, such as appearance. Efran
(1974) found ...


C.     End the introduction with a statement of the purpose, variables, and hypotheses of  your study. You will need to describe the participant sample (college
         undergraduates, etc.), the nature of their task including your independent and dependent variables, and your predictions. A good example of a purpose and
         hypothesis paragraph is presented below.

Example of
a Purpose and  Hypothesis Paragraph

             The purpose of this study was to examine further the relationship between physical attractiveness and judgments of criminal behavior. Participants read newspaper accounts of a robbery by a woman described as physically attractive or unattractive. All participants then rated the degree of guilt and length of prison sentence. I expected that judgments of the defendant would be influenced by her physical attractiveness (e.g., Dion et al., 1972). Specifically, I predicted that an attractive versus unattractive defendant would be viewed as less guilty (Efran, 1974). Also, I predicted that an attractive defendant would receive a shorter prison sentence than an unattractive defendant (Efran, 1974).



        Please note that where applicable I have referenced studies that provide support for each  of my hypotheses.