How
to Write a
Psychology Experiment Report
Rational
Communication is a critical step in the Scientific Method. Peer-reviewed journal articles are one of the standard forms of this communication. Journal articles have evolved a standard style that increases understanding while decreasing reading time. However, readers must be aware of the conventions. Writing a report of a student’s experiment provides an opportunity to learn this standard form through experience. This exercise should increase student understanding of Psychology reports while developing student ability to communicate both clearly and precisely.
To begin student familarity with journal reports, students should read several examples. A list of suggested readings should be made available to facilitate this effort.
Sections required for the Semester Project are noted by this mark:
.
General style
Psychology
Experimental Reports and Journal Articles are always
written in the past tense, third person, passive voice. For example, "Eighteen students were
tested on a color perception task" or "A study was conducted to
identify the factors contributing to teenage drug use ".
Title
Titles
should be be short, specific topic statements. Example titles might include:
"Classically Conditioning a Cat to avoid Visual Stimuli" or
"Decreasing nail biting frequency using Operant Conditioning". If
several words are required for clarity, multi-part titles may be used. An
example of a multi-part title is: "Failure of Punishment: A study using
Classical Conditioning in a Day Care Setting".
Remember that titles act as an advertisement for your report. Just as in popular magazines, readers decide whether or not to read more based on whether the title interests them. In Scientific writing your goal is to use the title to interest readers in the abstract (next).
Abstract
An
abstract is the shortest section of an article. It is also the most
important. The abstract is often the only section of a report that they will read.
Researchers often use abstracts to decide whether or not to take time to read
the body of the report. On-line and electronic repositories of Psychology
reports generally contain only the abstract, - not the full text of the report.
Abstracts are a testimonial. They give the reader an accurate but terse outline of what was done, what the results were, what the take home message is, and why you bothered in the first place. Never use more than 200 words — people will get bored. Aim for 150 or less.
Aim
for 50 to 100 words
Example of a good abstract (from Dickinson, Campos, Varga & Balleine, 1996):
"Three experiments examined bidirectional instrumental conditioning by training hungry rats to push a pole in one direction for food pellets and in the other for either a starch or sugar solution. In the first study, we examined whether animals learned about the action-reinforcer relations using a specific satiety procedure. Prefeeding one type of reinforcer before an extinction test selectively depressed the performance of the action that had been paired with this reinforcer during training. The second experiment investigated the sensitivity of the bidirectional action to variations in the action-reinforcer contingencies. When the instrumental contingency was degraded by presenting unpaired reinforcers, the animals pushed less in the direction that was paired with the reinforcer type that was the same as the non-contiguous one. A third study revealed that increasing the rate of reinforcement for one action enhanced its rate of performance without significantly affecting the performance of the other action. We conclude that the effects of reinforcer devaluation, the action-outcome contingency, and the rate of reinforcement are not mediated by Pavlovian associations between the manipulandum and the reinforcer"
Note how the author has introduced, described and concluded from three experiments in less than 200 words. Also note the level of understanding expected from the reader. He or she is expected to know common terms in psychology such as "instrumental conditioning", "reinforcer" and "Pavlovian". The reader is also expected to have a large general vocabulary (e.g. "contiguous"). However, he or she is not expected to know terms specific to the particular experiments performed — terms such as "specific satiety" and "bidirectional conditioning" these are explained in the abstract.
This assumption about level of understanding will pervade the whole article.
Introduction
In
many good reports, the introduction
is a defence of the experiments performed. An introduction should be the answer
to the following reasonable questions the reader should have:
What
do the experiments have the potential to tell us?
How
do they fit in with research on related topics, and what do they add?
The introduction also provides the reader with the specialist information required to make sense of the experiments. For example, an explanation of contrasting theories tested by the experiment may be required.
Writing a good scientific paper is like story-telling. The role of the introduction, like the first chapter of a novel, is to engage interest, provide context, and set the scene. By the time your reader reaches the end of the introduction, he or she should be able to predict (in general terms) what experiment you’re going to describe in the Method section, and what the desired outcome(s) might be.
Introductions do not need to be long. They often tend to be long in practice but this should not be considered desirable. An introduction is not a literature review. Only talk about experiments that are directly relevant to what you are about to describe. Fuller summaries of the literature are called review articles. and follow different conventions to an empirical report.
This requirement
may be fulfilled directly from the textbook or from information derived by
interviewing the trainer in an observational study.
Experiment
The method section will generally be rather dry and can be difficult to follow. Authors often use a paragraph or two prior to the Method to give a brief overview of what was done.
Such
introductory paragraphs are not required for Semester Project.
Method
The
Method section is the easiest section
to write because it is highly formalised. The whole thing is divided into
sub-sections. The only trick is to put the correct pieces of information in the
correct places.
Participants:
For the experiments run in Research Methods One, the following is sufficient:
How many people did you test in total? What was the source (e.g. Exeter
undergraduates)? What was the range of ages? Participants are what everyone
used to call "subjects", but political correctness required a change
of nomenclature.
This is
the place for a picture of your cat, significant other, or self.
Apparatus: (sometimes called
"Materials"): What major pieces of equipment were used in the
experiment? e.g.
The experiment was presented on a 14" colour monitor connected to an Acorn A5000 microcomputer. Responses were made via a standard PC keyboard. The monitor was placed at eye-level about 1 metre from the participants. Participants were tested in quiet cubicles.
This
is the place for pictures and/or drawings of your apparatus (food container,
bell, your kitchen, etc.).
Stimuli: This section is optional, but useful
if the items you present to the participants are complex and require
explanation. If you don’t have a stimulus section, the information it contains
should go in either the "apparatus" or the "procedure"
sections. Example extract from a stimulus section:
For each group there were 16 potential stimuli consisting of geometric forms mounted on plain white 12.7 x 20.3cm index cards. The forms varied along the four binary-valued dimensions of form, size, colour, and position. A form was either an equilateral triangle or a circle, either red or blue, had a diameter or height of 1.25 or 2.5cm, and was either singly or doubly represented on the card. Single forms were centered on the card. Eight cards were used for a given subject, and across subjects all 16 cards were used (Medin & Schwanenflugel, 1981, p. 358).
This
is the place for any pictures of complex stimuli (unlikely for semester
project).
Procedure: This
section should give a blow-by-blow, chronological, account of what happened
to the participant from the moment they started the experiment to the moment
they stopped producing analysable data. This includes both the preliminary
instructions, and the experiment itself. Procedure sections tend to be the
longest component of the Method.
Method sections are meant to be dull. Their purpose is to provide all the pedantic, detailed information that people will need if they are going to be able to replicate your experiment without assistance. Without this section, the knowledge contributed by the author is only verifiable while the author is both willing and able to provide detailed information.
Results
What
is, and is not, included in the Results sections
of reports is important. Result sections are like a witness’s statement - they
should include only verifiable facts.
They should not contain interpretation of those facts. They might summarise
what has been found only if there are many facts to be communicated.
Whether or not something is a fact is determined in many sciences by statistical methods. These methods use standard notation. So, result sections are littered with statements such as "F(14, 147) = 3.76, p < 0.05" or "t(12) = 30.21, p < 0.01".
Don’t
worry about statistical requirement for your report. Statistical analysis is
beyond the level of this course.
Do not include raw data, workings for statistical tests or, usually, justifications for the choice of test. The presumption is that the author is statistically competent. If there is reason for doubt, the readers can ask for the raw data, or run the experiment themselves. Such replication allows them to see whether they get the same sort of results. Always write full sentences; do not present results in note form.
This
section should contain figures and/or graphs showing experiment findings. This
section is also where the statement of success or failure to confirm the
experiment’s hypothesis is placed.
Results sections are dull. They are simply descriptions of the findings of importance, along with the (statistical) justification for accepting them as facts.
Discussion
The
Discussion section usually begins
with a summary of the main findings, and provides a compact description of their
implications. The section then continues with the implications in more detail
and, if appropriate, introduces alternative interpretations.
The agenda for the discussion was set by the introduction. The introduction
described what the questions and issues of the experiment were. 
The discussion section must address all the
questions and issues and address any effect the experiment had on them.
The last paragraph should be a strong finish that summarises the contributions
made by the study.
Discussion sections are what people remember. Assume your reader has been interested by your abstract, agrees with the assessment given in the introduction, and cannot find fault with the methodology, analysis, or the logic of your argument. If this is the case, then the report will be remembered as "the one that demonstrated X". The discussion section should set out, as clearly as possible, what X actually is.
Citing and Referencing
The information below is based on the 5th Edition of the Publication Manual of the American Psychological Association (APA). APA conventions are the standard for citations and references in Psychology. APA’s Publication Manual is occassionally updated. Recent changes include indenting of second lines and italics rather than underlining for journal title (or book title). Since Psychology 101 is not intended to teach report writing per se, only general adhearance to the guidence below is expected.
Reference Section or Bibliography
For
the Semester Project, the reference section should be very short. It should
contain, at a minimum the text book, the source you used for experimental
guidance, and, possibly, class notes. The only other material referenced should
be any sources you actually used to design, manage, or explain the experiment.
The reference section of a book review or essay should be an alphabetical list of all books and journal articles cited within the text. Journal articles and books are described differently but are combined in one reference list.
A Reference section for the semester Project should be minimal.
It should only include references actually used to perform the
experiment.
Conventions for an APA compliant reference section are as follows:
Citing Journal Articles
When a work has between two and six authors, cite all authors. When a work has more than six authors, list the first six authors, and use "et al." to signify the remaining authors. Examples:
Festinger, L., Riecken, H., & Schachter, S. (1956). When prophecy fails. Minneapolis: University of Minnesota Press.
Wolchik, S.A., West, S.G., Sandler, I.N., Tein, J., Coatsworth, D., Lengua, L., et al. (2000). An experimental evaluation of theory-based mother and mother-child programs for children of divorce. Journal of Consulting and Clinical Psychology, 68, 843-856.
The entry should begin with the last name of the first author, followed by his or her initials. Date of publication comes next, in brackets. The title should be italicised, but only the first word should be capitalised. Place of publication comes next, then the publisher. Use a colon after the place of publication. Each portion of the entry should be separated by a full stop and two spaces.
When a work is published by a corporation or institution, a typical reference entry should appear as follows:
Institute of Financial Education. (1982). Managing personal funds. Chicago: Midwestern Publishing.
Citing Books
A typical bibliography entry for a book will appear as follows:-
Arnheim, R. (1971). Art and visual perception. Berkeley, CA: University of California Press.
The book title should be in italics. Capitalise only the first word of the title (and the first word of the subtitle, if any) and any proper names. Include any additional information necessary for retrieving the book (such as "3rd ed." or "Vol. 4") in brackets, immediately after the title. End with a full stop.
End with publication information. Identify the city (or town) and, if the city is not well known or could be confused with another city, the state or county in the UK where the publisher is located. States should be named using their two-letter abbreviations in all caps (e.g. IL, VA, MD). Place a colon (:) after the city name, then identify the name of the publisher, clearly and briefly. Spell out the names of associations and university presses, but omit superfluous terms such as "Publishers," "Co.," or "Inc." If two or more locations are given, give the location listed first or the publisher's home office. Finish with a full stop.
To cite part of a source, indicate the chapter and notice that you should abbreviate the word chapter" in your citation:
(Hermione, 1983, chap. 3)
Chapters in a book
If you have read a chapter by Cox in a book by Broome & Llewelyn. In the text you would put the following: ( Cox 1995 ). Then in the reference section you would list Cox as below:
Cox, T. (1995). Stress, coping and physical health. In Broome, A. & Llewelyn, S. (eds). Health Psychology: Processes and Applications. (2nd edition). London: Chapman & Hall.
Citing Software
To cite computer software, a typical bibliography entry will appear as follows:-
Arend, Dominic N. (1993). Choices [Computer program]. Champaign, IL: U.S. Army Corps or Engineers Research Laboratory. (CERL Report No. CH7-22510)
The name(s) of the programmers are listed at the head of the entry, last names first, followed by a period. After listing the date in brackets followed by a period, italicise the title, and specify in square brackets that the source is a computer program. List the location and the organisation's name that produced the program. Add any other necessary information for identifying the program (in this example, the report number) in brackets at the entry's conclusion.
Citing Electronic References
Note: Some elements of the 5th edition's style guidelines for electronic resources differ from previously published guidelines.
Electronic sources include aggregated databases, online journals, Web sites or Web pages, newsgroups, Web- or e-mail-based discussion groups, and Web- or e-mail-based newsletters.
Online periodical:
Author, A. A., Author, B. B., & Author, C. C. (2000). Title of article. Title of Periodical, xx, xxxxxx. Retrieved month day, year, from source.
Online document:
Author, A. A. (2000). Title of work. Retrieved month day, year, from source.
Citations in the Main Text
Citing in text on the other hand is referring to author(s) with dates so that the reader can then go the References and find them in more detail. It’s sometimes known as ‘in-text citation’.
Basic format
(Author's Last Name, Year of Publication) . Eg. One recent study finds a genetic link to alcoholism (Jones, 1997). If the author’s last name appears in the citation, then only the year is required: i.e. Jones finds a genetic link to alcoholism (1997).
Multiple Authors
When a work has only two authors, use both of their names each time their work is cited, joined by an ampersand (&) if in brackets, or by the word "and" if in text:
in
brackets--(Cortez & Jones, 1997)
in
text--Cortez and Jones (1997)
For three, four, or five authors, refer to all authors the in the first citation, then use the first author’s last name followed by the abbreviation "et al." in all subsequent citations:
First
citation--(Cortez, Jones, Gold, & Hammond, 1998)
Subsequent
citations--(Cortez et al., 1998)
For six or more authors, use the first author's last name followed by the abbreviation et al.:
All
mentions--(Cortez et al., 1999)
Different Authors - Same Last Name
When citing different authors with the same last name, include their first and middle initials, so that a reader can differentiate between them:
(B.A.
Jones, 1998); (R.F. Jones, 1998)
Multiple Authors
Cited Together
The format for this type of citation is similar to that for citing more than one work by the same author (see above), except that semicolons are used to differentiate between authors:
(Jones,
1998; Heckels, 1996; Stolotsky, 1992)
Group Authors
When identifying group authors, use the same format as noted for single authors above, but substitute the company name. If the name is easy to abbreviate, then write out the full name in the first citation, and abbreviate it in all subsequent citations. If it is difficult to abbreviate, write out the full name each time:
First
citation--(National Institute of Mental Health [NIMH], 1999)
Subsequent
citation--(NIMH, 1999).
No Author Available
If no author is available, use a short form of the title (the shortest form that will allow you to recognise the work properly). For instance, if you were working with a study called "The Effects of Aspirin on Heart Attack Victims" you might use the following:
("The
Effects," 1995)
If you were working with an entire book with no author called Aspirin and Heart Attacks, you might use:
(Aspirin,
1991)
If the text is attributed to "Anonymous," then use the following format:
(Anonymous,
1999)
Specific Parts of a Source
(Asaki
& Klotzky, 1987. p. 333)
Personal
Communication
Personal communications receive a slightly more elaborate in-text citation, since they are not cited in the references section of an APA-style document:
(H.J.
Simpson, personal communication, September 29, 1999)
Secondary citations
If you are citing work from a secondary source, ie. where you have not read the original work, then the following practice should be adopted. Suppose you are commenting on the work of Brunswik (1939) which you have read about in Gordon (1996). In the text of the assignment put the following: (Brunswik, 1939, as cited in Gordon, 1996), or if Gordon gives no date for Brunswik, then put (Brunswik, as cited in Gordon, 1996). Then in the bibliography list only Gordon, as below.
Gordon,
I.E. (1996). Theories of Visual Perception (2nd edition). Chichester:Wiley.
More Information
(eg.
edited collections, dissertations etc) at
http://www.english.uiuc.edu/cws/wworkshop/bibliography/apa/apamenu.htm
Appendices
Some journal articles include appendices. If any you read do have them, examine what they contain. Generally it is information that, if included in the body of the article, would detract from the smooth flow of the argument. Typical examples are mathematical proofs, complex modelling, enumeration of extensive stimulus sets etc. Note that they do not contain raw data or workings for statistical tests. Neither should your lab reports (at least for Research Methods One). Your statistical calculations will need to be correct, but we don’t need to see your working. Your proficiency in following statistical methodology is tested by the statistics examination.
This
information last updated: 17/12/02http://www.ex.ac.uk/Psychology/handbooks/y1/labreports.html