IB Psychology IA Guide: HL


Why does the IA matter?

The Internal Assessment (IA) is a critical, but very doable, part of IB Psychology. You cannot pass IB Psychology without completing it. The IA is worth 25% of the grade for SL and 20% for HL.

Before you freak out or give up (depending on the student), we want to let you know that it’s actually a fun and interesting experience. It’s kind of like baking cookies: if you follow the instructions step by step, you’ll end up with great results; but if you leave out ingredients (like sugar) or add unnecessary ones (like sardines), it may not be as pleasant.


So what is the IA?

The IA is simply a replication of a published study. In other words, you’re going to find a study that was already done and go out into the world, do it yourself, and write up what you did. However, HL students have the option of modifying the original study. For example, if the study uses a car crash as a means to test memory construction, you may choose to use a fight or a dance instead. Either way, there are a few rules you have to follow:

ü  Does not cause participants harm or distress,

ü  Does not use young children (anyone under 18 must receive parental permission through a consent form),

ü  Debriefs participants afterwards and gives them the right to withdraw their own personal data and responses, and


ü  Guarantees anonymity for each participant.




Which studies can you replicate?


Technically, you can choose any study you want (so long as it only manipulates ONE independent variable), but we strongly advise you to choose one of the following options:





Original Study

Chartrand and Bargh, “The Chameleon Effect as Social Glue: Evidence for the Evolutionary Significance of Nonconscious Mimicry,” 1999.



To investigate the occurrence of a chameleon effect in an interview situation


Independent Variable (IV)

Presence/absence of foot-tapping and face-rubbing mannerisms in interviewer (condition 1: interviewer exhibits foot-tapping and face rubbing mannerisms; condition 2: interviewer does not exhibit foot-tapping and face-rubbing mannerisms)


Dependent Variable (DV)

Frequency of foot-tapping and face-rubbing mannerisms in participants/interviewees


Research Hypothesis

The frequency of participants’/interviewees’ foot-tapping and face-rubbing mannerisms will be greater when with an interviewer who taps their foot and rubs their face than with an interviewer who does not demonstrate these behaviors.






Original Study

Triplett, The Dynamogenic Factors in Pace-Making and Competition,” 1898.


Triplett Explained in simple terms



To investigate the effect of co-actors on competitive performance of a task


Independent Variable (IV)

The presence/absence of co-actors (condition 1: co-actors present; condition 2: co-actors absent)


Dependent Variable (DV)

Time taken to reel in fishing line through a 4 m course


Research Hypothesis

The time taken to reel in fishing line through a 4 m course is reduced by the presence of co-actors.







Original Study

Loftus, E.F. and Palmer, J.C. “Reconstruction of Automobile Destruction; An example of the interaction between language and memory,” Journal of Verbal Learning and Verbal Behavior, no. 13, pp. 585-589, 1974.



To investigate how information supplied after an event influences a witness’s memory for that event


Independent Variable (IV)

The verb used to describe an automobile accident


Dependent Variable (DV)

The speed estimate given


Research Hypothesis

The speed estimate will change according to the verb given









Original Study

Loftus, E.F. and Zanni, G. “Eyewitness Testimony: The influence of the wording of a question.” Bulletin of the Psychonomic Society, Vol. 5 (1), 86-88, 1975.



To investigate whether the changing the wording of a questions alters a person's memory reconstruction.


Independent Variable (IV)

The indefinite or definite article used in the question


Dependent Variable (DV)

The recollection of the broken headlight


Research Hypothesis

Changing an indefinite article (“a”) to a definite article (“the”) in a sentence will decrease the “I don't know” responses when asked about a broken headlight in an accident.







What does the IA look like?


Here’s an outline…

Title page

·         Title

·         Student name and number

·         Subject and level

·         Date, month and year of submission

·         Number of words

Table of Contents

·         List of parts and pages


·         Statement of aim

·         Summary of methods

·         Summary of results

·         Conclusion


·         Aim of the study

  • Literature review (analysis of relevant background studies and theories)
  • Operationalized experimental hypothesis

·         Operationalized null hypothesis


(sub-section headings are in bold)

  • Design: type and justification of experimental design, controls, ethical considerations including informed consent, identification of independent and dependent variables
  • Participants: characteristics of sample, sampling technique, allocation of participants to conditions
  • Materials: list of materials used, reference to copies in appendices
  • Procedures: described in sufficient detail to allow full replication


  • Statement of the measure(s) of central tendency, as appropriate
  • Statement of the measure(s) of dispersion, as appropriate
  • Justification of choice of descriptive statistic
  • Reporting of inferential statistics and justification for their use (calculations in appendix)
  • Statement of statistical significance
  • Appropriate use of fully explained graphs and tables (may be computer-generated)


  • Interpretation of descriptive and inferential statistics
  • Comparison of findings to studies and theories reviewed in the introduction
  • Identification of limitations of the student’s research
  • Suggestions for modification to address limitations of the student’s research
  • Conclusion


  • Works cited within the report listed in a standard format



1. Title Page

This page should have your title in the top center of the page.

In the bottom left corner, you should put your:

            1. Name

            2. IB ID number (ask us and we will provide it)

            3. Subject (IB Psychology HL or SL)

            4. Month and year of submission (March 2016)

            5. Word Count (1000-1500 words), which does NOT include the title page, abstract, references, or appendices


2. Abstract

This is a summary of your whole IA. You CANNOT write this until you have finished the IA in its entirety. The reader should understand the basis of the whole experiment from your abstract. You should start out by identifying the study you’re replicating, state your aim (“to investigate X”), write two to three sentences on how you went about the study, state the results (give the actual numbers that you found), and note what you concluded from the study. The whole abstract should not be more than 200 words. Give the word count for the abstract below the abstract itself. The abstract (and its word count) should be the only thing on the page.



For the abstract and the entire IA, you must:


3. Table of Contents


4. Introduction

The introduction should be about 600 words, and include background theory and research which logically leads into the aim and hypothesis of your study.

Discuss your topic area in context: Start off by identifying the particular aspect of the discipline of psychology in which your study takes place (e.g., memory reconstruction in the cognitive level of analysis, social facilitation in the sociocultural level, etc.). BRIEFLY explain the nature of this area of psychology; what is the cognitive level of analysis really about? Define this area of psychology, if necessary.

Next, talk about the particular topic that your study addressed, such as memory.

Review the background material relevant to your study: This is NOT an exhaustive list of all the research available. Include two or three studies that directly relate to your research question.  You will refer to these studies again in the Discussion section.

Outline the precise problem you chose to investigate and describe the way you went about investigating it: Give clear justification as to why your topic is important to study. Give your reader the general idea of how you went about doing your study.

Outline the results predicted by your research hypothesis: What did you think would happen? Clarify WHY and HOW your study tested this.

State your research (H1) and null (H0) hypotheses.

You do NOT need to put the introduction on a separate page from the sections that follow. The rest of the paper can share pages until you get to the reference page.




5. Method

The methods section is meant to tell the reader HOW you went about actually doing your experiment. It’s broken down into 4 subsections:

·         Design:  Did you use independent or repeated measures in your experiment? Why did you use this design? How did it help research the aim of your experiment? How did the design help you control for confounding variables? Was it a single- or double-blind study? What steps did you take to make sure the experiment was ethical? Finally, clearly state the operationalized independent and dependent Variables.

·         Participants: How did you find your sample? Was it an opportunity sample, random, snowball? Justify why you used that type of sampling. Include the size of the sample (a participant sample of 20 is recommended) and information on how the participants were selected and assigned to experimental conditions (that is, explain how you put them into the experimental and control groups)

·         Materials: What physical materials did you use in your experiment? This can include any standardized instructions, informed consent forms, tests, word lists, debriefing notes, etc. The list can be bulleted, and you’ll need to attach the actual forms in the appendix.

·         Procedures: How did you actually go about doing the experiment? In paragraph form, state step by step how you read the debriefing script, handed out your materials, and debriefed the participants.


6. Results

State your findings in this section. As an HL student, you will present TWO types of results: descriptive and inferential

Descriptive results just describe where the middle of your data is (e.g., mean, median, range, or standard deviation). When writing the descriptive section, you should start out with a table that compares your two groups using mean, range, and/or standard deviation. Next, present your data in a bar graph comparing the two groups (not individual results). Make sure the graphs are clearly and specifically labeled. 

You will then write a paragraph that includes the following:

• Statement of the measure(s) of central tendency, as appropriate

• Statement of the measure(s) of dispersion, as appropriate

• Justification of choice of descriptive statistic

You should give a narrative presentation of the results related to the aim and hypotheses of the experiment.

Inferential statistics enable us to draw conclusions about the likelihood of the hypothesis being accepted. There are different tests you can use depending on what type of data you collected.  Before you pick a test, you must know whether your data is nominal or ordinal. Nominal data is where you assign a number to a condition (like “blue equals 1” and “brown equals 2”). Ordinal data is when the data can be ranked or given a rating scale (e.g., when rating Mr. Gino’s attractiveness, you give him a 1 for “homely,” a 2 for “normal,” and a 3 for “gorgeous”).

In general, consult the following explanations to decide which test to use.

·         The Chi Square test is used for nominal data in an independent samples design when the experiment tests a difference between two conditions.

·         The Mann-Whitney U test is used for ordinal data in an independent samples design when the experiment tests a difference between two conditions.

·         The Wilcoxon Signed-Rank test is used for ordinal data in a repeated measures design when the experiment tests a difference between two conditions.

Once you do your test, you’ll look up the critical value of your results and state its p value. If p is less than or equal to .05, you’ll reject the null hypothesis. If it’s higher than .05, you’ll reject the experimental hypothesis. Present this information in a short paragraph at the end of the Results section.

You should include the actual work for the tests in an appendix, presented in a readable form with all headings clearly explained. Don’t include personal details, such as the participants’ names, which are confidential. Don’t include the participants’ actual answer sheets, either.


7. Discussion

This section is worth the most points, so give this the most attention.

The discussion should address 4 ideas:

1. Explanation of findings: The word, “explain,” means to give a detailed account, including reasons or causes. (Explanations should include reference to descriptive and inferential statistics.) In other words, why did you get the results that you got?

2. Relationship to background research: This is your opportunity to explain your results in relation to the study you replicated. No new research should be included here, and avoid repeating material from the intro. Did your work support or contradict the original study’s findings?

3. Limitations, modifications, and suggestions for further research: Even a well-designed study will have flaws. You should note your own experimental flaws and problems that may have affected the results, such as lack of sampling controls and problems with the procedure, materials, and design. Next, suggest modifications that would avoid these problems. Modifications need to be clearly stated and could include other ways of investigating the aim. Avoid obvious suggestions like “testing more people.” Refer to any ideas you have for further or follow-up research.

4. Conclusion: You should finish with a brief, focused summing up of your findings, relating back to the aim and hypotheses.


7. References

This section should be a list of all the material you’ve referred to in the Introduction and Discussion sections of the IA.

References should follow a recognized format and be consistent throughout. The recommended style is MLA or APA.

If you don’t have the original source material, you can find all the necessary details in the “References” section at the back of the book that referred to the source.


8. Appendices

This should be where you attach everything you referred to in the Materials and Results sections.  Examples are: