How to describe the theory or model in your IA Introduction

Travis DixonInternal Assessment (IB)

Your description of the theory in your IA should be clear, concise and correct. (Hopefully like this post).

Get everything you need for the IA right here.

Here I explain how to describe the theory or model in your IA Introduction for IB Psychology. WARNING: This post is only for those aiming for 7s. (Henceforth I will just say “theory” to make things easier but know that I mean theory or model)

There are three things I would recommend including to have a full description of your theory.

  1. The name of the theory and ideally also the theorist/s
  2. One or more important claims of the theory.
  3. How the theory explains the effect (IV->DV) you’re studying.

Remember you’re investigating the effects of some factor (the IV) on another (the DV). Therefore, you should be able to provide a theoretical explanation for this effect. This is what it means to “describe” the theory.

Pro Tip: Do some research beyond the textbook you’re using in class. Search and use original journal articles (at least one) and make sure to reference these properly in your description of the theory. This will ensure your description is accurate, referenced and not oversimplified.

As a teacher, I don’t explain this to my students before they attempt to write their first drafts. This post is written for those who have attempted it themselves and are struggling to figure out how to avoid a description that is still “….incomplete or contains errors” in their final draft.

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The following is an example taken from the IA in our IA support pack.

Example paragraph of a summary of a theory in an IB Psychology IA.

Note: This is presented as an example only. Feel free to break free from this model.

1. Name the Theory & Researcher/s

It’s not enough to write something like “memory theory” or “cognitive bias theory.” You must be specific. If your theory  doesn’t have a name, it won’t be recognizable to examiners. Here are some common theories relevant to the IA.

  • Schema theory
  • Dual processing model
  • The multi-store model
  • The working memory model

Are “effects” theories?

A theory could also be an effect, such as the misinformation effect, anchoring effect or Mozart effect. These are accepted in IB IAs as “theories or models.” However, if you’re aiming for a 7 I would recommend trying to find a theory that explains the effect. If you cannot, I recommend finding an original journal article that defines the effect and use this quotation (properly sourced) in your Introduction. Why? It (a) shows you have done some research and (b) ensures you define it correctly without oversimplifying.

Where do I find the theory relevant to my study? The best place to look is the introduction section of the original journal article of the study you’re replicating. The introductions are where the researchers will use a theory to explain the phenomenon (or the effect of the IV on the DV) that they’re investigating. If it’s not there, check the Discussion section of that same article.

Naming the researcher’s just helps ensure using an actual theory  and you’re properly referencing it. It might not always be the case that one researcher came up with the theory. For example, schema theory is the combination of contributions from a number of psychologists and many psychologists have proposed versions of the dual processing model.

2. Claim/s of the Theory

A “claim” is the theories explanation for something. Here are some examples of claims from famous theories:

  • Schema theory: “When new information becomes available a person tries to fit the new information into the pattern which he has used in the past to interpret information about the same situation.” (Alexrod, 1973, p.1248)
  • Dual processing model: “The notion that System 1 processes rapidly contextualize problems with prior knowledge and belief has been particularly emphasized in dual-process accounts of human reasoning.” (Evans, 2008, p.261)
  • Multi-store model: Information in the short-term store “…decays and is lost within a period of about 15-30 seconds.” (Atkinson and Shiffrin, 1968, p. 92)

Ideally the claim/s of the theory you state should be used to explain the phenomenon you’re studying and/or the results of the original study. This will make it easier to link the theory to your investigation.

3. Theory Explains the Effect

This final step does two things. First, it finishes off your “description” of the theory so it’s nice and detailed. Second, it is one way you can link the theory to your investigation.

Here are some theories that are used to explain effects. I have chosen theories probably not applicable to the IA so you’re not tempted to copy.

  • Social cognitive theory and the effects of TV on violence: Kids who watch violent TV might become violent through observational learning. If violent models on TV are rewarded for their behaviour in TV shows and movies, according to SCT it might further increase the likelihood that children will copy that behaviour.
  • Social identity theory and in-group bias: According to SIT, there is no need for direct competition for resources in order for people to show in-group bias. Simply becoming aware of an out-group is enough to cause individuals to demonstrate in-group bias.

These explanations of the effect will lead nicely into a summary of the original study that demonstrates the effect and thus those results can be explained by the theory.

The Rubric

These tips are designed to help you get your marker circling the 6/6 bracket.















Good luck.