IA Playbook
Frame your aim, design, and analysis so the investigation reads like one controlled study.
Use this guide to align your aim, theory, sampling, statistics, and evaluation with the IB psychology investigation criteria.
Psychology IA
See what each criterion measures, how many marks it carries, and what stronger evidence usually looks like.
Criterion names, marks, and mark bands follow the IB subject guide. The band descriptions are our own summaries, so check your subject guide for the exact wording.
How clearly you state the aim and its relevance, link your study to a theory or model, and write operationalized hypotheses.
Stronger evidence
The aim's relevance is explained, the theory is described and linked to your study, and the IV and DV are stated and operationalized in the hypothesis.
Early-stage evidence
The aim is stated without its relevance, the theory or model is incompletely or wrongly described, and the hypothesis misidentifies the IV or DV.
Whether you explain, not just describe, your design, sampling, participants, controlled variables, and materials.
Stronger evidence
The design, sampling technique, choice of participants, controlled variables, and choice of materials are explained.
Early-stage evidence
The design, sampling technique, participants, controlled variables, and materials are described.
How accurately you apply descriptive and inferential statistics, graph the results, and interpret the findings.
Stronger evidence
Correct descriptive and inferential statistics, a correct graph that addresses the hypothesis, and findings interpreted and linked to the hypothesis.
Early-stage evidence
Only descriptive or only inferential statistics; the graph type is right but does not address the hypothesis; findings are not clearly stated.
How well you discuss findings against the theory, evaluate your design, and justify modifications.
Stronger evidence
Findings are discussed with reference to the theory, relevant strengths and limitations are explained, and modifications are tied to your limitations and justified.
Early-stage evidence
Findings are described without reference to the theory, strengths and limitations are stated but not relevant to the hypothesis, and modifications are stated.
| Marks | What the draft currently shows |
|---|---|
| 0 | Nothing in the work reaches the lowest band. |
| 1-2 | The aim is stated without its relevance, the theory or model is incompletely or wrongly described, and the hypothesis misidentifies the IV or DV. |
| 3-4 | The aim's relevance is identified but not explained, the theory is described without linking it to your study, and the IV and DV are correct in the hypothesis but not operationalized. |
| 5-6 | The aim's relevance is explained, the theory is described and linked to your study, and the IV and DV are stated and operationalized in the hypothesis. |
| Marks | What the draft currently shows |
|---|---|
| 0 | Nothing in the work reaches the lowest band. |
| 1-2 | The design, sampling technique, participants, controlled variables, and materials are described. |
| 3-4 | The design, sampling technique, choice of participants, controlled variables, and choice of materials are explained. |
| Marks | What the draft currently shows |
|---|---|
| 0 | Nothing in the work reaches the lowest band. |
| 1-2 | Only descriptive or only inferential statistics; the graph type is right but does not address the hypothesis; findings are not clearly stated. |
| 3-4 | Suitable descriptive and inferential statistics with errors; the graph addresses the hypothesis but has errors; findings are stated but not interpreted or not linked to the hypothesis. |
| 5-6 | Correct descriptive and inferential statistics, a correct graph that addresses the hypothesis, and findings interpreted and linked to the hypothesis. |
| Marks | What the draft currently shows |
|---|---|
| 0 | Nothing in the work reaches the lowest band. |
| 1-2 | Findings are described without reference to the theory, strengths and limitations are stated but not relevant to the hypothesis, and modifications are stated. |
| 3-4 | Findings are described with reference to the theory, relevant strengths and limitations are described, and modifications are described but not tied to your study's limitations. |
| 5-6 | Findings are discussed with reference to the theory, relevant strengths and limitations are explained, and modifications are tied to your limitations and justified. |
Did You Know? Most weak drafts fail from sequence chaos, not lack of ideas.
Step 1
Make the theoretical basis, variables, and operationalized hypothesis explicit before moving into the method.
Step 2
Justify the sampling, participants, controls, and materials instead of listing them without context.
Step 3
Choose statistics and graphs that actually answer the hypothesis and make the findings easy to follow.
Step 4
Link each limitation and proposed modification directly to the hypothesis and observed findings.
Did You Know?
Marksy grades your report against IB criteria, flags missing operational definitions, and helps you tighten the link between statistics and conclusions. The result includes an estimated mark for every criterion, evidence from your draft, and the changes to make first. Your final mark may differ after teacher assessment or external moderation.
Instant Grading Results
See where your score is now, not just where it could be.
Criterion-By-Criterion Feedback
See the estimated mark, evidence, and next step for every assessment criterion.
Action List To Improve
Get concrete next edits instead of vague "improve analysis" advice.
Confidence And Integrity Signals
Review flagged sections and strengthen authenticity before submission.