IB Psychology HL Internal Assessment Example

The student’s investigation aim is clearly and concisely stated, establishing a solid foundation for the study by linking facial symmetry and attractiveness within evolutionary psychology.

While the Rhodes et al. description is accurate, the link to the current hypothesis is asserted without critical analysis; strengthen by discussing how that manipulation informs your design.

Consider elaborating on the ‘good genes’ hypothesis and developmental stability mechanism to clarify why symmetry signals genetic fitness in the present study.

The use of a non‐scholarly website for the 2% symmetry statistic undermines credibility; replace with peer‐reviewed data to strengthen theoretical grounding.

The dependent variable description conflates attractiveness and symmetry ratings and quotes phrasing loosely; operationalise solely attractiveness on a 1–5 scale.

The independent variable is well specified, facilitating replication by distinguishing symmetrical versus asymmetrical faces.

Controlled variables are listed but their influence on internal validity is not explained; clarify why uniform expressions and image quality reduce confounds.

The mixed stratified–convenience sampling description is confusing; justify why equal gender representation and non‐psychology students yield a representative sample.

Materials are identified but lack rationale; explain why a quiet area and digital photographs are essential for reducing distractions and standardising stimuli.

The methodology text repeats that both conditions were “symmetrical faces” twice, indicating a copy–paste error; correct to asymmetrical for the control group.

No explicit check of distribution or homogeneity of variance is reported prior to conducting the Mann–Whitney U test; include assumption verification.

The definition of mean in the analysis is overly elementary and distracts from the core data interpretation; focus on statistical reasoning instead.

The bar chart omits error bars or confidence intervals, reducing interpretative clarity; include them to illustrate variability.

Report an effect size (e.g., r or η²) alongside the U‐test to quantify the magnitude of the symmetry effect.

The means and standard deviations table is correctly formatted, offering clear descriptive insight into each condition.

The U‐test interpretation is otherwise correct and directly linked to the hypothesis, demonstrating appropriate inferential reasoning.

The description of the Mann–Whitney U test as comparing sample means is inaccurate; clarify it compares rank distributions or medians.

Including the full Mann–Whitney U calculation in an appendix shows transparency, but summarize the key U and p‐value in the main Results section.

The detailed skewness and normality outputs demonstrate rigorous assumption checking, enhancing the credibility of the inferential analysis.

The evaluation discussion references only Rhodes et al.; broaden to include contradictory findings or alternative models for critical depth.

Strength and limitation statements are relevant but would benefit from quantifying how much partial awareness or editing transparency influenced validity.

The proposed cover story and software upgrade address limitations clearly and show thoughtful investigation improvement.