Muallagn

This research proposal from Psychology course 6461PIASTY at Universiteit Leiden investigates how second language fluency influences emotional expressiveness in bilinguals.

Practical R guide for course 6462PI004Y covering psychometric testing and scale development at Universiteit Leiden. Topics span four weeks: measuring and norming (z-scores, T-scores, percentiles), reliability assessment (split-half, Cronbach's alpha), validity and classification tables (confusion matrices, sensitivity, specificity), and construct validity through Principal Component Analysis. Includes executable R code examples and step-by-step procedures—essential for completing lab assign...

Study material for the Experimental Correlation Research course at Universiteit Leiden covering weeks 1-7 of the 2025/2026 academic year. The document includes worked examples and R code for correlations, simple linear regression, and multiple linear regression, with practical applications predicting school performance from motivation and intelligence. Ideal for understanding statistical testing, confidence intervals, and APA-style reporting of results—essential preparation for both coursework...