Statistics: Inferential & Descriptive (OCR A-Level Psychology): Flashcards

Range of correlation coefficient (r)

-1 to +1

r = +1 represents

Positive correlation

r = -1 represents

Negative correlation

r closer to 0 means

Weaker relationship

r closer to -1 or +1 means

Stronger relationship

Inferential statistics purpose

Test if results are statistically significant

3 factors choosing statistical test

1. Difference or correlation 2. Experimental design 3. Level of measurement

Test: repeated measures + ordinal

Wilcoxon Test

Test: independent groups + ordinal

Mann-Whitney U Test

Test: correlations + ordinal

Spearman Rho Test

Nominal data definition

Data in categories

Ordinal data key feature

Ordered but lacks equal intervals

Interval data key feature

Equal, precisely defined units

Data type needed for parametric tests

Interval data

Test: repeated measures + interval

Related T Test