Statistical Testing (AQA A-Level Psychology): Flashcards

Purpose of statistical testing in psychology

Determines if findings are genuine effects or occurred by chance

What the sign test examines

Differences in scores when same participants tested twice

Psychology's accepted significance level

0.05 (5%)

Definition of critical value

Threshold that must be reached for statistical significance

Three requirements for using the sign test

1. Looking for differences 2. Repeated measures 3. Nominal data

Calculated value S in sign test

The smaller of the two totals (positive or negative signs)

When sign test results are significant

When S is equal to or less than the critical value

What nominal data means

Data organised into categories

Information needed to find critical value for sign test

1. Significance level 2. N value 3. One-tailed or two-tailed

What a significant difference means

Results unlikely to have occurred purely by chance