Statistical testing

Question 1

Statistical testing

Answer 1

• provides a way of determining whether a hypothesis should be accepted or rejected
• shows if difference is significant or by chance

Question 2

Sign test

Definition

Answer 2

• a statistical test
• used to analyse the difference in scores between related items (e.g. the same participant tested twice)
• the data should be nominal

Question 3

Sign test

Conditions

Answer 3

• looking for a DIFFERENCE not an association
• used a REPEATED MEASURES design
• use data that is organised in categories (NOMINAL DATA)

Question 4

Sign test

Procedure

Answer 4

1) convert data into nominal data (categories) e.g. + or -
2) add up the categories e.g. + or –
3) S= less frequent sign
4) compare it with critical value
- calculated value must be EQUAL TO or LOWER THAN the critical value
- for results to be statistically significantly different

Question 5

Accepted level of probability in psychology

Answer 5

Accepted level of probability is 0.05 / 5%
P= 0.05
└that results occurred by chance
-more stringent significance level if human cost, or one off investigation (1%)

Question 6

Critical value

Answer 6

• for results to be significant

- calculated value must be EQUAL TO or LOWER THAN the critical value