Introduction to T-test

Introduction to T-test

1. We are looking for differences

2. Interval and ratio

3. Independent groups

4. parametric

5. What is a T-test? A test that compares 2 means, a test that involves 2 groups of (one group and population) and looks at differences between 2 groups

6. There are two types of t-test

   • unrelated./independent/between groups
     • e.g. Is there a difference male and female scores on a numerical ability test?
   • related/dependent/paired samples
     • e.g does recall improve after attending 'Hypnotic Memory Training with Paul McKenna?'

7. t-test basically relate the difference between our means to the above sampling distribution

8. The associated probability tells us whether or not our diffference mean falls within the most extremme 5% of difference mens that could be expoected

9. spss generates a -statistic - t basically tells us how many standard deviations our difference is from zero in the middle of the theoretical distribution

10. one sample t-test compares your sample with your known population

    • when we know the mean of the population

11. To report a one sample T-test in APA format you need to know the df, t -value and p-value

    • t(df)= t-value, p=p-value