Data Science and Analytics IV-1 new.pptx

Inferential statistics

1. F-test – ANOVA – Two-factor experiments – three f-tests – two-factor ANOVA –Introduction to chi-square tests.. 1

2. Example Data

3. F table In this case, the column with 2 degrees of freedom and the row with 6 degrees of freedom intersect a cell (shaded) that lists a critical F value of 5.14 for a hypothesis test at the .05 level of significance. Because the observed F of 7.36 exceeds this critical F , the overall null hypothesis can be rejected

4. Computations

5. Computations

6. Formula for degrees of Freedom

7. Computations

8. Formula

9. Formula Where X = raw score T = group total n = group sample size G = grand total N = grand (combined) sample size

10. Formula

11. F table In this case, the column with 2 degrees of freedom and the row with 6 degrees of freedom intersect a cell (shaded) that lists a critical F value of 5.14 for a hypothesis test at the .05 level of significance. Because the observed F of 7.36 exceeds this critical F , the overall null hypothesis can be rejected