Table 7.7.a: Formulae for combining groups
|
Group 1 (e.g. males) |
Group 2 (e.g. females) |
Combined groups |
Sample size |
N1 |
N2 |
N1 + N2 |
Mean |
M1 |
M2 |
|
SD |
SD1 |
SD2 |
|