1
Q
Standard deviation for sample
A
s = sqrt(sum ( (X - M)^2) / (n - 1))
2
Q
Types of frequency tables
A
- Simple
- Relative (% of all scores). Proportion p= f/N
- Cumulative
3
Q
Linear interpolation for continuous variables
A
D1/W1 = D2/W2
Use real limits
