Answer :
Answer:
I you want to ensure that you could detect a mean change of 0.03 units with a probability of 0.8, then you need at least 40 individuals for the sample.
Step-by-step explanation:
Minimum required sample size can be found using the formula
N≥[tex](\frac{z*s}{ME} )^2[/tex] where
- N is the sample size
- z is the corresponding z-score for (0.8 probability) 80% confidence level (1.28)
- s is the standard deviation (0.148)
- ME (margin of error) is the margin for detecting mean change (0.03)
Using the numbers we get:
N≥[tex](\frac{1.28*1.48}{0.03} )^2[/tex] ≈ 40