Question

# There is a hypothesis that folate deficiency during pregnancy may harm the ferus To study this...

There is a hypothesis that folate deficiency during pregnancy may harm the ferus To study this phenomenon, 10 pregnant mice are fed a diet deficient in folate When each mouse gives birth, the birthweight of each pup (baby mouse) will be measured. Suppose the mice give birth to a total of 85 pups, so that the experimenter has 85 observations of Y - birthweight To calculate the standard error of the mean of these 85 observations, the experimenter could calculate the standard deviation of the 85 observations and divide by the square-root of 85 On what grounds might an objection be raised to this method of calculating the SE?

The standard error of the mean is usually estimated as the sample standard deviation divided by the square root of the sample size (assuming statistical independence of the values in the sample). n is the size (number of observations) of the sample.

Here the sample size could be the objection as 10 mice have give birth to these 85 pups. Hence divide by square root 85 can raise objection because 85 pups have been given birth by 10 different mice and not single mice. Standard error would also have to considered this factor.