Question

Statistics sampling concept

1. we sample 7groups from the population and each group has n=10,then we calculate the mean for each group . Finally, we use the mean of each group to calculate the mean . The mean should be closed to the population mean

2. we only sample one group but the n is large so the mean of that group would be close to population mean as well

my question is when I should apply the first method and when I should apply the second one

also, what the difference is between these two L

when we say something about sampling distribution are we talking about 1or 2?

follow the comments please

Answer 1

Answer:-

(1) As we know that from the property of good samples , we should take a sample which is representative of whole population.When there is heterogeneity in the population taking a single large sample gives you ambiguous result that's why we sample 7groups from the population and each group has n=10,then we calculate the mean for each group . Finally, we use the mean of each group to calculate the mean.

(2) When our population is homogeneous and normally distributed taking a single large sample be a good representative of whole population , that's why we only sample one group but the n is large so the mean of that group would be close to population mean as well.

That is, it depends upon nature of your population (heterogeneous or homogeneous) that is we take samples by first or second method.