A researcher wants to obtain a random sample of the 800 cows from a local farm. He decides to ask the farmer to give him the ear tag numbers of 100 cows he can use in his study. The researcher puts these tag numbers into a hat and randomly chooses 40 to include in his study.

Your question is?

Indicate which of the following sampling techniques are examples of random sampling. For those that are not examples of random sampling, explain why.

What do you think?

I think that it is a random sample.. however the wording is confusing me.. help please?

I don't think it's random because the farmer chose the 100 cows.

yeah.. but then 40 others were chosen??

Why do well crafted Small-N research designs have such high internal validity?