Question

Which of the following scenarios represent random sampling without replacement? (I) We visit a farmer's market and ask a vendor for three apples from a crate. The vendor picks three apples and gives them to us. (II) Each student in a class rolls a die. Those students who get a 6 are selected to complete a special survey. (III) Each day at a hospital, ten patients are randomly selected from all patients who had an appointment that day. This study is completed over 2 years to help ensure patients with a large number of ailments are considered (including seasonal ailments, like influenza). I only

II only

I and II

II and III

I, II, and III

None of the above Incorrect

Answer 1

In a random sample, there is no criteria for selection of a sample and hence, the samples are randomly selected with each individual member of the population having equal chance of getting selected. A sample is with replacement is available for selection on all trials and is without replacement if an individual once selected cannot be selected again for the sample.

I) Random sample without replacement.

II) Random sample with replacement (it's possible two students to get same outcome)

III) Cluster sample

Ans: I only