Question

type your answer in exactly as one of the following: population, sample, srs, systematic, stratified, cluster, multistage, voluntary, convenience, survey, observation, experiment, undercoverage, response, nonresponse
(answer the multiple choice with a uppercase letter)

1. source of bias that occurs when an individual chosen for the sample cant be contacted or refuses to cooperate.

1. an srs of 25 students is taken from each grade to form the sample. this is what type of sampling design?

Explanation:

Step1: Identify bias type

Nonresponse bias arises when selected individuals can't be contacted or refuse to cooperate.

Step2: Identify sampling design

Stratified sampling divides the population into groups (grades here) and samples from each group.

Answer:

nonresponse
stratified