Question

In the following situation, the sampling frame does not match the population, resulting in under coverage. Give examples of population members that might have been omitted.
The population consists of all 250 students in your large statistics class. You plan to obtain a simple random sample of 30 students by using the sampling frame of students present next Monday. (Select all that apply.)

--Students who are not taking statistics cannot be sampled.
--Students who are on a school trip cannot be sampled.
--Dropouts cannot be sampled.
--Students who are skipping class cannot be sampled.
--Home-schooled students cannot be sampled.
--Students who are out sick cannot be sampled.

Ok, I thought it was all of them because I believed it meant that anyone who would not be in the Stats class on Monday was out of the sampling frame. However, when I entered that, it was incorrect.

Answer 1

--Students who are not taking statistics cannot be sampled: these students do not represent and omission given the the population does not include students that are not taking statistics (" The population consists of all 250 students in your large statistics class")
 
--Students who are on a school trip cannot be sampled. This does represent an omission


--Dropouts cannot be sampled.

If the students droped then they are not in the class any more and you should not consider an omission. But this my be a criteria to clarify.


--Students who are skipping class cannot be sampled.

This indeed represents an omission

--Home-schooled students cannot be sampled.

This is not an omission because they are not part of the population.

--Students who are out sick cannot be sampled.

This indeed is an omission.