Is it an SRS? A corporation employs 2000male and 500 female engineers. A stratified random sample of 200 male and 50 female engineers gives each engineer 1 chance in 10 to be chosen. This sample design gives every individual in the population the same chance to be chosen for the sample. Is it an SRS? Explain your answer.

Short Answer

Expert verified

We are only interested in 200 male and 50 female engineers, some samples of size 250 are less likely to be selected. There is no chance of a sample of 250 females or 250 males being selected.

Step by step solution

01

Given information

No. of male engineers = 2000

No. of female engineers =500

Sample size of male engineers =200

Sample size of female engineers =50

02

Concept

A simple random sample (SRS) of size n is made up of npeople chosen from the population with an equal chance of being the sample that is actually chosen.

03

Explanation

Every person in the population has the same chance as the selected sample of 200 male and 50 female engineers. An SRS ensures that any sample of a given size has the same chance of being chosen. It is not an SRS since the selected sample of 200 male and 50 female engineers offers each individual in the population the same chance, but it does not give every conceivable sample of 250 engineers the same chance. Because we are only interested in 200 male and 50 female engineers, some samples of size 250 have a lower chance of being chosen. A sample of 250 females or 250 males has no chance of being chosen.

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