Here is the scenario: Let's say that two sets of samples (SET 1 and SET 2) are from the same population (N=1000). SET 1 and SET 2 has the same sample size (n=500). SET 1 is composed of doctors only, and their average (mean) price that they are willing to pay for a certain product (a new drug) is $20. While SET 2 is composed of doctors, nurses, patients, etc, and their average (mean) price that they are willing to pay for a certain drug is $40.(adsbygoogle = window.adsbygoogle || []).push({});

My questions are the following:

1.How can I test if there is a difference between two sample means from SAME population?

2. If I run another survey for NURSES only, with the same sample size (n=500), will I get a sample mean price lower than the sample mean price of SET 2 (which is $40)?

3. Does the sample mean of SET 1, which is just a subset of SET 2 in terms of composition, is always lower than the sample mean of SET 2?

Thank you very much

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# How can I test the difference between two sample means from SAME population?

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