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Finding Appropriate Sample Sizes

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Are there any steps I can take to ensure that I have an appropriate sample size? How can I make sure that even with appropriate numbers that the distribution of the sample is representative? Are there tests that I can run that will assist with this and or any strategies for ensuring my sample coverage and variability?

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Hi, my name is Jamie and I'd like to help you with this question. I am finishing my PhD in Psychology and I have a lot of experience with research methods.

First of all, you want to make sure that your sample is a good representation of the overall population you are interested in studying. The sample is the group of individuals actually participating in the study. It is necessary to ensure that your sample is a good representation of your population of interest, so that you can draw inferences and make valid and reliable conclusions.

To obtain a solid sample from the population you want to study, it might be a good idea to obtain the data from questionnaires, self-reports, peer feedback, etc. Obtaining rating scales, behavior reports or other types of assessment questionnaires is going to be very helpful for you. To conduct a study on human subjects, your proposal must pass what is called the IRB: Institutional Review Board. Most colleges and universities have their own IRBs, so check with your professor or Principal Investigator for more information. I am including the note on the IRB here, as it is one of the most important steps in obtaining the proper sample for your study.

One of the most important ways to assure your sample is representative of the population you are studying is to employ random sampling. This means that members from a specific ...

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The expert finds the appropriate sample sizes for the strategies ensuring a sample coverage and variability.

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