# Samples and populations

Is the sample a part of the population or the population apart of the sample? Why would researchers just not use the entire population to be more accurate? Can you give an example of a sample from a given population?

What do you need to be mindful of regarding your sample that will affect your results? What is a random sample? What are methods and types of random samples? When might you not want to use a random sample? Is it possible to generalize your findings with out a random sample? Does the composition of your sample determine if it is random? If not, how is this determined?

What is the difference between the population and the target population?

What things can limit a survey researcher's ability to draw valid inference from the sample to the population?

What other factors should you consider when defining your population and your sample?

If your sample is freshmen in college that voluntarily participated in a psychology research study, what population can you generalize to with your research findings?

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Is the sample a part of the population or the population apart of the sample? Why would researchers just not use the entire population to be more accurate? Can you give an example of a sample from a given population?

- A sample is part of a population. How you have to look at it is like this: the population consists of EVERYONE that falls under a category. For example, if you are looking at university students, the population would be every university student. Now if you want to do research on university students, it would be very expensive and long to include everyone in the population of students. Therefore, we would have a sample of students - for example, all of the students in one university, or all of the students in one class in a university. This way we can conduct our research with a more manageable number of participants.

What do you need to be mindful of regarding your sample that will affect your results? What is a random sample? What are methods and types of random samples? When might you not want to use a random sample? Is it possible to generalize your findings with out a random sample? Does the composition of your sample determine if it is random? If not, how is this determined?

- When having a sample, we have to make sure that the sample is an accurate representation of your population. In other words when you have a sample, you want to assume that this sample is representative of the general population. First thing is that we ...

#### Solution Summary

This posting looks at many aspects related to samples and populations, and describes important aspects such as:

- the need to have a random sample

- if you can make inferences on your population based on your sample

- how to generalize your results from your sample to a population