Identify the sampling technique used in each study. Explain yo...

Question

Identify the sampling technique used in each study. Explain your reasoning.

A study on attitudes about smoking is conducted at a college. The students are divided by class (freshman, sophomore, junior, and senior). Then a random sample is selected from each class and interviewed.

Accepted Answer

Hello there. Today we're gonna solve the following practice problem together. So, first off, let us read the problem and highlight all the key pieces of information that we need to use in order to solve this problem. A health researcher wants to study exercise habits among employees at a large company. Employees are first grouped by department such as HR, IT, marketing, and sales, and then a random sample is selected from each department. What type of sampling is this? Awesome. So it appears for this particular prompt we're asked to take all the information that is provided to us by the prom itself, and we're asked to determine what type of sampling is being performed for this particular case. So with that in mind, now that we know that we're ultimately trying to determine what type of sampling method is being used for this particular prom. Let's read off our multiple choice answers and see what our final answer might be. A is simple random sampling. B is stratified sampling. C is systematic sampling, and D is cluster sampling. Awesome. So first off, let us define each of our different types of sampling which are given to us by the multiple choice answers. So let us define the different types of sampling, which is gonna be for simple random sampling, stratified sampling, systematic sampling, and cluster sampling. So let's go and order and define each of those and provide an explan like a different type of example for each and when it is best used. So starting with simple random sampling, as we should recall, it's defined as every individual in the population has an equal chance of being selected. And an example, this particular type of sampling would be drawing names from a hat. And this particular type of sampling is best used when the population is small and hoogeneous, which is just a fancy way of saying the same and consistent throughout. And for stratified sampling, as we should recall, it's defined as the population is divided into subgroups, strata, based on shared characteristics such as age, gender, location. And a random sample is taken from each subgroup, and an example of stratified sampling would be sampling students from each grade level within a school. And this particular sampling method is best used when you want representation from all key subgroups. And as for systematic sampling, as we should recall, this is like defined as select every case item from a list or ordered population. After choosing a random starting point. So case to be particular. So it's like talking about like, you know, the 10th, 5th, 6th, etc. So taking, for example, like select every 10th item from a list or ordered population after choosing a random starting point, for example. And an example of this particular type of sample would be or sampling method, I should be specific, would be surveying, like we said before, every 10th person who enters a particular store, for example. And this particular sampling method is best used when the population is organized in a list in a fairly uniform fashion. And as for our last type of sampling listed, which is cluster sampling, we should recall that this is defined as the population is divided into clusters, often geographically, then entire clusters are randomly selected and all members. Of the selected clusters are surveyed, and an example, this particular sampling method would be selecting 3 neighborhoods randomly and then surveying all the households located within each neighborhood. And this particular sampling method is best used when the population is large and spread out geographically. So, switching gears now to focus our attention on our particular scenario that is given to us by the prom itself, we need to recall and note that the employees are divided into groups. And these groups are based on department, so I'll put a capital D for department in quotes. And as we know, the employees are divided into groups based on their department, such as HR, IT, marketing, and sales. We also need to note and recall that a random sample is taken from each department. And because a random sample is being taken from each department, we should be able to recognize at this point that this is a type of stratified random sampling, because the population is divided into strata and random sample. Or rather a random sample is being selected from each stratum. So that would mean, without a doubt, based on the information that's provided to us and all of our definitions for the different types of sampling, our final answer has to be multiple choice answer letter B, which once again is stratified sampling. Thank you so much for watching. Hopefully that helped, and I can't wait to see you in the next video. Bye.

Identify the sampling technique used in each study. Explain your reasoning.
A study on attitudes about smoking is conducted at a college. The students are divided by class (freshman, sophomore, junior, and senior). Then a random sample is selected from each class and interviewed.

Key Concepts

Stratified Sampling

Random Sampling

Sampling Bias

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