Data Analysis question...?

Question

so i have to analzye data from my experiment, the teacher asked us to find mean, median, mode, standard deviation q test etc. She also asked what our sample size was and if it was sufficient. I dont understand what she means by sample size, do i pick just any sample from my data?

Answer 1

Just means how many pieces of data did you collect. For example, if you are comparing people's heights and you measure 50 people, then the sample size is 50.

Answer 2

By sample size, your teacher is asking how many samples were taken. If, for example, you asked 100 people what their favorite color was, your sample size is 100. As another example, if you randomly selected 40 names from the phone book, your sample size would be 40. In short, it's how many samples were taken.

A sufficient sample size is one that reduces the error of having used too few samples to reach a conclusion. If you were asking people who the next president should be, would asking 10 people, or 10,000 people be a better indicator of how the population thinks? A larger sample size reduces the chance an error was made in reaching a conclusion. To calculate the error, there are statistical formulas all over the web to help you.

Answer 3

Yes and no. If you have 100 points in your entire data set, a sample would be a subset of those 100 points, consisting of anywhere from a single point to 99 points. The idea of picking a sample is that in real life, your entire data set might be unmanagably large (e.g. a country's entire population), so you pick a subset, a smaller number of points (people) that's easier to work with. But the sample has to be sufficient, i.e. large enough to be able to draw statistically valid conclusions about the entire data set. If the country's population was 10 million and you interviewed 100 people, that would hardly be large enough to be able to make any reasonable statements about the entire 10 million people, but interviewing 3 million people might be large enough. Another key feature which your teacher may have mentioned is your sample has to be representative. If 60% of the country is female and you interview 3 million males, your sample may be numerically sufficient, but by excluding females, it is hardly representative.

Answer 4

The question is asking you to sample size what this means is Select the data source and select Connect to a database then displays the actual sample size in the output along with the desired sample size

Answer 5

Sample size is the ammount of items studied.

For instance, 100 rocks, or 100 girls, age 18 only.