sampling, variables, hypothesis testing, z scores, and standard deviation

Expert Solution

Sampling is a process used in statistical analysis in which a predetermined number of observations are taken from a larger population.

A variable is any characteristics, number, or quantity that can be measured or counted.

A statistical hypothesis is an assumption about a population parameter. This assumption may or may not be true. Hypothesis testing refers to the formal procedures used by statisticians to accept or reject statistical hypotheses.

To find the Z score of a sample, you'll need to find the mean, variance and standard deviation of the sample. To calculate the z-score, you will find the difference between a value in the sample and the mean, and divide it by the standard deviation.

Standard deviation is a number used to tell how measurements for a group are spread out from the average (mean), or expected value. A low standard deviation means that most of the numbers are close to the average. A high standard deviation means that the numbers are more spread out.

milcah answered 1 year ago

CHAPTER 10: INTRODUCTION TO HYPOTHESIS TESTING: The z Test Key Terms Sampling distribution of z ---...

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