Suppose your data set contains ages (in years) and you calculate ...

[karen]

Suppose your data set contains ages (in years) and you calculate the range, variance, standard deviation, and coefficient of variation for the data. Explain what units each of these measures is in.

Question 2

In testing the null hypothesis H0: The process is in control, explain the difference between a Type I error and Type II error.

[cuttiesgirl16]

Answer to Question 1

Range subtracts two years (largest minus smallest) so it is still in units of years. The variance is the average squared deviation from the mean, which is measured in square units. In this case, years squared. (These units have no meaning in this case.) The standard deviation is the square root of the variance, taking the units back to years. The coefficient of variation takes the standard deviation (in years) divided by the mean (in years) and hence has no units at all.

Answer to Question 2

A Type I error is rejecting a true null hypothesis; therefore, a Type I error in this situation will result in a belief that the process is not in control when it really is. A Type II error is failing to reject a false null hypothesis; therefore, a Type II error in this situation will result in a belief that the process is in control when it really is not.

[karen]

Thank you!

[cuttiesgirl16]

Always glad to help...