(a) Using Excel, find the mean, median, and mode for each quiz. Then also find the Range and Standard deviation(see supplemental notes for week 3).
Test 1 Test 2 Test 3 Test 4 60 65 66 10 60 65 67 49 60 65 70 70 60 65 71 80 71 70 72 85 73 74 72 88 74 79 74 90 75 79 74 93 88 79 95 97 99 79 99 98
(b) Do these measures of central tendency agree? Explain. What could the measures of dispersion tell us about the results of the quiz? We use descriptive statistics computations to allow us to describe data
Exercise 4-2
Confidence Interval
An experiment involves selecting a random sample of 256 middle managers. We would like to know the mean salary (annual income). The sample mean salary is 45,000, and the sample standard deviation is $2,000.
Calculate the 95% confidence interval, showing the confidence limits. Hint, because the sample size is greater than 30, we use the Z factor for 95%.
INCLUDE AN EXCEL SPREADSHEET SHOWING YOUR WORK TO CALCULATE THE 95% CONFIDENCE INTERVAL.