Question

Use the following information to answer Questions 1 through 3
The manager of OfficeSpace Inc. wishes to determine whether employees with an office spend more or less “down time” on the computer than employees working in a cubicle. She tracks the monitors of 7 cubicle-workers (denoted as X) and 3 office-workers for 8 hours each. She finds that the cubicle-workers spend an average of 38 minutes of “down time,” and the office-workers spend an average of 49 minutes of “down time,” with a pooled sample standard deviation of 7 minutes. Suppose the manager determines a level of significance for the test equal to 0.01.

1) Write down the null and alternative hypotheses. Is this a left-, right-, or two-tailed test?

2) Calculate the t-score of the samples.

3) What should the manager conclude from this hypothesis test? Briefly explain how you came to this decision.

Answer 1

1)null hypothesis :Ho: _office =_cubicle

alternate hypothesis: Ha: _{officecubicle}  

this is two tailed hypothesis

2)

for std errror =Sp*sqrt(1/n1+1/n2)=7*sqrt(1/7+1/3)=4.83

hence test statsitic t=(x1bar-x2bar)/std error =(38-49)/4.83=-2.277

3)

at 0.01 level and (n1+n2-2=8) degree of freedom ; rejection region t<-3.355 or t>3.355

as test statstisic does not fall in rejection region we can not reject null hypothesis

we do not have evidence to conlcude that “down time” on the computer differes between  employees working in a cubicle and office,