HOMEWORK 1--GENDER AND ANXIETY--SPRING, 2012 Name________________________________
Due at time of Quiz 1.
1. Use spreadsheet << T12MEANS >> to conduct estimation and hypothesis testing on the population
mean anxiety of college male and female statistics students. Assume that your data are random
samples from the relevant populations. Data are in the “Class Data” file under Part I of Stats I.
Data:
Females (X)
Anxiety scores of the FIRST EIGHT female students in section A, B, or C
of Stats I—depending on which section of Stats II you are in. For example,
If you are in section A of Stats II use section A of Stats I, etc.
Males (Y)
Anxiety scores of the FIRST ELEVEN male students in section A, B, or C
of Stats I—depending on which section of Stats II you are in. For example,
If you are in section B of Stats II use section B of Stats I, etc.
Sample
Size
Sample
Mean
Estimated Population
Standard Deviation
Females (X)
________
________
________
Males (Y)
________
________
________
a. The point estimate of the population mean is:
Females:
Males:
b. The sampling standard deviation (standard error) of the sample means is:
Females:
Males:
c. The 95% confidence interval for the population mean is:
d. (use “point estimate ± error factor” format, not LCL and UCL)
Females: __________±__________
(c)
(d)
Males: __________±__________
(c)
(d)
Test the Ho that each population mean is 5.50 against the Ha that it is not 5.50.
e. State the H0:
Females:
f.
State the Ha:
Females:
Males:
Males:
g. Use alpha = 0.05. The tt, table-t, or critical value is:
Females:
Males:
h. The tc, calculated-t or test statistic is:
Females:
i.
Males:
State the hypothesis-test conclusion for the two genders:
Females:
Males:
j.
Explain the conclusion “what to say and how to say it” :
Females:_______________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
Males:_________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
k. What is the p-value in this test?
Females:
Males:
2. Using the same data, conduct estimation and hypothesis testing on the difference
between population means.
a. The point estimate of the difference between population means is:
b. The sampling standard deviation (standard error) of the differences between sample means is:
c. The 95% confidence interval for the difference between population means is
d. (use “point estimate ± error factor” format, not LCL and UCL):
__________±__________
(c)
(d)
Test the H0 that the population means are equal against the Ha that they are not
equal.
e. State the H0:
f.
State the Ha:
g. Use alpha = 0.05. The tt, table-t, or critical value is:
h. The tc, calculated-t or test statistic is:
i.
State the hypothesis-test conclusion:
j.
Explain the conclusion “what to say and how to say it”: _________________________________
_____________________________________________________________________________
_____________________________________________________________________________
k. What is the p-value in this test?
Print these two pages first, then fill in the answers by hand.
ATTACH THE << T12MEANS >> SPREADSHEET. CIRCLE OR HIGHLIGHT, and LABEL with the item
number (1a, 1b, etc.), EVERY SPREADSHEET VALUE that you have written above. The spreadsheet
must be PRINTED ON ONE PAGE, AS LARGE AS POSSIBLE on the page. Do not print the instructions.
Delete unused rows in the data table.
Most Important: For practice, verify the spreadsheet results by calculator.