San Jose State University Statistics Worksheet

12/2/22, 10:06 AMQuiz: Exam 3 Pt I (t-tests M/C)
Exam 3 Pt I (t-tests M/C)
Started: Dec 2 at 10:06am
Quiz Instructions
Question 1
2 pts
Which of the following research situations is most likely to use an independentmeasures design?
Evaluate the effectiveness of a diet program by measuring how much weight is lost during 4
weeks of dieting.
Evaluate the effectiveness of a cholesterol medication by comparing cholesterol levels before
and after the medication.
Evaluate the difference in verbal skills between 3-year-old girls and 3-year-old boys.
Evaluate the development of verbal skills between age 2 and age 3 for a sample of girls.
Question 2
2 pts
For which of the following situations would a repeated-measures (dependent-samples)
study be appropriate?
Compare attitude scores for males versus females.
Compare personality scores for individuals diagnosed with an eating disorder and those who
are not diagnosed.
Compare salary levels for college graduates and those who did not graduate from college.
Compare reaction times before and after taking a pain medication.
Question 3
2 pts
A repeated-measures (dependent-samples) study using a sample of N = 20 participants
would produce a t statistic with df = ____.
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Quiz: Exam 3 Pt I (t-tests M/C)
9
19
20
39
Question 4
2 pts
An independent-measures (independent-samples) study uses N = 15 participants in
each group to compare two treatment conditions. What is the df value for the t statistic
for this study?
14
15
28
29
Question 5
2 pts
A researcher reports t(24) = 5.30 for an independent-measures experiment. How many
individuals participated in the entire experiment?
24
25
26
12
Question 6
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2 pts
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Quiz: Exam 3 Pt I (t-tests M/C)
A research study produces a t statistic with df = 28. For this study, which of the following
designs would require a total of 30 participants?
An independent-measures (independent-samples) design
A repeated-measures (dependent-samples) design
A matched-subjects design
None of the other options would require a total of 30 participants.
Question 7
2 pts
A group of participants is measured before and after a treatment in a repeatedmeasures study. If the treatment has a consistent effect on all of the participants (for
example: they all lost a similar amount of weight), then the difference scores should
show __________.
a large mean difference
a small mean difference
a large variance
a small variance
Question 8
2 pts
In a hypothesis test, if an independent-measures t statistic has a value zero, then
__________.
the two population means must be equal
the two sample means must be equal
the two sample variances must be equal
None of the other 3 choices is correct.
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Quiz: Exam 3 Pt I (t-tests M/C)
Question 9
2 pts
An independent-measures (independent-samples) research study uses two samples,
each with n = 10 participants. If the data produce a t statistic of t = 2.095, which of the
following is the correct decision for a two-tailed hypothesis test?
Reject the null hypothesis with a = .05 but fail to reject with a = .01
Reject the null hypothesis with either a = .05 or a = .01
Fail to reject the null hypothesis with either a = .05 or a = .01
Cannot answer without additional information
Question 10
2 pts
Which of the following samples will have the smallest value for the estimated standard
error?
N = 4 with
=4
N = 4 with
=8
N = 16 with
=4
N = 16 with
=8
Question 11
2 pts
A repeated-measures (dependent-samples) study comparing two treatments with a
sample of N = 4 participants produces = 3 with SS = 48 for the set of difference
scores. What is the repeated-measures t statistic for these data?
= 1.73
3/2 = 1.50
3/4 = 0.75
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Quiz: Exam 3 Pt I (t-tests M/C)
3/16 = 0.19
Question 12
2 pts
What is the pooled variance for the following two samples?
Sample 1: n = 6 and SS = 200.
Sample 2: n = 10 and SS = 300
250
500
500/14
500/16
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12/2/22, 10:29 AM
Quiz: Exam 3 Pt II (t-tests Calculations)
Exam 3 Pt II (t-tests Calculations)
Started: Dec 2 at 10:29am
Quiz Instructions
Question 1
11 pts
Below are the number of cars sold in one week by each of 5 sales agents randomly
selected from the sales staff at a dealership. Are the sales agents selling significantly
more than 6 cars per week? (A column for the calculation of Y2 is provided as a prompt
to get you started))
Y2
Y
10
9
11
8
5
Choose from the choices on the right. Enter the number (1, 2, 3, 4, 5, 6) that would be
the correct hypothesis.
1 — μ = 6
2 — μ ≠ 6
3 — μ ≥ 6
H0:
4 — μ ≤ 6
5 — μ < 6 H1: 6 --- μ > 6
=
(2 decimal places)
SS =
21.20 (THIS IS A FREE ANSWER. JUST ENTER THIS
VALUE, AND USE IT TO CONFIRM YOUR OTHER CALCULATIONS SO FAR.)
Standard Deviation: SY =
Standard Error:
tobt =
(2 decimal places)
=
(2 decimal places)
(2 decimal places)
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Quiz: Exam 3 Pt II (t-tests Calculations)
tcrit =
(3 decimal places)
df =
(No decimals)
p value
(Enter the number 1-5 that corresponds with the correct
way to report your p value)
1 — p = n.s.
2 — p < .05 3 --- p < .025 4 --- p < .01 5 --- p < .005 Do sales agents sell significantly more than 6 cars per week? (Enter YES or NO) Question 2 14 pts You are performing research on the general health effects of having access to a gym. You have data on how many doctor office visits 11 people made over the last 3 years, 5 live near a gym, and 6 live in areas without a gym. Do the data suggest that living near a gym has an effect on the number of office visits? Gym1 No Gym2 4 3 7 2 5 3 8 1 3 2 Y12 Y22 2 Choose from the choices on the right. (Enter the number (1, 2, 3, 4, 5, 6) that would be the correct hypothesis.) H0: H1: 1 --- μ1 - μ2 = 0 2 --- μ1 - μ2 ≠ 0 3 --- μ1 - μ2 ≥ 0 4 --- μ1 - μ2 ≤ 0 5 --- μ1 - μ2 < 0 6 --- μ1 - μ2 > 0
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Quiz: Exam 3 Pt II (t-tests Calculations)
Is this is a one-tail or a two-tail test?
1=
(ENTER 1 or 2)
4.83 (2 decimal places) THIS IS A FREE ANSWER. JUST
ENTER THIS VALUE, AND USE IT TO CONFIRM YOUR OTHER CALCULATIONS SO
FAR.
2=
(2 decimal places)
SS1 =
26.83 (2 decimal places) THIS IS A FREE ANSWER. JUST
ENTER THIS VALUE, AND USE IT TO CONFIRM YOUR OTHER CALCULATIONS SO
FAR.
SS2 =
(2 decimal places)
S2p =
(2 decimal places)
=
tobt =
tcrit = ±
df =
(2 decimal places)
(2 decimal places)
(3 decimal places)
(No decimals)
Does living near a gym have an effect on the number of office visits?
(Enter YES or NO)
If you used an a of .01 instead of .05, would your results be significant?
(Enter YES or NO)
Question 3
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Quiz: Exam 3 Pt II (t-tests Calculations)
You sell mattresses. You want to claim that people sleep longer in your mattresses
than in their regular beds, so you ask people how many hours they sleep each night,
then you lend them one of your mattresses for a month, and when you go to pick up the
mattress you ask them how long they are sleeping now. Their Pre (regular bed) and
Post (your mattress) data is shown below. Can you claim that your mattresses help
people sleep longer than they would in their regular beds? (Columns for the calculation
of D and D2 are provided as a prompt to get you started)
THINK! If they sleep longer in the “Post” condition, will you get a positive or a negative
number when you calculate the difference Pre-Post? This answer will determine your
hypotheses.
Pre
Post
Customer 1
6
8
Customer 2
5
6
Customer 3
5
5
Customer 4
7
7
Customer 5
6
9
Customer 6
8
8
D
D2
Choose from the choices on the right. (Enter the number (1, 2, 3, 4, 5, 6) that would be
the correct hypothesis.)
1 — μD = 0
2 — μD ≠ 0
H0:
3 — μD ≥ 0
4 — μD ≤ 0
H1:
5 — μD < 0 6 --- μD > 0
=
SS =
(2 decimal places)
8.00 (THIS IS A FREE ANSWER. JUST ENTER THIS
VALUE, AND USE IT TO CONFIRM YOUR OTHER CALCULATIONS SO FAR.)
SD =
(2 decimal places)
S =
(2 decimal places)
tobt =
(2 decimal places)
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Quiz: Exam 3 Pt II (t-tests Calculations)
tcrit =
(3 decimal places)
df =
(No decimals)
p value
(Enter the number 1-4 that corresponds with the correct
way to report your p value)
1 — p = n.s.
2 — p < .05 3 --- p < .02 4 --- p < .01 Based on these results, can you claim that people sleep significantly longer on your mattresses? (Enter YES or NO) Not saved https://sjsu.instructure.com/courses/1488202/quizzes/1610331/take Submit Quiz 5/5 12/3/22, 9:54 PM Quiz: Exam 3 Pt III (Chi-square M/C) Exam 3 Pt III (Chi-square M/C) Started: Dec 3 at 9:54pm Quiz Instructions Question 1 2 pts In a bivariate table, the row and column totals are called data marginals cells variables Question 2 2 pts The number of degrees of freedom for a chi-square test is calculated as: (rows-1)(columns+1) (rows-1)(columns-1) (rows+1)(columns+1) (rows+1)(columns-1) Question 3 2 pts Chi-square values are always _____. positive zero https://sjsu.instructure.com/courses/1488202/quizzes/1610346/take 1/3 12/3/22, 9:54 PM Quiz: Exam 3 Pt III (Chi-square M/C) greater than 100 negative Question 4 2 pts The data for a chi-square test consist of ___________. frequencies ranks non-numerical categories numerical scores Question 5 2 pts What is referred to by the term observed frequencies? The frequencies that are hypothesized for the population being examined The frequencies found in the population being examined The frequencies computed from the null hypothesis The frequencies found in the sample data Question 6 2 pts What is referred to by the term expected frequencies? The frequencies that are hypothesized for the population being examined The frequencies found in the sample data The frequencies found in the population being examined https://sjsu.instructure.com/courses/1488202/quizzes/1610346/take 2/3 12/3/22, 9:54 PM Quiz: Exam 3 Pt III (Chi-square M/C) The frequencies computed from the null hypothesis Question 7 2 pts A researcher obtains a negative value for chi-square statistic. What can you conclude because the value is negative? There are large differences between the observed and expected frequencies. The expected frequencies are consistently larger than the observed frequencies. The observed frequencies are consistently larger than the expected frequencies. The researcher made a mistake; the value of chi-square cannot be negative. Not saved https://sjsu.instructure.com/courses/1488202/quizzes/1610346/take Submit Quiz 3/3 12/3/22, 10:01 PM Quiz: Exam 3 Pt IV (Chi-square Calculations) Exam 3 Pt IV (Chi-square Calculations) Started: Dec 3 at 10:01pm Quiz Instructions Question 1 12 pts Consider the following hypothetical data on each respondent’s region of U.S. residence and whether or not they have health insurance of some kind. Construct a bivariate table containing the appropriate percentages for each cell in the table. (Suggestion: Fill out a table of the data first (crosstabulate), and use it to answer the questions) NOTE: WHERE ASKED TO ENTER A PERCENTAGE, ENTER PERCENTAGES, NOT PROPORTIONS. ALL VALUES SHOULD BE WHOLE NUMBERS, NO DECIMALS. DON'T INCLUDE THE "%" SIGN (ALREADY THERE) Person Region Health Ins. 1 South Yes 2 South Yes 3 North No 4 North No 5 North Yes 6 North Yes 7 North Yes 8 North No 9 South Yes 10 North No 11 North Yes 12 South Yes 13 South No 14 North Yes 15 South No 16 North No 17 North No 18 South Yes https://sjsu.instructure.com/courses/1488202/quizzes/1610319/take 1/4 12/3/22, 10:01 PM Quiz: Exam 3 Pt IV (Chi-square Calculations) 19 North Yes 20 South Yes Region Health Ins. North South Row Totals Yes fo Row% 100% % % Col% % % % % % Total% No fo Row% 100% % % Col% % % % % % Total% Column Ttl fo 20 Row% Col% 100% % % 100% 100% https://sjsu.instructure.com/courses/1488202/quizzes/1610319/take 100% 2/4 12/3/22, 10:01 PM Quiz: Exam 3 Pt IV (Chi-square Calculations) Question 2 16 pts The following data were obtained from the General Social Survey. Calculate the expected frequencies, and marginal frequencies. NOTE: ALL ANSWERS SHOULD BE WHOLE NUMBERS, SO NO DECIMALS. Religious Affiliation Position on Abortion Protestant Catholic 45 60 45 50 Row Totals Support fo fe Oppose fo fe Col Totals 200 Question 3 10 pts Hypothetical data are provided below on relationship between gender and marital satisfaction. The table already includes expected frequencies (fe). Calculate a Chi-square statistic for the data in the table below, and answer the questions that follow. Gender Marital Satisfaction Satisfied Unsatisfied Column Total Male Female Row Total fo 125 75 200 fe 112.5 87.5 fo 100 100 fe 112.5 87.5 225 175 200 400 Using the table above, calculate a value for Chi-square Chi-square = (Use 2 decimal places) https://sjsu.instructure.com/courses/1488202/quizzes/1610319/take 3/4 12/3/22, 10:01 PM Quiz: Exam 3 Pt IV (Chi-square Calculations) What is the correct value for degrees of freedom (df) for this Chi-square? df = (No decimals) What is the critical value for Chi-square at alpha = .05 Chi-squarecrit= (Use 3 decimal places) Is there a significant association between Gender and Marital Satisfaction? (Enter YES or NO) How would you report the p value? (Enter the number 1-5 that corresponds with the correct way to report your p value) 1 --- p = n.s. 2 --- p < .05 3 --- p < .02 4 --- p < .01 5 --- p < .001 Not saved https://sjsu.instructure.com/courses/1488202/quizzes/1610319/take Submit Quiz 4/4