Posted Assignment 5
1.
A psychologist interested in the dating habits of college undergraduates samples
10 students and determines the number of dates they have had in the last month.
Given the scores 1, 8, 12,3, 8, 14, 4, 5, 8, 16, compute the following:
a. Mean
b. Median
c. Mode
d. Range
e. Standard Deviation
f. Variance
2.
The Pearson r and Spearman rho correlation coefficients are related. Is this
statement correct? Explain.
3.
What effect does decreasing the range of the paired scores have on the correlation
efficient?
4.
If you are randomly sampling one at a time with replacement from a bag that
contains eight blue marbles, seven red marbles, and five green marbles, what is
the probability of obtaining
a. A blue marble in one draw of the bag?
b. Three blue marbles in three draws from the bag?
c. A red, a green, and a blue marble in that order in three draws from the
bag?
d. At least two red marbles in three draws from the bag?
5. Candidate A commissions a sample of 500 voters to ask whether they will vote for
)
him or his opponent. A total of 187 ( p = .374 ) said they would vote for him.
Construct a 95% confidence interval for the proportion of all voters who favor his
candidacy.
6. A school system wants to know what proportion of its students has vaccination
certificates on file. It randomly samples 200 records and finds that 38% of the
students have filed certificates. Construct a 99% confidence interval for the
proportion of all students having a certificate on file.