Randomly selected students in a statistics class were asked to
report the number of hours they slept on weeknights and on
weekends. At α = 0.05. Can it be claimed that the scores on 2 tests
are correlated on 0.01 significance level?
Student #: 1 2 3 4 5 6 7 8
Test 1: 67 88 76 88 91 95 79 71
Test 2: 69 78 76 84 86 96 70 68
G. A sample of 9 mothers was taken. The mothers were asked the
age of their oldest child. You are given their responses below.
3 12 4 7 14 6 2 9 11
a. Compute the mean.
b. Compute the variance.
c. Compute the standard deviation.
d. Compute the coefficient of variation.
e. Determine the 25th percentile.
f. Determine the median g. Determine the 75th percentile.
h. Determine the range.
In an activity in a statistics class, students were asked if
they had ever been pulled over by a police of?cer while driving.
They following table summarizes results, as counts, classi?ed by
sex.
(SHOW YOUR WORK)
Ever
Pulled
Over
by Police?
Sex
No
Yes
Total
Male
7
16
Female
20
21
Total
Ever
Pulled
Over
by Police?
Sex
No
Yes
Total
Male
Female
Total
(b) (3 points) Multiply all counts in the table by 10. (The blank
table is for...
In a class students were asked to report their gender and
whether they had ever been in a car accident. Results are shown in
the following table:
Ever had a car accident?
Gender
Yes
No
Male
10
10
Female
5
24
We want to test if car accident and gender are
related or not.
What is the expected frequency of male and car accident?
[Answer to 2 decimal places.]
Tries 0/5
What is the expected frequency of male and no...
Students in a statistics class were asked which of three
lifetime achievements they would most like to win: a Nobel Prize,
an Academy Award, or an Olympic Gold Medal. They were also asked to
indicate their gender. Results are shown in the following table:
Female Male Nobel Prize 12 5 Academy Award 8 2 Olympic Gold Medal
10 18 Suppose that you were to conduct a chi-square test on these
data. 1. State the appropriate null hypothesis in words. 2....
Two sections of a class in statistics were taught by two
different methods. Students’ scores on a standardized test are
shown in Table 5.12 . Do the results present evidence of a
difference in the effectiveness of the two methods? (Use α
= 0.05.)
Class A: 74, 97, 79, 88, 78, 93, 76, 75, 82, 86, 100, 94
Class B: 78, 92, 94, 78, 71, 85, 70, 79, 76, 93, 82, 69, 84
Include R code.
Statistics grades: In a statistics class of 47 students, there
were 17 men and 30 women. Three of the men and four of the women
received an A in the course. A student is chosen at random from the
class. (a) Find the probability that the student is a woman. (b)
Find the probability that the student received an A. (c) Find the
probability that the student is a woman or received an A. (d) Find
the probability that the...
A statistics professor asked her students whether or not they
were registered to vote. In a sample of 50 of her students
(randomly sampled from her 700 students), 35 said they were
registered to vote.
Questions 1 - 6 pertain to scenario 1.
Question 1 (1 point)
Which of the following properly explains the 95% confidence
interval for the true proportion of the professor's students who
were registered to vote?
Question 1 options:
a)
We are 95 % confident that...
A random sample of 20 workers in a factory were asked to report
the age of their car and how many miles the vehicle had on it. A
computer printout resulted in the following information.
Variable
Coef
SE Coef
t-ratio
Prob
Constant
7288.54
6591
1.11
<0.2826
Age
11630.6
1249
9.31
<0.0001
R sq = 82%
R sq adj = 81.1%
s = 19280
Find the LSRL
A new worker starts next week and we know that his car is 7...
Students enrolled in an introductory statistics course at a
university were asked to take a survey that indicated whether the
student’s learning style was more visual or verbal. Each student
received a numerical score ranging from -11 to +11. Negative scores
indicated a visual learner, and positive scores indicated a verbal
learner. The closer the score was to -11 or +11, the stronger the
student’s inclination toward that learning style. A score of 0
would indicate neutrality between visual or...