Scores on the Stanford-Binet Intelligence Test (IQ) are normally distributed with mean µ = 100 and standard deviation σ = 16.
If a random sample of 49 individuals are selected, calculate the probability that the sample mean IQ is less than 96. (round your answer to the nearest four decimal places)
In: Statistics and Probability
You are experiencing pressure from administrators to cut the Peer Mentor Program in order to save money. Their argument is that the Academic Success Program alone is enough to help students succeed. After meeting with students and their peer mentors, you feel confident that the Peer Mentor Program provides something that the Academic Success Program does not: a greater feeling of being connected to the campus community. To support your argument, you have the students complete the Connected On Campus Scale at the end of Year 1. You need to compare Groups 1 and 2 on their Connected On Campus Scale (COC) scores at the end of Year 1, to determine whether your argument is true. Select the appropriate test to perform and conduct a two-tailed testusing an alpha of .05. Use r2 for your effect size.
Group |
CSS Week 1 |
CSS After Year 1 |
COC |
Group |
CSS Week 1 |
CSS After Year 1 |
COC |
|
1 |
50 |
60 |
5 |
3 |
50 |
70 |
9 |
|
1 |
45 |
55 |
6 |
3 |
40 |
60 |
8 |
|
1 |
40 |
50 |
6 |
3 |
40 |
60 |
10 |
|
1 |
40 |
50 |
7 |
3 |
35 |
55 |
9 |
|
1 |
35 |
40 |
7 |
3 |
30 |
50 |
6 |
|
1 |
30 |
40 |
5 |
3 |
35 |
55 |
6 |
|
1 |
30 |
40 |
7 |
3 |
30 |
50 |
5 |
|
1 |
35 |
45 |
4 |
3 |
35 |
55 |
4 |
|
1 |
30 |
40 |
6 |
3 |
30 |
50 |
7 |
|
1 |
35 |
45 |
6 |
3 |
45 |
65 |
6 |
|
2 |
50 |
55 |
10 |
4 |
50 |
50 |
10 |
|
2 |
40 |
50 |
8 |
4 |
30 |
30 |
7 |
|
2 |
35 |
42 |
9 |
4 |
30 |
30 |
4 |
|
2 |
45 |
55 |
9 |
4 |
35 |
35 |
9 |
2 |
30 |
38 |
7 |
4 |
35 |
35 |
9 |
|
2 |
40 |
50 |
8 |
4 |
45 |
45 |
10 |
|
2 |
40 |
45 |
5 |
4 |
40 |
40 |
5 |
|
2 |
30 |
40 |
6 |
4 |
40 |
40 |
6 |
|
2 |
35 |
46 |
9 |
4 |
35 |
35 |
5 |
|
2 |
30 |
37 |
7 |
4 |
30 |
30 |
7 |
5a) What is the appropriate test statistic and why? (1 pt)
5b) What are the degrees of freedom? (1 pt) _________________
5c) What is your decision rule? (1 pt)
5d) Calculate and interpret r2. What information does this provide? (2 pts)
5e) Report the results using standard format. (1 pts)
5f) What are the means for each group? (1 pt)
5g) Can the data support your argument to administrators? (1 pt)
In: Statistics and Probability
Before every flight, a pilot must verify that the total weight of the load aboard their aircraft is less than the maximum allowable load for that type of aircraft. Suppose a commercial aircraft can carry 39 passengers, and a flight has fuel and baggage that allows for a total passenger load of 6,513 lb. Suppose the pilot sees that the plane is full and all passengers are adult men. The aircraft will be overloaded if the mean weight of the passengers is greater than 6,513 lb/39 passengers = 167 lb/passenger. Assuming that weights of adult men are normally distributed with a mean of 179.8 lb and a standard deviation of 37.6 lb, hat is the probability that the aircraft is overloaded? Round your answer to three decimal places; add trailing zeros as needed. P(aircraft is overloaded) = [OLProb].
In: Statistics and Probability
Test the hypothesis using the P-value approach.
Upper H 0 : p equals 0.50 versus Upper H 1 : p less than 0.50
n equals 150 comma x equals 66 comma alpha equals 0.10
Perform the test using the P-value approach.
P-valueequals
nothing (Round to four decimal places as needed.)
In: Statistics and Probability
In: Statistics and Probability
The Economic Policy Institute periodically issues reports on wages of entry-level workers. The institute reported that entry-level wages for male college graduates were $21.68 per hour and for female college graduates were $18.80 per hour in 2011. Assume that the standard deviation for male graduates is $2.30, and for female graduates, it is $2.05.
(a) | What is the sampling distribution of x for a random sample of 50 male college graduates? If required, round your answer to four decimal places. |
(b) | What is the sampling distribution of x for a random sample of 50 female college graduates? If required, round your answer to four decimal places |
In: Statistics and Probability
One college class had a total of
8080
students. The average score for the class on the last exam was
83.983.9
with a standard deviation of
5.85.8.
A random sample of
3232
students was selected.
a. Calculate the standard error of the mean.
b. What is the probability that the sample mean will be less than
8585?
c. What is the probability that the sample mean will be more than
8484?
d. What is the probability that the sample mean will be between
82.582.5
and
84.584.5?
a. The standard error of the mean is
nothing.
(Round to two decimal places as needed.)
b. The probability that the sample mean will be less than
8585
is
nothing.
(Round to four decimal places as needed.)
c. The probability that the sample mean will be more than
8484
is
nothing.
(Round to four decimal places as needed.)
d. The probability that the sample mean will be between
82.582.5
and
84.584.5
is
nothing.
(Round to four decimal places as needed.)
In: Statistics and Probability
For the past
112112
years, a certain state suffered
2828
direct hits from major (category 3 to 5) hurricanes. Assume that this was typical and the number of hits per year follows a Poisson distribution. Complete parts (a) through (d).
(a) What is the probability that the state will not be hit by any major hurricanes in a single year?
The probability is
1-The number of hits to a website follows a Poisson process. Hits occur at the rate of
1.0 per minute1.0 per minute
between 7:00 P.M. and
99:00
P.M. Given below are three scenarios for the number of hits to the website. Compute the probability of each scenario between
8 : 27 P.M.8:27 P.M.
and
88:3535
P.M. Interpret each result.
(a) exactly fivefive
(b) fewer than fivefive
(c) at least fivefive
2-Determine the required value of the missing probability to make the distribution a discrete probability distribution. x P(x) 3 0.35 0.35 4 ? 5 0.16 0.16 6 0.27 0.27 P(4) =
In: Statistics and Probability
As of Friday morning, health officials have confirmed at least 39,140 total cases in New York State. The estimated population of the state was19.45 million residents in 2019.
1- Construct a 99% confidence interval of the percentage of New Yorkers likely infected and interpret your results. National Institute of Allergy and Infectious Diseases director Anthony Fauci says 1/1000 New Yorkers likely infected.
2- Many others claim that the percentage of infected New Yorkers is higher than what Dr. Fauci says. Please, conduct appropriate test of hypothesis to test that claim using a significance level 0.01
In: Statistics and Probability
The annual per capita consumption of bottled water was 33.1 gallons. Assume that the per capita consumption of bottled water is approximately normally distributed with a mean of 33.1 and a standard deviation of 11 gallons.
a. What is the probability that someone consumed more than 38 gallons of bottled water?
b. What is the probability that someone consumed between 30 and 40 gallons of bottled water?
c. What is the probability that someone consumed less than 30 gallons of bottled water?
d. 90% of people consumed less than how many gallons of bottled water?
In: Statistics and Probability
The following data represent the level of health and the level of education for a random sample of 1815 residents. |
Education |
Excellent |
Good |
Fair |
Poor |
|
---|---|---|---|---|---|---|
Not a H.S. graduate |
105 |
148 |
105 |
116 |
||
H.S. graduate |
118 |
129 |
110 |
119 |
||
Some college |
116 |
146 |
117 |
124 |
||
Bachelor Degree or higher |
68 |
142 |
59 |
93 |
Make the proper conclusion. Choose the correct answer below.
A. Fail to reject H0. There is sufficient evidence that level of education and health are associated.
B. Reject H0. There is not sufficient evidence that level of education and health are associated.
C. Fail to reject H0. There is not sufficient evidence that level of education and health are associated.
D. Reject H0. There is sufficient evidence that level of education and health are associated.
In: Statistics and Probability
39 |
35 |
84 |
68 |
72 |
52 |
46 |
60 |
50 |
55 |
60 |
57 |
55 |
56 |
73 |
74 |
78 |
63 |
70 |
49 |
56 |
91 |
57 |
54 |
50 |
41 |
59 |
57 |
62 |
59 |
44 |
79 |
62 |
57 |
51 |
85 |
67 |
69 |
52 |
85 |
49 |
66 |
56 |
60 |
56 |
46 |
64 |
60 |
In: Statistics and Probability
Given a standardized normal distribution (with a mean of 0 and a
standard deviation of 1) complete parts (a) through (d)
a. The probability that Z is less than -1.59 is _______
b. The probability that Z is greater than 1.81 is________
c. The probability that Z is between -1.59 and 1.81 is______
d. The probability that Z is less than -1.59 or greater than
1.81______
In: Statistics and Probability
An elevator has a placard stating that the maximum capacity is 1610 lblong dash10 passengers. So, 10 adult male passengers can have a mean weight of up to 1610 divided by 10 equals 161 pounds. If the elevator is loaded with 10 adult male passengers, find the probability that it is overloaded because they have a mean weight greater than 161 lb. (Assume that weights of males are normally distributed with a mean of 171 lb and a standard deviation of 28 lb.) Does this elevator appear to be safe?
In: Statistics and Probability
What is a two sampled independent test? Give an
example.
In: Statistics and Probability