This module provides a homework of F Distribution and One-Way ANOVA as a part of Collaborative Statistics collection (col10522) by Barbara Illowsky and Susan Dean.
Use a solution sheet to conduct the following hypothesis tests. The solution sheet can be found in the Table of Contents 14. Appendix.
Three students, Linda, Tuan, and Javier, are given 5 laboratory rats each for a nutritional experiment. Each rat's weight is recorded in grams. Linda feeds her rats Formula A, Tuan feeds his rats Formula B, and Javier feeds his rats Formula C. At the end of a specified time period, each rat is weighed again and the net gain in grams is recorded. Using a significance level of 10%, test the hypothesis that the three formulas produce the same mean weight gain.
Weights of student lab rats
Linda's rats
Tuan's rats
Javier's rats
43.5
47.0
51.2
39.4
40.5
40.9
41.3
38.9
37.9
46.0
46.3
45.0
38.2
44.2
48.6
:
;
0.67
0.5305
Decision: Do not reject null; Conclusion: There is insufficient evidence to conclude that the means are different.
A grassroots group opposed to a proposed increase in the gas tax claimed that the increase would hurt working-class people the most, since they commute the farthest to work. Suppose that the group randomly surveyed 24 individuals and asked them their daily one-way commuting mileage. The results are below. Using a 5% significance level, test the hypothesis that the 3 mean commuting mileages are the same.
Refer to
Exercise 13.8.1 . Determine whether or not the variance in weight gain is statistically the same among Javier’s and Linda’s rats.
;
3.00
.
Using the TI-83+/84+ function 2-SampFtest, you get the the test statistic as 2.9986 and p-value directly as 0.3127. If you input the lists in a different order, you get a test statistic of 0.3335 but the p-value is the same because this is a two-tailed test.
Decision: Do not reject null; Conclusion: There is insufficient evidence to conclude that the variances are different.
Refer to
Exercise 13.8.2 above . Determine whether or not the variance in mileage driven is statistically the same among the working class and professional (middle income) groups.
Examine the 7 practice laps. Determine whether the mean lap time is statistically the same for the 7 practice laps, or if there is at least one lap that has a different mean time from the others.
;
1.69
0.1319
Decision: Do not reject null; Conclusion: There is insufficient evidence to conclude that the mean lap times are different.
Step 1: Find the mean. To find the mean, add up all the scores, then divide them by the number of scores. ...
Step 2: Find each score's deviation from the mean. ...
Step 3: Square each deviation from the mean. ...
Step 4: Find the sum of squares. ...
Step 5: Divide the sum of squares by n – 1 or N.
The sample of 16 students is taken. The average age in the sample was 22 years with astandard deviation of 6 years. Construct a 95% confidence interval for the age of the population.
Bhartdarshan' is an internet-based travel agency wherein customer can see videos of the cities they plant to visit. The number of hits daily is a normally distributed random variable with a mean of 10,000 and a standard deviation of 2,400
a. what is the probability of getting more than 12,000 hits?
b. what is the probability of getting fewer than 9,000 hits?
Bhartdarshan'is an internet-based travel agency wherein customer can see videos of the cities they plan to visit. The number of hits daily is a normally distributed random variable with a mean of 10,000 and a standard deviation of 2,400.
a. What is the probability of getting more than 12,000 hits
