In a study of in-person vs. online statistics courses, a researcher wishes to test the claim that the average student grade in in-person stats courses is at least as high as the average student grade in online stats courses. To test this claim 70 in-person student’s grades are randomly selected, with an average of 83.7 and a standard deviation of 7.98. In addition, 60 online student’s grades are randomly selected, with an average of 85.0 and a standard deviation of 8.83. Based on this data, and using an alpha=0.20, answer the following questions.The left critical value = [left] (round to 2 decimals – if there is no left value, enter “na”)The right critical value = [right] (round to 2 decimals – if there is no right value, enter “na”)The test statistic = [ts] (round to 2 decimals)The result of the hypothesis test is [result] (enter “reject H0” or “fail to reject H0”)Is the claim supported? [support] (enter “yes” or “no”)

A consumer research firm conducts a study to compare the cleaning power of 3 different laundry detergents and 4 different water temperatures. Results are shown in the table below, with a higher number representing greater cleaning power. Perform a two-factor ANOVA and answer the following questions.What water temperature has the highest average cleaning power? [highwater] (enter the temp name, e.g. cool)What water temperature has the lowest average cleaning power? [lowwater] (enter the temp name, e.g. cool)What is the p-value in the ANOVA for the difference in the average  water temperatures? [pvalwater] (round to 3 decimals)At an alpha of 0.05, is there a significant difference in the average water temperatures? [sigtemp] (enter yes or no)What is the p-value for the difference in the average cleaning power of the detergents? [pvaldet] (round to 3 decimals)At an alpha of 0.05, is there a significant difference in average cleaning power of the different detergents? [sigdet] (enter yes or no) Det A Det B Det C Cold 27 20 19 Cool 24 16 18 Warm 29 24 25 Hot 17 13 20

The following data shows the results from trying to teach various tricks/commands (i.e., Sit, Shake, Roll Over) to young dogs (i.e., “Puppy”) and older dogs (i.e., “Old Dog”). The numbers represent how much training it takes (i.e., how many times the command must be repeated) before the dog is able to do the trick on command. Perform the appropriate ANOVA and answer the following questions.Does the analysis consider a possible interaction between the factors (i.e., the age of the dog and the type of trick) that needs to be examined? [inter] (enter yes or no)If so, what is the p-value associated with the interaction? [pint] (round to 3 decimals)Is the interaction statistically significant at alpha=0.05? [intsig] (enter yes or no)What is the is the p-value for the difference between puppies and old dogs in the average training required to learn a trick? [pcorn] (round to 3 decimals)At an alpha of 0.05, can we say the difference between puppies and older dogs is meaningful and significant? [sigage] (enter yes, no, or na if the question cannot be answered)What is the p-value for the difference between the type of tricks? [pplot] (round to 3 decimals)At an alpha of 0.05, can we say the difference in the average required training between the various tricks is meaningful and significant? [sigtrick] (enter yes, no, or na if the question cannot be answered) RollOver Shake Sit Puppy 3 4 3 Puppy 2 5 6 Puppy 4 4 4 Puppy 2 6 5 Puppy 3 7 7 Old Dog 2 9 2 Old Dog 4 10 5 Old Dog 2 11 3 Old Dog 3 13 4 Old Dog 1 7 6

Tests of the flammability of children’s sleepwear were conducted independently by three different labs. Results are shown in the table below. Perform an ANOVA and answer the following questions.What is the average flammability rating reported by Lab#2? [avglab2] (round to 2 decimals)What is the variance in flammability rating for Lab#1? [varlab1] (round to 2 decimals)What is the p-value for this ANOVA? [pval] (note: round to 3 decimals)At an alpha of 0.05, is there a significant difference in the mean of flammability between the labs? [sig] (enter yes or no) Lab#1 Lab#2 Lab#3 5.1 5.0 4.8 4.9 3.7 5.8 4.5 4.3 4.9 4.6 4.5 4.8 4.3 2.8 4.9 4.8 4.6 3.8 4.3 3.9 4.6 3.3 4.7   4.3 2.9   3.8    

Market researchers studying the demographics of soda drinkers claim that the average age of Mountain Dew drinkers is at least that of the average age of Coke drinkers.To test their claim, the researchers randomly select 300 Mountain Dew drinkers and 300 Coke drinkers. The average age of the Mountain Dew drinkers is 30.1 with a standard deviation of 8.38 years, and the average age of Coke drinkers is 30.9 with a standard deviation of 10.47 years.Based on this data, and using an alpha=0.20, answer the following questions and test the claim.The left critical value = [left] (round to 2 decimals – if there is no left value, enter “na”)The right critical value = [right] (round to 2 decimals – if there is no right value, enter “na”)The test statistic = [ts] (round to 2 decimals)The result of the hypothesis test is [result] (enter “reject H0” or “fail to reject H0”)Is the claim supported? [support] (enter “yes” or “no”)

A large buyer of transportation services wants to compare the standard deviation in delivery lead times between standard UPS and Fedex shipments.100 UPS shipments are randomly selected, and an analysis indicates a standard deviation of 4.1 days.150 Fedex shipments are randomly selected, and an analysis indicates a standard deviation of 3.6 days.Using this information, answer the following questions and test the claim that the standard deviation in delivery lead times for UPS is no different than that of Fedex, assuming alpha=0.02.(Hint: make sure you designate the sample with the larger variance as sample1 and the other as sample2 in your calculations. We are also always only interested in the right F critical value)What is the value of the F critical value? [Fcv] (round to 2 decimals)What is the value of the F test statistic? [Fts] (round to 2 decimals)What is the result of the hypothesis test? [result] (enter “reject H0” or “fail to reject H0”)Is the claim supported? [support] (enter “yes” or “no”)

To test the volatility of two stocks (ABC Company and XYZ Company), a researcher collects data on stock prices for each company over the last 30 days. Data shows the variance (s^2) in stock price for ABC is $39.34, and for XYZ Company the variance is $20.18. Use this information to test the claim that the variance in ABC is greater than the variance in XYZ stock. Assume an alpha of 0.05.(Hint: make sure you designate the sample with the larger variance as sample1 and the other as sample2 in your calculations. Also, we are always only interested in the right F critical value)What is the right F critical value? [Fcv] (round to 2 decimals)What is the value of the F test statistic? [Fts] (round to 2 decimals)What is the result of the hypothesis test? [result] (enter “reject H0” or “fail to reject H0”)Is the hypothesis supported? [support] (enter “yes” or “no”)

The following data shows human body temperatures from random samples of three different age groups. Perform an ANOVA and answer the following questions.What is the average body temperature for 30+ year olds? [avg30] (round to 2 decimals)What is the variance in body temperature for 18-20 year olds? [var18] (round to 2 decimals)What is the p-value for this ANOVA? [pval] (note: round to 3 decimals)At an alpha of 0.05, is there a significant difference in mean body temperatures between the age groups? [sig] (enter yes or no)Without further analysis, is it possible to say for sure which specific group is, or is not, different from which other specific group(s)? [diff] (enter yes or no) 18-20yrs 21-29yrs 30+yrs 98.0 99.6 97.5 98.4 98.2 98.2 97.7 99.0 97.0 98.5 98.2 97.1 97.1 97.9 96.4

The table below shows data from a study comparing what people said their annual income was (in thousands of dollars), as opposed to what they reported on their tax return. Assuming alpha=0.01, use this data to test the claim that people say they have a greater annual income than what they actually report on their taxes. Said 50 48 43 39 35 33 28 for Tax 48 48 40 37 32 34 27 What is the mean of the difference in incomes (d-bar)? [dbar] (round to 1 decimal)What is the standard deviation of the difference (s-d)? [sd] (round to 2 decimals)What is the left critical value? [cvL] (round to 2 decimals – enter “na” if there is none)What is the right critical value? [cvR] (round to 2 decimals – enter “na” if there is none)What is the value of the test statistic? [ts] (round to 2 decimals)What is the result of the hypothesis test? [result] (enter “reject H0” or “fail to reject H0”)Is the claim supported? [support] (enter “yes” or “no”)

A random sample of repair costs for BMW’s involved in crashes consisted of 5 BMW’s, with repair costs shown in the table below. Use an alpha=0.02 to answer the following questions related to a claim that the mean repair cost for all BMW crashes is $3,000. $2,797 $2,571 $2,904 $3,147 $2,418 H0: mu [c1] $3,000 (enter correct sign(s))H1: mu [c2] $3,000 (enter correct sign(s))The claim is [m1] (enter H0 or H1)The critical value on the left, if there is one = [cv1] (round to 3 decimals-if none, enter “na”)The critical value on the right, if there is one = [cv2] (round to 3 decimals-if none, enter “na”)The test statistic = [ts] (round to 3 decimals)The result of the hypothesis test of H0 is [result] (enter “reject H0” or “fail to reject H0”)Is the claim supported? [support] (enter yes or no)