standard deviation
1. The standard deviation of the diameter at breast height, or DBH, of the slash pine tree is less than one inch. Identify the Type I error. (Points : 1) 
[removed] Fail to support the claim σ < 1 when σ < 1 is true.
[removed] Support the claim μ < 1 when μ = 1 is true.
[removed] Support the claim σ < 1 when σ = 1 is true.
[removed] Fail to support the claim μ < 1 when μ < 1 is true.
1a. The EPA claims that fluoride in children’s drinking water should be at a mean level of less than 1.2 ppm, or parts per million, to reduce the number of dental cavities. Identify the Type I error. (Points : 1) 
[removed] Fail to support the claim σ < 1.2 when σ < 1.2 is true.
[removed] Support the claim μ < 1.2 when μ = 1.2 is true.
[removed] Support the claim σ < 1.2 when σ = 1.2 is true.
[removed] Fail to support the claim μ < 1.2 when μ < 1.2 is true.
2. Biologists are investigating if their efforts to prevent erosion on the bank of a stream have been statistically significant. For this stream, a narrow channel width is a good indicator that erosion is not occurring. Test the claim that the mean width of ten locations within the stream is greater than 3.7 meters. Assume that a simple random sample has been taken, the population standard deviation is not known, and the population is normally distributed. Use the following sample data:
3.3 3.3 3.5 4.9 3.5 4.1 4.1 5 7.3 6.2
What is the Pvalue associated with your test statistic? Report your answer with three decimals, e.g., .987 (Points : 1)

3. Researchers studying sleep loss followed the length of sleep, in hours, of 10 individuals with insomnia before and after cognitive behavioral therapy (CBT). Assume a .05 significance level to test the claim that there is a difference between the length of sleep of individuals before and after CBT. Also, assume the data consist of matched pairs, the samples are simple random samples, and the pairs of values are from a population having a distribution that is approximately normal.
Individual  1  2  3  4  5  6  7  8  9  10 
Before  6  5  4  5  3  4  5  3  4  2 
CBT  
After  8  8  7  6  7  6  6  5  7  5 
CBT 
Construct a 95% confidence interval estimate of the mean difference between the lengths of sleep. Give your answer with two decimals, e.g., (12.34,56.78) (Points : 0.5)
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3a. Scientists, researching large woody debris (LWD), surveyed the number of LWD pieces from aerial photos taken annually for the past 35 years at two different sites. Over the 35 years of photos examined, the first site had a mean number of LWD pieces per hectare per year (LWD/ha/yr) of 3.7 pieces with a standard deviation of 1.9. The second site had a mean number of LWD/ha/yr of 4.3 with a standard deviation of 2.4. Assume a .05 significance level for testing the claim that the mean LWD/ha at the first site had less than the mean LWD/ha/yr at the second site. Also, assume the two samples are independent simple random samples selected from normally distributed populations, but do not assume that the population standard deviations are equal.
Construct a 90% confidence interval for the difference between the two means. Give your answer with two decimals, e.g., (12.34,56.78) (Points : 0.5)
4. The paired data consist of the cost of regionally advertising (in thousands of dollars) a certain pharmaceutical drug and the number of new prescriptions written (in thousands).
Cost  9  2  3  4  2  5  9  10 
Number  85  52  55  68  67  86  83  73 
Find the value of the linear correlation coefficient r. Give your answer to three decimals, e.g., .987. (Points : 0.5)
4a. The paired data consist of the cost of regionally advertising (in thousands of dollars) a certain pharmaceutical drug and the number of new prescriptions written (in thousands).
Cost  9  2  3  4  2  5  9  10 
Number  85  52  55  68  67  86  83  73 
Find the predicted value of the number of new prescriptions written if $6000 is spent in regional advertising. Give your answer as an integer. (Points : 0.5)
[removed]
5. Use a .05 significance level and the observed frequencies of 70 Neonatal deaths to test the claim that number of neonatal deaths on each day of the week is equally likely.
Mon  Tues  Wed  Thurs  Fri  Sat  Sun 
10  9  5  8  15  12  11 
Determine the value of the χ^{2} test statistic. Give your answer to two decimals, e.g., 12.34 (Points : 0.5)
5a. Use a .05 significance level and the observed frequencies of 144 drowning at the beaches of a randomly selected coastal state to test the claim that the number of drowning for each month is equally likely.
Jan  Feb  Mar  Apr  May  June  July  Aug  Sept  Oct  Nov  Dec 
1  3  2  7  14  20  37  33  16  6  2  3 
Determine the value of the χ^{2} test statistic. Give your answer to two decimals, e.g., 12.34 . (Points : 0.5)
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6. Using a .01 significance level, test the claim that the proportions of fear/do not fear responses are the same for male and female dental patients.
Gender
Male  Female  
Fear Dentistry  48  70 
Do Not Fear Dentistry  21  32 
Do you reject the null hypothesis, at the .01 significance level? Enter Y for yes (reject), N for no (fail to reject). (Points : 0.5)

7. The table represents results from an experiment with patients afflicted in both eyes with glaucoma. Each patient was treated in one eye with laser surgery and in the other eye was treated with eye drops. Using a .05 significance level, apply McNemar’s test to test the following claim: The proportion of patients with no improvement on the laser treated eye and an improvement on the drops treated eye is the same as the proportion of patients with an improvement on the laser treated eye and no improvement on the drops treated eye.
Eye Drop Treatment 
Improvement  No Improvement  
Laser Surgery  Improvement  15  10 
Treatment  No Improvement  50  25 
Determine the value of the χ^{2} test statistic. Give your answer to two decimals, e.g., 12.34 . (Points : 0.5)
7a. The table represents results from an experiment with patients afflicted with eczema on both arms. Each patient was treated with an immune modulator cream on one arm and a topical steroid cream on the other arm. Using a .05 significance level, apply McNemar’s test to test the following claim: The proportion of patients with no cure on the immune modulator treated arm and a cure on the topical steroid treated arm is the same as the proportion of patients with a cure on the immune modulator treated arm and no cure on the topical steroid treated arm.
Immune Modulator Cream 
Cure  No Cure  
Topical Steroid  Cure  25  11 
Cream  No Cure  42  22 
Do you reject the null hypothesis, at the .05 significance level? Enter Y for yes (reject), N for no (fail to reject). (Points : 0.5)
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8.For a study on Type 1 diabetes, medical graduate students subdivided the United States into four study regions (Northeast, Southeast, Southwest, and Northwest). The students randomly selected seven patients per region and recorded the number of times during a randomly selected month that each patient used insulin shots to regulate blood sugar levels. Use OneWay ANOVA at a .05 significance level to test the claim that the means from the different regions are not the same.
Mean number of times patients used insulin shots to regulate blood sugar levels
Northeast  Southeast  Southwest  Northwest  
4  6  4  4  
3  5  5  4  
3  6  6  5  
4  8  6  6  
3  6  7  3  
2  6  5  5  
5  8  4  3  
Do you reject the null hypothesis, at the .05 significance level? Enter Y for yes (reject), N for no (fail to reject). (Points : 0.5
8a. Geneticists studying carriers of genetic diseases followed subjects subdivided by race. Researchers randomly selected seven patients per race who had been identified as carrying a certain gene for a genetic disease; these patients were followed to determine the number of their siblings who also carried the gene for the genetic disease. Use a OneWay ANOVA at a .05 significance level to test the claim that the means from the different races are not all the same.
Caucasian  AfricanAmerican  Other 
2  0  0 
3  0  1 
3  1  2 
3  2  2 
4  2  2 
5  2  3 
5  4  4 
Determine the value of the F test statistic. Give your answer to two decimals, e.g., 12.34 . (Points : 0.5)
[removed]
9. The reason we cannot use multiple ttests to claim that four populations have the same mean is that we increase the likelihood of a type I error. (Points : 1) 
[removed] True
[removed] False
9a.
If there is only one observation per cell in a TwoWay ANOVA, and it can be assumed there is not an interaction between factors, then we can proceed to interpret the results of the row and column effects. (Points : 1) 
[removed] True
[removed] False
10.Use the following technology display from a TwoWay ANOVA to answer this question. Biologists studying habitat use in Lepidopteran moths measured the number of savannah moths found at three randomly selected prairie sites with two potential habitat interferences (expansion of row crops and grazing). Use a .05 significance level.
Source  Df  SS  MS  F  P 
Site  2  .1905  .0952  .0381  .9627 
Habitat  1  304.0238  304.0238  121.6095  .0000 
Site*Habitat  2  .1905  .0952  .0381  .9627 
What is the value of the F test statistic for the site effect? (Points : 0.5)
10a. Use the following technology display from a TwoWay ANOVA to answer this question. Biologists studying habitat use in Lepidopteran moths measured the number of savannah moths found at three randomly selected prairie sites with two potential habitat interferences (expansion of row crops and grazing). Use a .05 significance level.
Source  Df  SS  MS  F  P 
Site  2  .1905  .0952  .0381  .9627 
Habitat  1  304.0238  304.0238  121.6095  .0000 
Site*Habitat  2  .1905  .0952  .0381  .9627 
Do you reject the null hypothesis about the site effect, at the .05 significance level? Enter Y for yes (reject), N for no (fail to reject). (Points : 0.5)
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