1 of 20 1.0 Points Which of the following statements are true of the null and alternative hypotheses? A.It is possible for both hypotheses to be true B.It is possible for neither hypothesis to be true C.Exactly one hypothesis must be true D.Both hypotheses must be true Reset Selection Question 2 of 20 1.0 Points A lab technician is tested for her consistency by taking multiple measurements of cholesterol levels from the same blood sample. The target accuracy is a variance in measurements of 1.2 or less. If the lab technician takes 16 measurements and the variance of the measurements in the sample is 2.2, does this provide enough evidence to reject the claim that the lab technician's accuracy is within the target accuracy? Compute the value of the appropriate test statistic. A. = 30.58 B.t = 27.50 C.= 27.50 D.z = 1.65 Reset Selection Question 3 of 20 1.0 Points Results from previous studies showed 79% of all high school seniors from a certain city plan to attend college after graduation. A random sample of 200 high school seniors from this city reveals that 162 plan to attend college. Does this indicate that the percentage has increased from that of previous studies? Test at the 5% level of significance. Compute the z or t value of the sample test statistic. A.z = 0.62 B.t = 1.645 C.z = 0.69 D.z = 1.96 Reset Selection Question 4 of 20 1.0 Points The \"Pizza Hot\" manager commits a Type I error if he/she is A.switching to new style when it is no better than old style B.staying with old style when new style is no better than old style C.switching to new style when it is better than old style D.staying with old style when new style is better Reset Selection Question 5 of 20 1.0 Points You conduct a hypothesis test and you observe values for the sample mean and sample standard deviation when n = 25 that do not lead to the rejection of H0. You calculate a pvalue of 0.0667. What will happen to the p-value if you observe the same sample mean and standard deviation for a sample size larger than 25? A.The p - value may increase or decrease B.The p - value increases C.The p - value stays the same D.The p - value decreases Reset Selection Question 6 of 20 1.0 Points A type II error occurs when: A.the sample mean differs from the population mean B.the test is biased C.the null hypothesis is incorrectly accepted when it is false D.the null hypothesis is incorrectly rejected when it is true Reset Selection Question 7 of 20 The form of the alternative hypothesis can be: 1.0 Points A.one-tailed B.two-tailed C.one or two-tailed D.neither one nor two-tailed Reset Selection Question 8 of 20 1.0 Points Smaller p-values indicate more evidence in support of the: A.quality of the researcher B.alternative hypothesis C.the reduction of variance D.null hypothesis Reset Selection Question 9 of 20 1.0 Points Which of the following values is not typically used for ? A.0.05 B.0.01 C.0.50 D.0.10 Reset Selection Question 10 of 20 1.0 Points If a teacher is trying to prove that a new method of teaching economics is more effective than a traditional one, he/she will conduct a: A.point estimate of the population parameter B.one-tailed test C.two-tailed test D.confidence interval Reset Selection Question 11 of 20 1.0 Points A manufacturer of flashlight batteries took a sample of 13 batteries from a day's production and used them continuously until they failed to work. The life lengths of the batteries, in hours, until they failed were: 342, 426, 317, 545, 264, 451, 1049, 631, 512, 266, 492, 562, and 298. At the .05 level of significance, is there evidence to suggest that the mean life length of the batteries produced by this manufacturer is more than 400 hours? A.No, because the test value 1.257 is greater than the critical value 1.115 B.No, because the p-value for this test is equal to .1164 C.Yes, because the test value 1.257 is less than the critical value 1.782 D.Yes, because the test value 1.257 is less than the critical value 2.179 Reset Selection Part 2 of 3 - Question 12 of 20 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUST be used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values. For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. A statistician wishes to test the claim that the standard deviation of the weights of firemen is greater than 25 pounds. To do so, she selected a random sample of 30 firemen and found s = 27.2 pounds. Assuming that the weights of firemen are normally distributed, if the statistician wanted to test her research hypothesis at the .05 level of significance, what is the critical value? Place your answer, rounded to 3 decimal places, in the blank. For example, 23.456 would be a legitimate entry. Question 13 of 20 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUST be used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values. For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. A survey determines that mint chocolate chip is the favorite ice cream flavor of 6% of consumers. An ice cream shop determines that of 240 customers, 18 customers stated their preference for mint chocolate chip. Find the P-value that would be used to determine if the percentage of customers who prefer mint chocolate chip ice has increased at a 5% level of significance. P-value: Round your answer to four decimal places as necessary. Question 14 of 20 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUST be used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values. For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. The ABC battery company claims that their batteries last 100 hours, on average. You decide to conduct a test to see if the company's claim is true. You believe that the mean life may be different from the 100 hours the company claims. You decide to collect data on the average battery life (in hours) of a random sample of n = 20 batteries. Some of the information related to the hypothesis test is presented below. Test of H0: = 100 versus H1: 100 Sample mean 98.5 Std error of mean 0.777 Assuming the life length of batteries is normally distributed, if you wish to conduct this test at the 0.05 level of significance, what are the critical values that you should use? Place the smaller critical value, rounded to 3 decimal places, in the first blank. For example, -1.234 would be a legitimate entry. . Place the larger critical value, rounded to 3 decimal places, in the second blank. For example, 1.234 would be a legitimate entry. Question 15 of 20 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUST be used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values. For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. The ABC battery company claims that their batteries last at least 100 hours, on average. Your experience with their batteries has been somewhat different, so you decide to conduct a test to see if the company's claim is true. You believe that the mean life is actually less than the 100 hours the company claims. You decide to collect data on the average battery life (in hours) of a random sample of n = 20 batteries. Some of the information related to the hypothesis test is presented below. Test of H0: 100 versus H1: 100 Sample mean 98.5 Std error of mean 0.777 Assuming the life length of batteries is normally distributed, what is the value of the test statistic used to conduct your test of hypothesis? Place your answer, rounded to 3 decimal places in the blank. For example, -2.345 would be a legitimate entry. Question 16 of 20 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUST be used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values. For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. A statistician wishes to test the claim that the standard deviation of the weights of firemen is greater than 25 pounds. To do so, she selected a random sample of 20 firemen and found s = 27.2 pounds. Assuming that the weights of firemen are normally distributed, to test her research hypothesis the statistician would use a chi-square test. In that case, what is the computed test value? Place your answer, rounded to 3 decimal places, in the blank. For example, 23.456 would be a legitimate entry. Question 17 of 20 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUST be used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values. For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. A survey determines that mint chocolate chip is the favorite ice cream flavor of 6% of consumers. An ice cream shop determines that of 190 customers, 15 customers stated their preference for mint chocolate chip. Find the P-value that would be used to determine if the percentage of customers who prefer mint chocolate chip ice has increased at a 5% level of significance. P-value: Round your answer to four decimal places as necessary. Part 3 of 3 Question 18 of 20 1.0 Points The p-value of a test is the smallest level of significance at which the null hypothesis can be rejected. True False Reset Selection Question 19 of 20 1.0 Points A low p-value provides evidence for accepting the null hypothesis and rejecting the alternative. True False Reset Selection Question 20 of 20 1.0 Points In order to determine the p-value, it is unnecessary to know the level of significance. True False Reset Selection