| Question 1 of 23 | 1.0 Points |
The chi-square goodness-of-fit test can be used to test for: | A.significance of sample statistics | | B.normality | | C.difference between population variances | | D.difference between population means | Reset Selection | | Question 2 of 23 | 1.0 Points |
The data presented in the table below resulted from an experiment in which seeds of 5 different types were planted and the number of seeds that germinated within 5 weeks after planting was recorded for each seed type.At the .01 level of significance, is the proportion of seeds that germinate dependent on the seed type? | Seed Type | | Observed Frequencies | | | Germinated | Failed to Germinate | | 1 | 31 | 7 | | 2 | 57 | 33 | | 3 | 87 | 60 | | 4 | 52 | 44 | | 5 | 10 | 19 | | A.Yes, because the test value 16.86 is greater than the critical value of 13.28 | | B.Yes, because the test value 16.86 is less than the critical value of 14.86 | | C.No, because the test value 16.86 is greater than the critical value of 13.28 | | D.No, because the test value 13.28 is less than the critical value of 16.86 | Reset Selection | |
| Question 3 of 23 | 1.0 Points |
In a simple linear regression analysis, the following sum of squares are produced: = 500 = 100 = 400 The proportion of the variation inYthat is explained by the variation inXis: Reset Selection | | Question 4 of 23 | 1.0 Points |
The marketing manager of a large supermarket chain would like to use shelf space to predict the sales of pet food.For a random sample of 12 similar stores, she gathered the following information regarding the shelf space, in feet, devoted to pet food and the weekly sales in hundreds of dollars. | Store | 1 | 2 | 3 | 4 | 5 | 6 | | Shelf Space | 5 | 5 | 5 | 10 | 10 | 10 | | Weekly Sales | 1.6 | 2.2 | 1.4 | 1.9 | 2.4 | 2.6 | | Store | 7 | 8 | 9 | 10 | 11 | 12 | | Shelf Space | 15 | 15 | 15 | 20 | 20 | 20 | | Weekly Sales | 2.3 | 2.7 | 2.8 | 2.6 | 2.9 | 3.1 | What is the estimated regression equation? | A.=1.45 + 0.724x | | B.=2.63 - 0.174x | | C.=2.63 + 0.724x | | D.=1.45 + 0.074x | Reset Selection | | Question 5 of 23 | 1.0 Points |
A linear regression analysis produces the equation y = 5.32 + (-0.846)x Which of the following statements must be true? | A.As x increases, y decreases, and the correlation coefficient must be positive. | | B.As x increases, y increases, and the correlation coefficient must be positive. | | C.As x increases, y increases, and the correlation coefficient must be negative. | | D.As x increases, y decreases, and the correlation coefficient must be negative. | Reset Selection | |
| Question 6 of 23 | 1.0 Points |
Which of the following statements is true regarding the F distribution? | A.It is a distribution of negative values | | B.It is always skewed to the left | | C.It typically appears in tests of equal proportions | | D.none of the above | Reset Selection | | Question 7 of 23 | 1.0 Points |
Some defendants in criminal proceedings plead guilty and are sentenced without a trial, whereas others who plead innocent are subsequently found guilty and then are sentenced.In recent years, legal scholars have speculated as to whether sentences of those who plead guilty differ in severity from sentences for those who plead innocent and are subsequently judged guilty.Consider the data given below on defendants accused of robbery, all of whom, by the way, had previous prison records.At the .01 level of significance, do these data suggest that the proportion of all defendants in these circumstances who plead guilty and are sent to prison differs from the proportion who are sent to prison after pleading innocent and being found guilty? | | Plea | | | Guilty | Not Guilty | | Number judged guilty | n1= 191 | n2= 64 | | Number sentenced to prison | x1= 101 | x2= 56 | | Sample proportion | .529 | .875 | | A.No, because the test value -4.94 is outside the interval (-1.96, 1.96) | | B.No, because the test value -1.96 is inside the interval (-2.58, 2.58) | | C.Yes, because the test value -4.94 is outside the interval (-2.58, 2.58) | | D.Yes, because the test value 2.58 is inside the interval (-4.94, 4.94) | Reset Selection | |
| Question 8 of 23 | 1.0 Points |
A type II error occurs when: | A.the test is biased | | B.the sample mean differs from the population mean | | 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 9 of 23 | 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 = 0.69 | | B.z = 0.62 | | C.z = 1.96 | | D.t = 1.645 | Reset Selection | | Question 10 of 23 | 1.0 Points |
Which of the following statements are true of the null and alternative hypotheses? | A.Both hypotheses must be true | | B.Exactly one hypothesis must be true | | C.It is possible for neither hypothesis to be true | | D.It is possible for both hypotheses to be true | Reset Selection | |
| Question 11 of 23 | 1.0 Points |
The t- distribution for developing a confidence interval for a mean has _____ degrees of freedom. | A.n + 1 | | B.n - 2 | | C.n | | D.n - 1 | Reset Selection | | Question 12 of 23 | 1.0 Points |
In constructing a confidence interval estimate for a population mean, when we replacewith the sample standard deviation (s), we introduce a new source of variability and the sampling distribution we use is: | A.F- distribution | | B.the normal distribution | | C.t -distribution | | D.chi-square distribution | Reset Selection | |
| Question 13 of 23 | 1.0 Points |
The standard deviation of a probability distribution must be: | A.less than the value of the mean | | B.a negative number | | C.a nonnegative number | | D.a number between 0 and 1 | Reset Selection |
|
| Question 14 of 23 | 1.0 Points |
If a gambler rolls two dice and gets a sum of 10, he wins $10, and if he gets a sum of three, he wins $20.The cost to play the game is $5.What is the expectation of this game? | A.$3.06 | | B.-$2.78 | | C.-$3.06 | | D.$2.78 | Reset Selection |
|
| Question 15 of 23 | 1.0 Points |
What is the probability of drawing two queens in a row from a standard deck of cards without replacement? | A.0.0015 | | B.0.0385 | | C.0.0059 | | D.0.0045 | Reset Selection |
|
| Question 16 of 23 | 3.0 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 sport preference poll yielded the following data for men and women. Usea 5% significance level and test to determine if sport preference and gender are independent. |
| 20 | 25 | 30 | 75 | | 18 | 12 | 15 | 45 | | 38 | 37 | 45 | 120 | What is the test value for this hypothesis test? Answer: Round your answer to two decimal places. What is the critical value for this hypothesis test? Answer: Round your answer to two decimal places. What is the conclusion for this hypothesis test? Choose one. 1. Thereis sufficient evidence to support the claim that one's sport preference is dependent on one's gender. 2.Thereis not sufficient evidence to support the claim that one's sport preference is dependent on one's gender. Answer: Enter only a 1 or 2 for your answer. |
|
| Question 17 of 23 | 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 marketing manager of a large supermarket chain would like to determine the effect of shelf space (in feet) on the weekly sales of international food (in hundreds of dollars). A random sample of 12 equal sized stores is selected, with the following results: | Store | Shelf Space(X) | Weekly Sales(Y) | | 1 | 10 | 2.0 | | 2 | 10 | 2.6 | | 3 | 10 | 1.8 | | 4 | 15 | 2.3 | | 5 | 15 | 2.8 | | 6 | 15 | 3.0 | | 7 | 20 | 2.7 | | 8 | 20 | 3.1 | | 9 | 20 | 3.2 | | 10 | 25 | 3.0 | | 11 | 25 | 3.3 | | 12 | 25 | 3.5 | Based on these data, what are the least squares regression coefficients of the Y-intercept (a) and slope (b)? Place your answers, rounded to 3 decimal places , in the blanks provided. a = b = |
|
| Question 18 of 23 | 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. Are America's top chief executive officers (CEOs) really worth all that money? One way to answer this question is to look at the annual company percentage increase in revenue versus the CEO's annual percentage salary increase in that same company. Suppose that a random sample of companies yielded the following data: | percent change for corporation | 15 | 12 | 3 | 12 | 28 | 6 | 8 | 2 | | percent change for CEO | 6 | 17 | -4 | 12 | 32 | -1 | 7 | 2 | Do these data indicate that the population mean percentage increase in corporate revenue is greater than the population mean percentage increase in CEO salary? Use a 5% level of significance. What is the critical value that you would use to conduct this test of hypothesis? Place your answer, rounded to 3 decimal places, in the blank. For example, 2.345 would be a legitimate entry. |
|
| Question 19 of 23 | 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. Suppose that the average weekly earnings for employees in general automotive repair shops is $450, and that the standard deviation for the weekly earnings for such employees is $50. A sample of 100 such employees is selected at random. Find probability that the mean of the sample is less than $445. Place your answer, rounded to 4 decimal places, in the blank. For example, 0.2345 would be a legitimate entry. |
|
| Question 20 of 23 | 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 percent defective for parts produced by a manufacturing process is targeted at 4%. The process is monitored daily by taking samples of sizes n = 160 units. Suppose that todays sample contains 14 defectives. How many units would have to be sampled to be 95% confident that you can estimate the fraction of defective parts within 2% (using the information from todays sample--that is using the result that)? Place your answer, as a whole number, in the blank. For example567 would be a legitimate entry. |
|
| Question 21 of 23 | 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. Ann is applying for a bank loan to open a pizza franchise.She must first complete a written application and then, if the written application is approved, be interviewed by bank officers.If an applicants written application is not approved the applicant is not granted an interview with the bank officers.Past records for this bank show that the probability of an applicant having his or her written application approved is 0.63.Records also indicate that the interviewing committee of bank officers approves 85% of the individuals they interview.Find the probability that Anns loan request is approved.Place your answer, rounded to 2 decimal places, in the blank. For example, 0.76 would be a legitimate entry. |
|
| Question 22 of 23 | 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. Let x be a random variable representing dividend yield of Australian bank stocks. We may assume that x has a normal distribution with= 2.8%. A random sample of 16 Australian bank stocks has a sample mean dividend yield of 8.91%. For the entire Australian stock market, the mean dividend yield is=6.4%.Ifyou wanted to test to determine ifthese data indicate that the dividend yield of all Australian bank stocks is higher than 6.4%, what is the value of the test statistic? Place your answer, rounded to 3 decimal places, in the blank. For example, 2.345 would be a legitimate entry. |
|
| Question 23 of 23 | 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. An ice cream vendor sells three flavors: chocolate, strawberry, and vanilla. Forty five percent of the sales are chocolate, while 30% are strawberry, with the rest vanilla flavored. Sales are by the cone or the cup. The percentages of cones sales for chocolate, strawberry, and vanilla, are 75%, 60%, and 40%, respectively. For a randomly selected sale, define the following events: = chocolate chosen = strawberry chosen = vanilla chosen = ice cream on a cone ice cream in a cup Find the probability that the ice cream was chocolate flavor, given that it was sold in a cup.Placeyour answer, rounded to 4 decimal places, in the blank. For exampe, 0.3456 would be a legitimate entry. |
|
