Bstat Test 2

28. Mileage was recorded for a sample of 100 tires. The average tread life was 50,000 miles with a standard deviation of 3,500 miles. What is the best estimate of the average tread life for the population of tires? A. 50,000 B. 3,500 C. (50,000/100) D. (3,500/100) E. none of the above would provide a good estimate

A. 50,000

18. The weight of people is A. A continuous random variable B. A discrete random variable C. Interval data D. Ordinal data E. None of the above

A. A continuous random variable

38. What is a Type II error? A. Accepting a false null hypothesis B. Rejecting a false null hypothesis C. Accepting a false alternate hypothesis D. Rejecting a false alternate hypothesis E. Rejecting a true null hypothesis

A. Accepting a false null hypothesis

29. What kind of distribution is the t distribution? A. Continuous B. Discrete C. sampling D. standard normal E. very wide and very flat

A. Continuous

6. For a data set with some variation in the data and an even number of observations, half are greater than the A. Median B. Mode C. Mean D. All of the above E. None of the above

A. Median

What type of analysis is used to determine if there is a difference in sales between... A. One way ANOVA B. Two way ANOVA C. Regression analysis D. Correlation analysis E. None of the above answers are correct

A. One way ANOVA

35. A null hypothesis makes a claim about a A. Population parameter B. Sample Statistic C. Sample mean D. z-value E. any of the above

A. Population Parameter

56. A regression equation is generally used to: a. Predict the value of the dependent variable for a given value of the independent variable b. Predict the value of the independent variable for a given value of the dependent variable c. Measure the strength of the association between two variables d. All of the above

A. Predict the values of the dependent variable for a given value of the independent variable

54. If the correlation between two variables is close to one, the association is? a. Strong b. Moderate c. Weak d. Nonexistent

A. Strong

60. A method of determining if there are differences between... a. The Kruskal-Waillis Test b. The Wilcoxon Rank-Sum test c. The wilcoxon signed rank test d. None of the above

A. The Kruskal-Wallis Test

What is the decision for #14? A. The null hypotheis should be rejected B. Null hypothesis should not be rejected C. Additional data should be collected D. More information is required before making a decision

A. The null hypothesis should be rejected

27. Which of the following would be used as a point estimate for the population mean? A. the sample mean B. the test statistic C. the sample standard deviation D. the population mean E. the z value

A. The sample mean

50. In ANOVA, the variation that is explained by the factor is: a. The Variation between the samples b. The variation within the samples c. The error variation d. The standard error

A. The variation between the samples

What is the answer to the research question for #14? A. There is a difference among the four sales training B. There is not a difference among the four sales training C. The sales training is useful

A. There is a difference among the four sales training

What is the factor for #14? A. Training method B. Amount of sales C. The trainees D. The four groups

A. Training Method

12. The sum of the deviations from the mean is A. Zero B. The Variance C. The standard deviation D. The range E. Unknown

A. Zero

30. How is the t-distribution different from the z distribution? A. the t has more variability B. the t is a continuous distribution C. the t has a mean score of zero D. the t is a discrete distribution E. both A and B above are differences

A. the t has more variability

48. Which statement is correct about the F distribution? a. The values cannot be negative b. The values cannot be positive c. The values can be negative, zero, or positive d. It is negatively skewed

A. the values cannot be negative

51. Which of the following values would indicate a stronger association base... a. 0 b. -.97 c. .83 d. 100

B. -.97

36. Using a .05 level of alpha for a one population test with a sample size of 25, what is the rejection region value for a one-tailed, upper tail, hypothesis test? A. 1.96 B. 1.711 C. 2.060 D. 2.064

B. 1.711

49. An F test statistic is: a. A standard error b. A ratio of two variances c. The difference between two or more means d. A population parameter

B. A ratio of two variances

33. University officials say that a fee increase will be implemented if more than 75% of the voting student population supports the fee increase. If a sample of students reveals a 95% confidence interval of [0.71, 0.83], what conclusion can be drawn based on the interval? A. conclude that another sample is needed, because this one was not representative B. conclude it should not be implemented C. conclude is should be implemented D. this interval does not allow any conclusion to be drawn

B. Conclude it should not implemented

3. What type of variable is the amount of time spent sleeping per day? A. Interval B. Continuous C. Ordinal D. Discrete E. None of the above

B. Continuous

43. During hypothesis testing, the initial assumption about the null hypothesis is that A. it is false B. it is true C. it is unknown D. no assumption is made

B. It is true

59. Statistical methods that do not generally make the assumption... a. Parametric methods b. Nonparametric methods c. Analysis of variance methods d. None of the above

B. Non parametric methods

41. Based on the Nielsen ratings, the local CBS affiliate claims its 11:00 PM newscast reaches more than 41% of the viewing audience in the area. In a sample of 100 viewers, 36% indicated that they watch the late evening news on this local CBS station. What is the null hypothesis? A. π > 0.41 B. π ≤ 0.41 C. π ≤ 0.36 D. π > 0.36 E. π ≥ 0.36

B. Pi is less than or equal to .41

23. The different between a population parameter and the sample statistic is A. At the center of a normal distribution B. Sampling error C. Usually very large D. Usually very small E. None of the above

B. Sampling Error

21. If we choose a random starting point and then select every fifth invoice in a file, what type of sampling is being employed? A. Simple random sampling B. Systematic sampling C. Stratified random sampling D. Cluster sampling E. None of the above

B. Systematic Sampling

What is the response variable for #14? A. Training method B. amount of sales C. The trainees D. The four groups E. none of the above answers is correct

B. The amount of sales

46. In the analysis of variable procedure (ANOVA) the "factor" might also be called: a. The dependent b. The independent c. The response variable d. The test static

B. The independent

24. The mean of the sample means is A. the sample mean B. the population mean C. unable to be determined D. usually smaller than the population mean E. none of the above

B. The population mean

32. Which of the following is true? A. If the results of a hypothesis test are statistically significant, they must also have practical significance B. The results of a hypothesis test can have statistical significance without having practical significance C. The results of a hypothesis test cannot have both statically significance and practical significance and practical significance D. none of the above is true

B. The results of a hypothesis test can have statistical significance without having practical significance

13. What is the relationship between the variance and the standard deviation? A. Variance is the square root of the standard deviation B. Variance is the square of the standard deviation C. Variance is double the standard deviation D. Variance is half of the standard deviation E. There is no relationship between the variance and the standard deviation

B. Variance is the square of the standard deviation

31. A test to determine if the mean of a population is greater than 40 resulted in a test statistic of 1.05. The sample size was 10. What is the p-value? A. less than 0.20 B. greater than 0.10 C. greater than .20 D. 0.1469 E. none of the above

B. greater than 0.10

34. If a confidence interval is too wide to be useful, what can be done? A. Increase the level of confidence B. Increase the sample size C. Increase the variability in the population D. Either A and B would be a good choice E. All of the above would be good choices

B. increase the sample size

17. A listing of all possible outcomes of a random variable along with the corresponding probabilities of occurrence is called a A. Random variable B. Probability distribution C. Population D. Sample E. None of the above

B. probability distribution

The difference between a population parameter and the sample statistic is... A. At the center of a normal distributions B. Sampling error C. Usually very large D. Usually very small E. None of the above

B. sampling error

44. When conducting a dependent sample, paired data test, the sample estimate is A. one of the sample means B. the mean of the differences C. the population mean D. the sample standard deviation

B. the mean of the differences

42. The power of a hypothesis test is A. its ability to answer a question about a population parameter B. the probability of rejecting the null hypothesis when the null is false C. that we can make inferences about a sample mean D. none of the above are correct E. A, B, and C are correct

B. the probability of rejecting the null hypothesis when the null is false

7. For data that have been ordered from smallest to largest values, where is the median located? A. n B. n/2 C. (n + 1)/2 D. n + 1/2 E. n + 2

C. (n+1)/2

40. What is the probability of making a Type II error if the null hypothesis is actually true? A. alpha B. 1 C. 0 D. 0.025 E. It is usually 0.05

C. 0

53. If all the data for a regression analysis are plotted on a scatter diagram...of estimate would be: a. -1 b. +1 c. 0 d. It cannot be determined from this information

C. 0

20. What is the area under the normal curve between z = 1.00 and z = 1.79? A. 0.4633 B. 0.79 C. 0.1220 D. 2.79 E. None of the above

C. 0.1220

15. The number of hours per semester worked for a sample of students follows: 139, 136, 131, 136, 147, 130, 135, 138, 139, and 142. What is the mode? A. 136 B. 139 C. 136 and 139 D. 130, 136, and 139 E. none of the above

C. 136 and 139

26. The mean number of travel days per year for salespeople employed by hardware distributors needs to be estimated with 95% confidence. For a small pilot study, the mean was 150 days and the standard deviation was 14 days. If the population mean is to be estimated within two days, how many salespeople should be sampled? A. 13.72 B. 14 C. 189 D. 150 E. unable to be determined from the information provided

C. 189

16. If the variance for a sample of hourly wages was computed to be $25, what is the standard deviation? A. $625 B. $25 C. $5 D. $50 E. Cannot be determined from the information provided

C. 5

8. The hours worked for a sample of employees are: 6, 0, 10, 14, 8, and 0, What is the median hours worked? A. 12 B. 6 C. 7 D. 8 E. There is no median for these data

C. 7

What is the value of the test statistic for #14 A. 3.027998 B. 1385.777 C. 9.842697 D. 0.000229 E. None of the above are right

C. 9.842697

19. For a normal distribution, the mean plus and minus 2 standard deviations will include about what percent observations? A. 50% B. 99.7% C. 95% D. 68% E. All of the observations

C. 95%

11. What level of measurement is needed in order to calculate the variance of a set of data? A. Discrete B. Ordinal C. Interval D. Ratio E. Continuous

C. Interval

What is the Null hypothesis for #14? A.B1=B2=B3=B4 B. B1 not equal to B2 not equal to B3 not equal to B4 C. M1=M2=M3=M4 D. M1 not equal to M2 not equal to M3 not equal to M4 E. None of the above are correct

C. M1=M2=M3=M4

22. When dividing a population into groups so that a random sample of the groups can be collected what type of sampling is used? A. Simple random sampling B. Systematic sampling C. Stratified random sampling D. Cluster sampling E. None of the above

C. Stratified random sampling

52. If the coefficient of correlation equals 0.40, then which of the following will... a. There is a strong relationship between the two variables b. 40% of the variation in one variable is explained by the other c. The coefficient of determination is 0.16 d. The coefficient of determination is .40

C. The coefficient of determination is 0.16

57. Larger values of r^2 imply that: a. The average of the independent variable in high b. Average value of the independent variable is low c. The regression line fits the data well d. The line passes through the origin

C. The regression line fits the data well

The null hypothesis is rejected for #25, the conclusion was A. There is a difference B. There is not a difference C. There is a positive relationship D. There is not a positive relationship

C. There is a positive relationship

45. A sample of 20 randomly selected students was given a multiple-choice test and an essay test on the same material and the scores were recorded for both rests for each of the 20 students. The professor was interested in determining which type of test would result in higher scores. This is an example of A. a one sample test of a population proportion B. a test for the difference between two population means C. a dependent samples (paired data, repeated measures) test D. a test of the difference between two population proportions E. none of the above is the appropriate test for this situation

C. a dependent samples (paired data, repeated measures) test

37. What information is needed to find a p-value? A. type of test and alpha level B. alpha level and test statistic C. type of test and test statistic D. type of test, alpha level, and test statistic

C. type of test and test statistic

14. The number of hours per semester worked for a sample of students follows: 139, 136, 131, 136, 147, 130, 135, 138, 139, and 142. What is the range? A. 10 B. 136 to 139 C. 130 to 147 D. 17 E. None of the above

D. 17

What is the value of the test statistic for #23 A. .874 B. .153 C. 10.488 D. 5.71 E. None of the above

D. 5.71

39. If the alternate hypothesis states that μ does not equal 4,000, where is the rejection region for the hypothesis test? A. Center of the distribution B. Lower or left tail of the distribution C. Upper or right tail of the distribution D. Both tails of the distribution

D. Both tails of the distribution

9. A disadvantage of using the mean to summarize a set of data is that the mean A. is not unique to a set of data B. can be used for interval and ratio data C. is always different form the median D. can be influenced by extreme values E. both A and D above are disadvantages

D. Can be influenced by extreme value

4. What type of variable is the number of auto accidents reported in a given month? A. Interval B. Ordinal C. Continuous D. Discrete E. None of the above

D. Discrete

What is the alternative hypothesis for #14? A.B1=B2=B3=B4 B. B1 not equal to B2 not equal to B3 not equal to B4 C. M1=M2=M3=M4 D. M1 not equal to M2 not equal to M3 not equal to M4 E. None of the above are correct

D. M1 not equal to M2 not equal to M3 not equal to M4

10. The mean, as a measure of central location would be inappropriate for which of the following? A. Ages of adults at a senior citizen center B. Weights of people residing in the state of Georgia C. Number of pages in textbooks on statistics D. Marital status of college students at a particular university E. It would be appropriate for all of the above

D. Marital status of college students at a particular university

2. Education was measured as Freshman, Sophomore, Junior, or Senior. What is the level of measures of a variable? A. Interval B. Ratio C. Nominal D. Ordinal E. Continuous

D. Ordinal

A large home improvement store interested in the relationship between and the amount of display space allotted to the fertilizer. The correlation... of 12 weeks was calculated to be .874 using Pearson correlation coefficient... hypothesis test to determine if there is a positive association between weekly... hypothesis would be? A. B1=B2 B. B1=0 C. B1 does not equal 0 D. P=0 E. P does not equal 0

D. P=0

1. Which of the following is NOT a use of descriptive statistics? A. Organizing B. Summarizing C. Presenting D. Predicting E. All of the above are uses

D. Predicting

5. Age is what level of measurement? A. Nominal B. Ordinal C. Interval D. Ratio E. Continuous

D. Ratio

25. The standard error is A. the standard deviation of the sample B. the standard deviation of the population C. the standard deviation of the population distribution D. the standard deviation of the sampling distribution E. both A and D are correct

D. The standard deviation of the sampling distribution

47. Regarding the ANOVA procedure; the appropriate situation for making inferences about...pairs of treatment means would be: a. When one way ANOVA design has been used b. When a two way ANOVA design has been used c. When the null hypotheses is has not been rejected d. When the null hypotheses has been rejected

D. When the null hypothesis has been rejected

58. In a simple regression analysis, if the Y intercept is positive, then: a. There is a positive relationship between X and Y b. If X is increased, Y must also increase c. If Y increased, X must also increase d. None of these alternatives is correct

D. none of these alternatives is correct

What is the alternative hypothesis for #23? A. B is greater than or equal to 0 B. B is greater than 0 C. B does not equal 0 D. P=0 E. P is greater than 0

E. P is greater than 0

How does variance measure dispersion?

It calculates distance from the mean

Why is the range not a satisfactory measure of dispersion?

It does not use enough data

55. Which of the following is true about the standard error of estimate? a. It is also called the coefficient of error b. Is it based on squared deviations between the actual Y values and actual X values c. It can be either negative or positive d. It is based on squared deviations between the actual Y values and predicted Y values

d. It is based on squared deviations between the actual Y values and predicted Y values

The sales manager of a company wants to determine if there is a different... manager randomly assigned trainees to four groups, and each group

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