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日期:2022-06-25 03:28:21

绪论

1、Penny Bauer, Chief Financial Officer of Harrison Haulage, suspects irregularities in the payroll system, and orders an inspection of ‘each and every payroll voucher issued since 1 January 2005’. Five per cent of the payroll vouchers contained material errors. This is an example of ________________.
    A、nonparametric statistics
    B、nominal data
    C、descriptive statistics
    D、inferential statistics

第一章测试

1、Michael Bayley, Marketing Director of UniPower’s Electrical Division, is leading a study to identify and assess the relative importance of product features. Michael directs his staff to design a survey questionnaire for distribution to all of UniPower’s 954 customers. For this study, the set of 954 customers is a ________________.
    A、statistic
    B、population
    C、parameter
    D、sample

2、Claudia Taylor, Director of Global Industrial Sales in Melbourne, is concerned by a deteriorating sales trend. Specifically, the number of customers is stable at 1500 but they are purchasing less each year. She orders her staff to search for causes of the downward trend by selecting a focus group of 40 industrial customers. For this study, the set of 40 industrial customers is a _______.
    A、statistic
    B、sample
    C、population
    D、parameter

3、A politician who is running for the office of premier in a state with 3 million registered voters commissions a survey. In the survey, 53.6% of the 5000 registered voters interviewed say they plan to vote for him. The population of interest is the
    A、3 million registered voters in the state.
    B、5000 registered voters interviewed.
    C、53.6 % of, or 2680, voters interviewed who plan to vote for him
    D、46.4% of, or 2320, voters interviewed who plan not to vote for him

4、Simon Arnett, Director of Human Resources, is exploring the causes of employee absenteeism at Buderim Bottling during the last operating year (1 January 2005 to 31 December 2005). The average number of absences per employee, calculated from the personnel data of all employees, is a ___________________.
    A、population
    B、sample
    C、parameter
    D、statistic

5、A summary measure that is computed from a sample to describe a characteristic of the population is called
    A、a parameter
    B、a statistic
    C、a population
    D、Both A and C are correct, since they are the same

6、Simon Arnett, Director of Human Resources, is exploring the causes of employee absenteeism at Buderim Bottling during the last operating year (1 January 2005 to 31 December 2005). Personnel records of 50 employees are selected for analysis. (The plant employs 250.) For this study, the average number days absent for these 50 employees is a ________________.
    A、population
    B、sample
    C、parameter
    D、statistic

7、Descriptive statistics deals with methods of
    A、organising data.
    B、summarising data
    C、presenting data in a convenient and informative way
    D、doing all of the above

8、Which of the following statements is not true?
    A、One form of descriptive statistics uses graphical techniques
    B、One form of descriptive statistics uses numerical techniques
    C、In the language of statistics, the term population refers to a group of people
    D、Statistical inference is used to draw conclusions or inferences about characteristics of populations based on sample data

9、A student achieves an 82 on the first test in a statistics course. From this, she assumes that her average at the end of the semester (after other tests) will be about 82. This is an example of ___________________.
    A、descriptive statistics
    B、inferential statistics
    C、nonparametric statistics
    D、wishful thinking

10、Which of the following is not the goal of descriptive statistics?
    A、Summarising data
    B、Displaying aspects of the collected data
    C、Reporting numerical findings
    D、Estimating characteristics of the population

第二章测试

1、If data are grouped into intervals and the number of items in each group is listed, this could be called a _______________.
    A、ogive
    B、histogram
    C、frequency distribution
    D、stem and leaf plot

2、If the individual class frequency is divided by the total frequency, the result is the __________.
    A、midpoint frequency
    B、cumulative frequency
    C、stem and leaf plot
    D、relative frequency

3、A cumulative frequency polygon is also called _______________.
    A、an ogive
    B、a histogram
    C、a frequency polygon
    D、a stem and leaf plot

4、The number of class intervals in a frequency distribution is usually between ___________.
    A、3 and 5
    B、7 and 9
    C、5 and 15
    D、1 and 25

5、One advantage of a stem and leaf plot over a frequency distribution is that __________.
    A、it contains more class intervals
    B、the values of the original data are retained
    C、the class midpoints are used as the stem
    D、the class midpoints are used as the leaf

6、One rule that must always be followed in constructing frequency distributions is that ________.
    A、the number of classes must be less than 10
    B、each data point can only fall into one class
    C、the width of each class is equal to the range
    D、the number of intervals must be an odd number

7、Which of the following is best to show the percentage of a total budget that is spent on each category of items?
    A、histogram
    B、ogive
    C、stem and leaf chart
    D、pie chart

8、A cumulative frequency distribution would provide _____________.
    A、a graph of a frequency distribution
    B、a running total of the frequencies in the classes
    C、the proportion of the total frequencies which fall into each class
    D、a very cloudy picture of the frequencies

9、The number of phone calls arriving at a switchboard each hour has been recorded and the following frequency distribution has been developed. Class Interval Frequency 20-under 40 30 40-under 60 45 60-under 80 80 80-under 100 45 What is the cumulative frequency of the third class?
    A、80
    B、0.40
    C、155
    D、75

10、The number of phone calls arriving at a switchboard each hour has been recorded and the following frequency distribution has been developed. Class Interval Frequency 20-under 40 30 40-under 60 45 60-under 80 80 80-under 100 45 What is the approximate range of the number of phone calls arriving each hour?
    A、80
    B、200
    C、20
    D、100

第三章测试

1、Simon Arnett, Director of Human Resources, is exploring employee absenteeism at the Buderim Bottling during the last operating year. A sample of six personnel records produced the following data: 0, 2, 4, 7, 2, 9. The variance of the number absences per employee is ____________.
    A、11.6
    B、9.67
    C、3.41
    D、3.11

2、Jessica Salas, Managing Director of Salas Products, is reviewing the warranty policy for her company’s new model of car batteries. Life tests performed on a sample of 100 batteries indicated: (1) an average life of 75 months, (2) a standard deviation of 5 months, and (3) battery life is approximately normally distributed. Approximately 68% of the batteries will last between ________________.
    A、70 and 80 months
    B、60 and 90 months
    C、65 and 85 months
    D、55 and 95 months

3、The average starting salary for graduates at a university is $25,000 with a standard deviation of $2000. A histogram of the data shows the shape to be very erratic so Chebyshev’s Theorem should be used. How many of the graduates would have a starting salary between 21,000 and 29,000?
    A、at least 75%
    B、at least 89%
    C、at least 68%
    D、at least 95%

4、The sample standard deviation is found by taking the square root of _______.
    A、the sample mean
    B、the sample variance
    C、the coefficient of variation
    D、the mean absolute deviation

5、The number of standard deviations that a value (X) is above or below the mean is the _______.
    A、absolute deviation
    B、coefficient of variation
    C、interquartile range
    D、Z score

6、In a histogram, the proportion of the total area that must be to the left of the median is( )
    A、exactly 0.50.
    B、less than 0.50 if the distribution is skewed to the left
    C、more than 0.50 if the distribution is skewed to the right
    D、between 0.25 and 0.60 if the distribution is symmetric and unimodal

7、Which of the following is NOT a measure of central tendency?
    A、mean
    B、median
    C、variance
    D、mode

8、Another term for average is ____________.
    A、mode
    B、mean
    C、median
    D、variance

9、If the mean of a distribution is greater than the median, then the distribution is ____________.
    A、not skewed
    B、symmetrical about its mean
    C、skewed to the left
    D、skewed to the right

10、The mean is not affected by the extreme values.

第四章测试

1、A process that produces outcomes is called _______.
    A、an event
    B、an experiment
    C、a result
    D、population equivalent

2、Which of the following is NOT a legitimate probability value?
    A、0.67
    B、15/16
    C、0.23
    D、4/3

3、An outcome of an experiment is called _______.
    A、an event
    B、a priori elements
    C、a probability
    D、a complement

4、The list of all elementary events for an experiment is called _______.
    A、the sample space
    B、the exhaustive list
    C、the population space
    D、the event union

5、If A and B are mutually exclusive events with P(A) = 0.70, then P(B):( )
    A、can take any value between 0 and 1
    B、can take any value between 0 and 0.70
    C、cannot be larger than 0.30
    D、cannot be determined from the information given

6、If an event is in set X but is not in set Y, which of the following is true?
    A、it is not in the union of X and Y
    B、it is in the union of X and Y
    C、it is in the intersection of X and Y
    D、it is in both the union and intersection of X and Y

7、If the occurrence of one event does not affect the occurrence of another event, then the two events are _______.
    A、mutually exclusive
    B、complements
    C、independent
    D、elementary events

8、Let A be the event that a student is enrolled in an accounting course, and let S be the event that a student is enrolled in a statistics course. It is known that 30% of all students are enrolled in an accounting course and 40% of all students are enrolled in statistics. Included in these numbers are 15% who are enrolled in both statistics and accounting. Find P(S).
    A、0.15
    B、0.30
    C、0.40
    D、0.55

9、Given P(A) = 0.40, P(B) = 0.50, P(A B) = 0.15. Which of the following is true?
    A、A and B are independent
    B、A and B are mutually exclusive
    C、A and B are collectively exhaustive
    D、A and B are not independent

10、Meagan Davies manages a portfolio of 200 common stocks. Her staff classified the portfolio stocks by ‘industry sector’ and ‘investment objective’. Investment Industry Sector Objective Electronics Airlines Healthcare Total Growth 100 10 40 150 Income 20 20 10 50 Total 120 30 50 200 Which of the following is NOT true?
    A、Growth and Income are complementary events.
    B、Electronics and Growth are dependent.
    C、Electronics and Healthcare are mutually exclusive.
    D、Airlines and Healthcare are collectively exhaustive.

第五章测试

1、Variables which take on values only at certain points over a given interval are called _______.
    A、point variables
    B、continuous random variables
    C、discrete random variables
    D、value variables

2、A variable that can take on values at any point over a given interval is called _______.
    A、a point variable
    B、a continuous random variable
    C、a discrete random variable
    D、a value variable

3、You are offered an investment opportunity. Its outcomes and probabilities are presented in the following table. X P(X) –$1000 .40 $0 .20 +$1000 .40 The mean of this distribution is _____________.
    A、–$400
    B、$0
    C、$200
    D、$400

4、You are offered an investment opportunity. Its outcomes and probabilities are presented in the following table. X P(X) –$1000 .40 $0 .20 +$1000 .40 The standard deviation of this distribution is _____________.
    A、–$400
    B、$663
    C、$800,000
    D、$894

5、The long-run average or mean of a Poisson distribution is usually referred to as _______.
    A、m
    B、s
    C、l
    D、a

6、The variance of a Poisson distribution is equal to _______.
    A、l
    B、l/2
    C、l2
    D、1566196840(1).jpg

7、If X is a binomial random with n = 8 and p = 0.6, what is the probability that X is less than or equal to 2?
    A、0.050
    B、0.009
    C、0.041
    D、0.375

8、If X is a binomial random with n = 8 and p = 0.6, what is the probability that X is greater than 2?
    A、0.124
    B、0.991
    C、0.950
    D、0.011

9、Twenty-five items are sampled. Each of these has the same probability of being defective. The probability that exactly 2 of the 25 are defective could best be found by _______.
    A、using the normal distribution
    B、using the binomial distribution
    C、using the Poisson distribution
    D、using the exponential distribution

10、You are offered an investment opportunity. Its outcomes and probabilities are presented in the following table. X P(X) –$1000 .40 $0 .20 +$1000 .40 Which of the following statements is true?
    A、This distribution is skewed to the right.
    B、This is a binomial distribution.
    C、This distribution is symmetric.
    D、This distribution is skewed to the left.

第六章测试

1、The normal distribution is an example of _______.
    A、a discrete distribution
    B、a continuous distribution
    C、a bimodal distribution
    D、an exponential distribution

2、The total area underneath any normal curve is _______.
    A、equal to the mean
    B、equal to 1
    C、equal to the variance
    D、equal to the coefficient of variation

3、The area to the left of the mean in any normal distribution is _______.
    A、equal to the mean
    B、equal to 1
    C、equal to the variance
    D、equal to 0.5

4、For any normal distribution, any value less than the mean would have a _______.
    A、positive z-score
    B、negative z-score
    C、negative variance
    D、negative probability of occurring

5、A standardised normal distribution has the following characteristics:
    A、he mean and variance are both equal to 1
    B、the mean and variance are both equal to 0
    C、the mean is equal to the variance
    D、the mean is equal to 0 and the variance is equal to 1

6、If X is a normal random variable with mean 80 and standard deviation 5, calculate the z-score if X = 88.
    A、1.8
    B、-1.8
    C、1.6
    D、-1.6

7、Suppose X is a normal random variable with mean 60 and standard deviation 2. A z-score was calculated for a number, and the z-score is 3.4. What is x?
    A、63.4
    B、56.6
    C、66.8
    D、53.2

8、Let X be a normal random variable with mean 20 and standard deviation 4. Find P(16 < X < 22).
    A、0.4672
    B、0.0328
    C、0.1498
    D、0.5328

9、Let X be a normal random variable with mean 20 and standard deviation 4. The 90th percentile of X is ____________.
    A、25.126
    B、20.000
    C、22.698
    D、26.579

10、A z-score is the number of __________ that a value is from the mean.
    A、variances
    B、standard deviations
    C、units
    D、miles

第七章测试

1、As a general rule, the normal distribution is used to approximate the sampling distribution of the sample mean only if
    A、the sample size n is sufficiently large
    B、the sample mean is close to 0.50.
    C、the underlying population is normal
    D、np and n(1 – p) are both greater than 5

2、The eight employees of the Art Department and their ‘years of experience’ are listed in the following table. Employee A B C D E F G H Experience (years) 10 2 1 1 15 7 4 8 If a sample of three employees is selected with replacement, the number of elementary outcomes in the sample space is _______________.
    A、56
    B、64
    C、336
    D、512

3、A sampling distribution is a distribution of _______________.
    A、excess profits to selected shareholders.
    B、a sample statistic, such as,图片11.png
    C、a population parameter, such as, µ.
    D、a population attribute, such as, employee’s age.

4、The standard deviation of a sampling distribution is commonly called _______.
    A、statistical leverage.
    B、the uniform spread.
    C、statistical margin.
    D、the standard error.

5、The central limit theorem states that if n is large enough, the distribution of the sample means is _____________ distributed regardless of the shape of the population.
    A、approximately normally
    B、uniformly
    C、randomly
    D、nonrandomly

6、According to the central limit theorem, the mean of the sample means for a given size of sample is equal to _______.
    A、the population mean divided by n
    B、the population mean
    C、the population mean divided by the square root of n
    D、zero

7、Increasing the sample size causes the standard error of the mean to ________.
    A、destabilise in value
    B、decrease in value
    C、seek market equilibrium
    D、increase in value

8、Increasing the sample size causes the sampling distribution of 图片11.png to ________.
    A、shift to the right
    B、shift to the left
    C、have more dispersion
    D、have less dispersion

9、Suppose a population has a mean of 90 and a standard deviation of 28. If a random sample of size 49 is drawn from the population, the probability of drawing a sample with a mean of more than 95 is _______.
    A、0.1056
    B、0.3944
    C、0.4286
    D、0.8944

10、Suppose 40% of all university students have a computer at home and a sample of 64 is taken. What is the probability that more than 30 of those in the sample have a computer at home?
    A、0.3686
    B、0.1314
    C、0.8686
    D、0.6314

第八章测试

1、When a range of values is used to estimate a population parameter, it is called _______.
    A、an interval estimate
    B、a point estimate
    C、a statistical parameter
    D、a range estimate

2、Catherine Cho, Director of Marketing Research at Vitalglow Pty Ltd, is evaluating consumer acceptance of a new toothpaste package. Her staff report that 17% of a random sample of 200 Darwin households prefer the new package to all other package designs. If Catherine concludes that 17% of all households prefer the new package, she is using a _______.
    A、a point estimate
    B、a range estimate
    C、a statistical parameter
    D、an interval estimate

3、The z-value associated with a two-sided 90% confidence interval is _______.
    A、1.28
    B、1.645
    C、1.96
    D、2.575

4、Suppose a random sample of 36 is selected from a population with a standard deviation of 12. If the sample mean is 98, the 99% confidence interval to estimate the population mean is _______.
    A、94.08 to 101.92
    B、92.85 to 103.15
    C、97.35 to 98.65
    D、93.34 to 102.66

5、Sam Gates, Marketing Director of Mansfield Motors’ Electrical Division, is leading a study to assess the relative importance of product features. An item on a survey questionnaire distributed to 121 Mansfield customers asked them to rate the importance of ‘ease of maintenance’ on a scale of 1 to 10 (with 1 meaning ‘not important’ and 10 meaning ‘highly important’). His staff assembled the following statistics. Ease of Maintenance Mean 7.5 Population Standard Deviation 1.1 The 90% confidence interval for the population mean rating of ‘ease of maintenance’ is _____.
    A、5.34 to 9.66
    B、7.34 to 7.66
    C、5.69 to 9.31
    D、7.30 to 7.70

6、A researcher wants to estimate the proportion of the population which possess a given characteristic. A random sample of size 600 is taken resulting in 330 items which possess the characteristic. The point estimate for this population proportion is _______.
    A、0.55
    B、0.33
    C、0.60
    D、0.45

7、The t-distribution is similar to a normal distribution. However the t-distribution is _______.
    A、not symmetric
    B、bimodal
    C、flatter
    D、discrete

8、In order to find values in the t- distribution table, you must convert the sample size or sizes to _______.
    A、population sizes
    B、degrees of freedom
    C、z-values
    D、student values

9、If the degrees of freedom in a t-distribution become very large, _______.
    A、the t-values and the z-values are almost the same
    B、the sample size must be very small
    C、the population size must be very large
    D、the sample mean approaches zero

10、In finding a confidence interval for the population mean, the population standard deviation should be used if it is known. If the population standard deviation is not known, then it should be estimated with _______.
    A、the sample variance
    B、the sample standard deviation
    C、the range
    D、the mean

第九章测试

1、The first step in testing a hypothesis is to establish _______.
    A、a not rejectance hypothesis and a rejection hypothesis
    B、a power function
    C、a null hypothesis and alternative hypothesis
    D、an indirect hypothesis

2、Consider the following null and alternative hypotheses. Ho: m <=7 Ha: m > 6 These hypotheses _______________.
    A、are not mutually exclusive
    B、are not collectively exhaustive
    C、do not reference a population parameter
    D、are established correctly

3、Consider the following null and alternative hypotheses. Ho: m >= 7 Ha: m < 6 These hypotheses _______________.
    A、are not mutually exclusive
    B、are not collectively exhaustive
    C、do not reference a population parameter
    D、are established correctly

4、Consider the following null and alternative hypotheses. Ho: 图片11.png£ 352 Ha: 图片11.png > 352 These hypotheses _______________.
    A、are not mutually exclusive
    B、are not collectively exhaustive
    C、do not reference a population parameter
    D、are established correctly

5、The region of the distribution in hypothesis testing in which the null hypothesis is rejected is called the _______.
    A、not rejectance region
    B、null region
    C、alternative region
    D、rejection region

6、The rejection and not rejectance regions are divided by a point called the _______.
    A、dividing point
    B、critical value
    C、rejection value
    D、not rejectance value

7、The probability of committing a Type II error is represented by _______.
    A、a
    B、b
    C、1 – a
    D、a / 2

8、Jennifer Cantu, Customer Services Manager at Tri-Nation Auto Insurance, monitors the claims processing time of the claims division. Her standard includes ‘a mean processing time of 5 days or less’. Each week, her staff checks for compliance by analysing a random sample of 60 claims. Jennifer’s alternative hypothesis is ________.
    A、> 5
    B、5
    C、n = 60
    D、< 5

9、The manufacturers of a deodorant claim that the mean drying time of their product is, at most, 15 minutes. A sample consisting of 16 cans of the product was used to test the manufacturer’s claim. The experiment yielded a mean drying time of 18 minutes with a standard deviation of 6 minutes. Test the claim at the 0.05 significance level.
    A、Computed test statistic = 2 and is greater than 1.645, so reject H0: µ ≤ 15.
    B、Computed test statistic = 2 and is greater than 1.96, so reject H0: µ ≤ 15.
    C、Computed test statistic = 2 and is greater than 1.753, so reject H0: µ = 15.
    D、Computed test statistic = 2 and is greater than 2.131, so reject H0: µ ≤ 15.

10、What happens to the rejection region if the level of significance is changed from 0.10 to 0.05?
    A、it gets larger
    B、it gets smaller
    C、it does not change

第十章测试

1、Restaurateur, Daniel Valentine, is evaluating two sites, Port Douglas and Mission Beach, for his next restaurant. He wants to prove that Port Douglas residents (population 1) dine out more often than Mission Beach residents (population 2). Denny plans to test this hypothesis using a random sample of 81 families from each town. His null hypothesis is __________.
    A、s12 < s22
    B、m1 – m2 > 0
    C、p1 – p2 = 0
    D、m1 ≤m2

2、A researcher wants to estimate the difference in the means of two populations. A random sample of 36 items from the first population results in a sample mean of 430. A random sample of 49 items from the second population results in a sample mean of 460. The population standard deviations are 120 for the first population and 140 for the second population. From this information, a point estimate of the difference of population means can be calculated as _______.
    A、-30
    B、46
    C、43
    D、-13

3、A researcher wants to estimate the difference in the means of two populations. A random sample of 36 items from the first population results in a sample mean of 430. A random sample of 49 items from the second population results in a sample mean of 460. The population standard deviations are 120 for the first population and 140 for the second population. From this information, a 95% confidence interval for the difference in population means is _______.
    A、–95.90 to 35.90
    B、85.44 to 25.44
    C、–76.53 to 16.53
    D、–102.83 to 42.43

4、A researcher is interested in testing to determine if the mean of population one is greater than the mean of population two. The null hypothesis is that there is no difference in the population means (i.e. the difference is zero). The alternative hypothesis is that there is a difference (i.e. the difference is not equal to zero). He randomly selects a sample of 9 items from population one resulting in a mean of 14.3 and a standard deviation of 3.4. He randomly selects a sample of 14 items from population two resulting in a mean of 11.8 and a standard deviation 2.9. He is using an alpha value of .10 to conduct this test. Assuming that the populations are normally distributed, the degrees of freedom for this problem are _______.
    A、23
    B、22
    C、15
    D、2

5、A researcher wants to conduct a before/after study on 11 subjects to determine if a treatment results in any difference in scores. The null hypothesis is that the average difference is zero while the alternative hypothesis is that the average difference is not zero. Scores are obtained on the subjects both before and after the treatment. After subtracting the after scores from the before scores, the average difference is calculated to be –2.40 with a sample standard deviation of 1.21. Assume that the differences are normally distributed in the population. The degrees of freedom for this test are _______.
    A、11
    B、10
    C、9
    D、20

6、A researcher is performing a two-tailed related samples (matched pairs) t-test. A total of 12 people are in the sample, and before and after measures are taken. The observed t-value for this is –1.84. The level of significance is 0.05. The correct decision is to _______.
    A、do not reject the null hypothesis
    B、reject the null hypothesis
    C、take a larger sample
    D、use the z-table instead of the t-table

7、Stefan Irwin, Marketing Manager at Classic Merchandise, is investigating response rates to scented and unscented direct mail catalogues. If the response rate for the scented catalogue (population 1) is higher, Mike will adopt the scented version. His staff randomly selects two samples of 200 each from the company’s customer database. One month after the 400 test catalogues were mailed, forty-five orders (twenty-five from the scented and twenty from the unscented) were received from the test catalogues. Assuming a = .01, Mike’s alternate hypothesis is ________________.
    A、p1 – p2 > 0
    B、m1 – m2 = 0
    C、m1 – μ2 ≠ 0
    D、s12 < s22

8、Cowra Construction Company purchases steel rods for its projects. Based on previous tests, Clarrie Carter, Quality Assurance Manager, has recommended purchasing rods from Redding Rods (population 1), rather than Stockton Steel (population 2), since Redding’s rods had less variability in length. Recently, Stockton revised it rod shearing operation, and Clarrie has sampled the outputs from Redding’s and Stockton’s rod manufacturing processes. The results for Redding were s12 = 0.10 with n1 = 8, and, for Stockton, the results were s22 = 0.05 with n2 = 10. Assume that rod lengths are normally distributed in the population. Clarrie’s alternate hypothesis is __________________.
    A、s12 = s22
    B、s12 ≠ s22
    C、s12 > s22
    D、s12 < s22

9、Tamara Hill, Fund Manager with Hillcrest Value Fund, manages a portfolio of 250 common stocks. Tamara is searching for a ‘low risk’ issue to add to the portfolio, i.e. one with a price variance less than that of the S&P 500 index. Moreover, she assumes an issue is not ‘low risk’ until demonstrated otherwise. Her staff reported that during the last nine quarters the price variance for the S&P 500 index (population 1) was 25, and for the last seven quarters the price variance for XYC common (population 2) was 8. Assume that stock prices are normally distributed in the population. Using a = 0.05, the appropriate decision is _______.
    A、reject the null hypothesis s12 = s22
    B、eject the null hypothesis s12 ¹ s22
    C、do not reject the null hypothesis s12 = s22
    D、do not reject the null hypothesis s12 ¹ s22

10、Cindy Ho, Finance Manager at Red Hill Radiator Supplies (RHRS), theorises that the discount level offered to credit customers affects the average collection period on credit sales. Accordingly, she has designed an experiment to test her theory using four sales discount rates (0%, 2%, 4% and 6%) by randomly assigning five customers to each sales discount rate. An analysis of Cindy’s data produced the following ANOVA table. Source of Variation SS df MS F Treatment 5.35 3 1.783333 Error 177.2 16 11.075 Total 182.55 19 Using a = 0.01, the appropriate decision is _________.
    A、reject the null hypothesis m1 = m2 = m3 = m4
    B、reject the null hypothesis m1 ≠ m2 ≠ m3 ≠ m4
    C、do not reject the null hypothesis m1 = m2 = m3 = m4
    D、do not reject the null hypothesis m1 ≠ m2 ≠ m3 ≠m4

第十一章测试

1、For the same set of observations on a specified dependent variable, two different independent variables were used to develop 2 simple linear regression models. The results are summarized as follows: 图片1.png Based on the above results, we can conclude that
    A、a prediction based on Model I is likely better than a prediction based on Model II.
    B、a prediction based on Model II is likely better than a prediction based on Model I.
    C、the SSE for Model II is smaller than the SSE for Model I.
    D、the total variation is different for Model I and Model II.

2、A regression analysis between sales (in $1000) and advertising (in $100) yielded the least squares line 图片2.png= 75 + 6x. This implies that if $800 is spent on advertising, then the predicted amount of sales (in dollars) is
    A、$12,300
    B、$123,000
    C、$4,875
    D、$487,500

3、The following results were obtained from a simple regression analysis: 图片2.png= 37.2895 – 1.2024x r2 = 0.6744 and s2 = 0.2934 For each unit change in x, the estimated change in the average value of y is equal to
    A、37.289
    B、-1.2024
    C、0.6744
    D、0.2934

4、A regression analysis between sales (in $1,000) and advertising (in $) yielded the least square line 图片2.png= 80,000 + 5x This implies that an
    A、increase of $1 in advertising is expected to result in an increase of $5 in sales.
    B、increase of $5 in advertising is expected to result in an increase of $5,000 in sales.
    C、increase of $1 in advertising is expected to result in an increase of $80,005 in sales.
    D、increase of $1 in advertising is expected to result in an increase of $5,000 in sales.

5、The point estimate of the variance of the error term in a regression model is
    A、MSE
    B、SSE
    C、图片3.png
    D、图片4.png

6、In a regression problem, if the coefficient of determination is 0.95, this means that:
    A、95% of the y values are positive.
    B、95% of the variation in y can be explained by the variation in x.
    C、95% of the x values are equal.
    D、95% of the variation in x can be explained by the variation in y.

7、In regression analysis, the residuals represent the:
    A、difference between the actual y values and their predicted values.
    B、difference between the actual x values and their predicted values.
    C、square root of the coefficient of determination.
    D、change in y per unit change in x.

8、In the simple linear regression model, the population parameters of the y-intercept and the slope are estimated by:
    A、 and
    B、 and
    C、 and 图片6.png
    D、 and

9、If the standard error of estimate 图片9.png = 20 and n = 10, then the sum of squares for error, SSE, is:
    A、400
    B、3200
    C、4000
    D、40,000

10、Which of the following statistics and procedures can be used to determine whether a linear model should be employed?
    A、The standard error of estimate.
    B、The coefficient of determination.
    C、The t-test of the slope.
    D、All of the above are correct answers.