Statistics for Economists
Exam Answer Key
Course Introduction
Statistics for Economists introduces students to fundamental statistical concepts and methods essential for economic analysis. The course covers descriptive statistics, probability theory, sampling distributions, estimation, hypothesis testing, regression analysis, and interpretation of economic data. Emphasis is placed on applying statistical techniques to real-world economic problems, enabling students to analyze data, test economic theories, and make informed decisions. Students will also gain familiarity with statistical software, enhancing their ability to handle, visualize, and interpret large data sets in an economic context.
Recommended Textbook
Statistics for Business and Economics 8th Edition by Betty Newbold
Available Study Resources on Quizplus
17 Chapters
3406 Verified Questions
3406 Flashcards
Source URL: https://quizplus.com/study-set/2018
Page 2
Chapter 1: Describing Data: Graphical
Available Study Resources on Quizplus for this Chatper
247 Verified Questions
247 Flashcards
Source URL: https://quizplus.com/quiz/40148
Sample Questions
Q1) An example of a quantitative variable is the make of a car.
A)True
B)False
Answer: False
Q2) It is possible to use statistics to quantify the relationship between variables.
A)True
B)False
Answer: True
Q3) By selecting a particular scale of measurement,the researcher can,in a time-series plot,create an impression either of relative stability or of substantial fluctuation over time.
A)True
B)False
Answer: True
Q4) A cable company,based on a survey of its customers,reports that 48% of all the television audience watch Larry King Live daily.Is this an example of descriptive or inferential statistics?
Answer: Inferential statistics
Q5) Describe the population.
Answer: All boxes of pencils in the warehouse
Page 3
To view all questions and flashcards with answers, click on the resource link above.
Chapter 2: Describing Data: Numerical
Available Study Resources on Quizplus for this Chatper
326 Verified Questions
326 Flashcards
Source URL: https://quizplus.com/quiz/40149
Sample Questions
Q1) Describe the shape of the distribution of the number of trades per month for these 10 clients.Justify your answer.
Answer: The distribution is skewed to the right (or positively skewed)since mean = 6.35 > median = 5.9.
Q2) What are the three data values such that the new sample has a mean of 100? Justify your answer.
Answer: Many different answers are possible.The sum of the five numbers needs to be 500;therefore we need any three numbers that total 330,such as 110.110.110 or as 100,110,120.Thus,the new sample mean 11ea5b8a_b6d3_ce5d_b1f3_a1d3ad286c26_TB2968_11 = 500/5 = 100.
Q3) A bored carpenter counts the actual number of nails in 10 boxes of nails and records his findings as: 230,235,302,287,312,323,265,319,342,and 298.What can we say about the shape of the distribution of the number of nails?
A)symmetric
B)skewed to the right
C)approximately bell-shaped
D)skewed to the left
Answer: D
To view all questions and flashcards with answers, click on the resource link above.
4
Chapter 3: Probability
Available Study Resources on Quizplus for this Chatper
345 Verified Questions
345 Flashcards
Source URL: https://quizplus.com/quiz/40150
Sample Questions
Q1) Calculate P(A<sub>1</sub> A<sub>2</sub>).
Answer: P(A<sub>1</sub> A<sub>2</sub>)= P(A<sub>1</sub> A<sub>2</sub>)/ P(A<sub>2</sub>)= 0 / 0.40 = 0
Q2) To determine the effectiveness of a new advertisement which is shown to one customer group and not another,followed by observation of the purchase behavior of both groups is determined by the use of:
A)odds.
B)marginal probabilities.
C)overinvolvement ratios.
D)tree diagrams.
Answer: C
Q3) What is the probability of the intersection of events A and B? Why?
Answer: P(A B)= 0,since A and B are mutually exclusive events.
Q4) A subset of the basic outcomes is classified as a sample.
A)True
B)False
Answer: False
Q5) Are events A and B collectively exhaustive? Why?
Answer: No,since (A B)<sub> </sub>The sample space S.
To view all questions and flashcards with answers, click on the resource link above. Page 5
Chapter 4: Discrete Random Variables and Probability
Distributions
Available Study Resources on Quizplus for this Chatper
257 Verified Questions
257 Flashcards
Source URL: https://quizplus.com/quiz/40151
Sample Questions
Q1) Calculate E(XY).
Q2) The Poisson distribution is applied to events for which the probability of occurrence over a given span of time,space,or distance is very small.
A)True
B)False
Q3) Any discrete distribution is applicable when the events of interest occur randomly,independently of one another,and rarely.
A)True
B)False
Q4) Are X and Y independent? Explain.
Q5) On the average,2.4 customers per minute arrive at any one of the checkout counters of a grocery store.A hypergeometric distribution can be used to find out the probability that there will be no customers arriving at a checkout counter.
A)True
B)False
Q6) Identify the covariance between X and Y.
Q7) What is P(X 2)?
6
Q8) Interpret the correlation coefficient found in the previous question.
To view all questions and flashcards with answers, click on the resource link above.
Chapter 5: Continuous Random Variables and Probability
Distributions
Available Study Resources on Quizplus for this Chatper
239 Verified Questions
239 Flashcards
Source URL: https://quizplus.com/quiz/40152
Sample Questions
Q1) Given a normal random variable X with mean of 70 and standard deviation of 12,the value of the standard normal random variable Z associated with X = 82 is larger than zero.
A)True
B)False
Q2) To obtain the probability that a continuous random variable falls in a specified range,we find the difference between the cumulative probabilities at the lower and upper end of the:
A)range.
B)median.
C)mode.
D)mean.
Q3) Let the random variable Z follow a standard normal distribution,and let z<sub>1</sub> be a possible value of Z that is unknown but identifiable by position and area.Find z<sub>1</sub> if the area to the right of z<sub>1</sub> is 0.8413.
A)1.00
B)-1.00
C)0.00
D)0.41
To view all questions and flashcards with answers, click on the resource link above. Page 7
Chapter 6: Sampling and Sampling Distributions
Available Study Resources on Quizplus for this Chatper
147 Verified Questions
147 Flashcards
Source URL: https://quizplus.com/quiz/40153
Sample Questions
Q1) The probability is 90% that the sample variance is less than what percent of the population variance?
Q2) A basketball player shoots 60 free throws a day and historically makes 75 percent of them.What is the probability that he will make at most 80 percent tomorrow?
A)0.1056
B)0.8133
C)0.1867
D)0.8944
Q3) The results of a recent survey indicated that 17.7% of all U.S.adults had taken a commercial airplane flight during the last year.If we take a random sample of 200 adults,what is the probability that more than 20% flew during the past year?
Q4) As the size of the sample increases,what happens to the shape of the sampling distribution of sample means?
A)It becomes positively skewed.
B)It becomes negatively skewed.
C)It becomes uniformly distributed.
D)It becomes approximately normal.
Q5) What is the probability that the sample proportion is between 0.78 and 0.84?
To view all questions and flashcards with answers, click on the resource link above. Page 8
Chapter 7: Estimation: Single Population
Available Study Resources on Quizplus for this Chatper
151 Verified Questions
151 Flashcards
Source URL: https://quizplus.com/quiz/40154
Sample Questions
Q1) What level of confidence is associated with an interval of $58.62 to $68.52 for the population mean daily spending?
Q2) A sample statistic such that the mean of all its possible values equals the population parameter the statistic seeks to estimate is an unbiased estimator.
A)True
B)False
Q3) An unbiased estimator of a population parameter is an estimator whose variance is the same as the actual value of the population variance.
A)True
B)False
Q4) Calculate the margin of error of the 95% confidence interval.
A)5.69
B)8.93
C)6.79
D)8.06
Q5) Assume that the population standard deviation is known to be 0.16.Calculate a 95% confidence interval for the population mean using the z table.
Q6) Develop a 90% confidence interval estimate for the population mean.
To view all questions and flashcards with answers, click on the resource link above. Page 9
Chapter 8: Estimation: Additional Topics
Available Study Resources on Quizplus for this Chatper
109 Verified Questions
109 Flashcards
Source URL: https://quizplus.com/quiz/40155
Sample Questions
Q1) Find the width of the 98% confidence interval.
A)5.46
B)3.64
C)0.91
D)0.60
Q2) What is the lower confidence limit of the 95% confidence interval?
A)-2.82
B)-3.88
C)2.45
D)3.88
Q3) Find the margin of error for a 99% confidence interval for the difference between the means of the two populations.
Q4) What is the upper confidence limit of the 98% confidence interval for the difference in population proportions?
A)-0.0151
B)0.004
C)0.007
D)0.025
Q5) Find the 95% confidence interval for the difference in the means of the two populations.
To view all questions and flashcards with answers, click on the resource link above. Page 10
Chapter 9: Hypothesis Testing: Single Population
Available Study Resources on Quizplus for this Chatper
164 Verified Questions
164 Flashcards
Source URL: https://quizplus.com/quiz/40156
Sample Questions
Q1) Suppose that a t test of H<sub>0</sub> : = 250 against H<sub>1</sub> : > 250 is based on 10 degrees of freedom.If the calculated value of the test statistic is t = 2.228,then the p-value for this test is 0.025.
A)True
B)False
Q2) The farther the true mean is from the hypothesized mean,the greater is the power of the test,everything else being equal.
A)True
B)False
Q3) A null hypothesis is rejected at the 0.025 level,but is not rejected at the 0.01 level.This means that the p-value of the test is between 0.01 and 0.025.
A)True
B)False
Q4) A random sample of 250 business faculty members was asked if there should be a required foreign language course for international business majors.Of these sample members,170 felt there was a need for a foreign language course.Test the hypothesis that at least 75% of all business faculty members hold this view.Use = 0.05.
To view all questions and flashcards with answers, click on the resource link above. Page 11
Chapter 10: Hypothesis Testing: Additional Topics
Available Study Resources on Quizplus for this Chatper
103 Verified Questions
103 Flashcards
Source URL: https://quizplus.com/quiz/40157
Sample Questions
Q1) Hypothesis tests that use the F distribution do not depend on the assumption that the populations are normally distributed as long as the sample sizes are large.
A)True
B)False
Q2) If the null hypothesis H<sub>0</sub> : <sub>x</sub> - <sub>y</sub> 0 is rejected against the alternative H<sub>1</sub> : <sub>x</sub> - <sub>y</sub> < 0 at the 2% level of significance,then using the same data,it must be rejected against that alternative at the 3% level.
A)True
B)False
Q3) What is the test statistic?
Q4) If testing for the difference between the means of two related populations,the appropriate null hypothesis is:
A)H<sub>0</sub> : <sub>D</sub><sub> </sub> 0
B)H<sub>0</sub> : <sub>D</sub> = 0
C)H<sub>0</sub> : <sub>D</sub> < 0
D)H<sub>0</sub> : <sub>D</sub> > 0
Q5) Calculate an estimate of the common proportion.
Q6) Use Excel or Minitab to conduct a two-sample t-test.
Page 12
To view all questions and flashcards with answers, click on the resource link above.
Chapter 11: Simple Regression
Available Study Resources on Quizplus for this Chatper
217 Verified Questions
217 Flashcards
Source URL: https://quizplus.com/quiz/40158
Sample Questions
Q1) The coefficient of determination can only take on positive values.
A)True
B)False
Q2) Compute the standard error of the slope of the regression line of hours on income.
A)0.256
B)0.234
C)0.211
D)0.269
Q3) Determine the value of the Student's t statistic.
A)1.34
B)0.80
C)2.67
D)3.47
Q4) What is the estimated income for a professor with 20 years of employment?
Q5) The total degrees of freedom is:
A)21
B)22
C)23
D)24
To view all questions and flashcards with answers, click on the resource link above. Page 13
Chapter 12: Multiple Regression
Available Study Resources on Quizplus for this Chatper
252 Verified Questions
252 Flashcards
Source URL: https://quizplus.com/quiz/40159
Sample Questions
Q1) Interpret the estimate b<sub>1</sub>.
Q2) What is the correct interpretation of the coefficient of determination R<sup>2</sup>?
A)The sales price equals 53% of these three variables.
B)47% of the variation in sales prices can be determined by the variation in these three variables.
C)The sales price equals 47% of these three variables.
D)The probability that the sample values will lie on the regression line is 0.47.
Q3) What do these results suggest about the relationship between the total loan amount and advertising?
A)As the amount of advertising increases,the total loan amount decreases at a decreasing rate.
B)As the amount of advertising increases,the total loan amount at first decreases,then increases.
C)As the amount of advertising increases,the total loan amount increases at an increasing rate.
D)As the amount of advertising increases,the total loan amount at first increases,then decreases.
To view all questions and flashcards with answers, click on the resource link above.
14
Chapter 13: Additional Topics in Regression Analysis
Available Study Resources on Quizplus for this Chatper
168 Verified Questions
168 Flashcards
Source URL: https://quizplus.com/quiz/40160
Sample Questions
Q1) Experimental design methods are used extensively in the study of human behavior.
A)True
B)False
Q2) Suppose you model the relationship as Y = <sub>0</sub> + <sub>1</sub>X<sub>1</sub> + <sub>2</sub>X<sub>2</sub> + <sub>3</sub>X<sub>3</sub> + <sub>5</sub>X<sub>5</sub> + <sub>6</sub>X<sub>6</sub>.What effect does being a business student have on hours studying each week?
A) <sub>5</sub> - <sub>0</sub>
B) <sub>5</sub>
C) <sub>5</sub> + <sub>0</sub>
D) <sub>5</sub> <sub>*</sub> <sub>0</sub>
Q3) Write the model specification and define the variables for a multiple regression model to predict college GPA as a function of entering SAT scores and the year in college: freshman,sophomore,junior,and senior.
Q4) In regression equations,involving several independent variables,the multicollinearity problem arises from patterns of strong intercorrelations among the independent variables.
A)True
B)False
Page 15
To view all questions and flashcards with answers, click on the resource link above.
Chapter 14: Analysis of Categorical Data
Available Study Resources on Quizplus for this Chatper
241 Verified Questions
241 Flashcards
Source URL: https://quizplus.com/quiz/40161
Sample Questions
Q1) In using the chi-square test for independence,one should be aware that the expected frequencies that are too small will lead to too big value of the probability of Type I error.
A)True
B)False
Q2) The normal approximation to the sign test is acceptable if the sample size exceeds 15.
A)True
B)False
Q3) When the number n of nonzero differences in the sample is greater than 20,which of the following distributions provide a good approximation to the distribution of the Wilcoxon signed rank statistic?
A)The chi-square distribution
B)The normal distribution
C)The F distribution
D)The Student's t distribution
Q4) To compute the p-value of a matched pairs sign test,the binomial distribution is employed.
A)True
B)False
Page 16
To view all questions and flashcards with answers, click on the resource link above.
Chapter 15: Analysis of Variance
Available Study Resources on Quizplus for this Chatper
192 Verified Questions
192 Flashcards
Source URL: https://quizplus.com/quiz/40162
Sample Questions
Q1) The number of degrees of freedom for error is:
A)29
B)15
C)8
D)4
Q2) Explain when a nonparametric test is to be used in place of the one-way ANOVA F-test,when testing the difference among several population means.
Q3) Is there sufficient evidence to reject the null hypothesis that there is no difference between different types of brochures? Use = 0.05.
Q4) The mean square error must always be positive in a two-way ANOVA experiment.
A)True
B)False
Q5) Which of the following is the calculated p-value for Blocks? (Hint: Use Excel)
A)0.52
B)0.93
C)0.20
D)0.72
Q6) Test the null hypothesis that the three population mean times are equal.Use = 0.05.
To view all questions and flashcards with answers, click on the resource link above. Page 17
Chapter 16: Time-Series Analysis and Forecasting
Available Study Resources on Quizplus for this Chatper
138 Verified Questions
138 Flashcards
Source URL: https://quizplus.com/quiz/40163
Sample Questions
Q1) What is the trend estimate for week 10?
A)38.18
B)34.40
C)43.48
D)50.00
Q2) Given a data set with 20 yearly observations,there are only twelve 9-year moving averages.
A)True
B)False
Q3) What is the seasonal index for quarter 2?
A)141.99
B)84.53
C)83.13
D)91.52
Q4) The error for the forecast that corresponds to the year 1902 is:
A)3.38
B)-14.92
C)7.71
D)10.16
Q5) Develop a seasonal index for this time series. To view all questions and flashcards with answers, click on the resource link above.
Page 18
Chapter 17: Additional Topics in Sampling
Available Study Resources on Quizplus for this Chatper
110 Verified Questions
110 Flashcards
Source URL: https://quizplus.com/quiz/40164
Sample Questions
Q1) Estimate the proportion of all students going on the field trip.
Q2) Find a 98% confidence interval for the mean monthly expenditures.
A)64.67 ± 5.285
B)64.67 ± 3.278
C)64.67 ± 7.875
D)64.67 ± 4.326
Q3) Find a 95% confidence interval for the proportion of all invoices that are from out-of-state suppliers.
A)0.313 ± 0.0739
B)0.313 ± 0.1298
C)0.313 ± 0.0426
D)0.313 ± 0.1519
Q4) Determine how many sample observations are needed under the proportional allocation scheme.
Q5) If a total sample of 120 students is taken,determine the number of juniors and seniors under the proportional allocation scheme.
Q6) Find a 95% confidence interval for the total amount of the 800 accounts receivable.
Q7) Estimate the mean monthly expenditures.
Page 19
To view all questions and flashcards with answers, click on the resource link above.