Exam (elaborations) TEST BANK INTRODUCTORY ECONOMETRICS A Modern Approach, 5th Edition by Jeffrey M. Wooldridge

Exam (elaborations) TEST BANK INTRODUCTORY ECONOMETRICS A Modern Approach, 5th Edition by Jeffrey M. Wooldridge Test Bank –Introductory Econometrics: A Modern Approach, 5th Edition by Jeffrey M. Wooldridge With PERFECT SOLUTION AVAILABLE OF ALL CHAPTERS Chapter 1 1. Econometrics is the branch of economics that _____. a. studies the behavior of individual economic agents in making economic decisions b. develops and uses statistical methods for estimating economic relationships c. deals with the performance, structure, behavior, and decision-making of an economy as a whole d. applies mathematical methods to represent economic theories and solve economic problems. Answer: b Difficulty: Easy Bloom’s: Knowledge A-Head: What is Econometrics? BUSPROG: Feedback: Econometrics is the branch of economics that develops and uses statistical methods for estimating economic relationships. 2. Nonexperimental data is called _____. a. cross-sectional data b. time series data c. observational data d. panel data Answer: c Difficulty: Easy Bloom’s: Knowledge A-Head: What is Econometrics? BUSPROG: Feedback: 3. Which of the following is true of experimental data? a. Experimental data are collected in laboratory environments in the natural sciences. b. Experimental data cannot be collected in a controlled environment. c. Experimental data is sometimes called observational data. d. Experimental data is sometimes called retrospective data. Answer: a Difficulty: Easy Bloom’s: Knowledge A-Head: What is Econometrics? BUSPROG: Feedback: 4. An empirical analysis relies on _____to test a theory. a. common sense Downloaded by Ndlovu Lizuzu () lOMoARcPSD| b. ethical considerations c. data d. customs and conventions Answer: c Difficulty: Easy Bloom’s: Knowledge A-Head: Steps in Empirical Economic Analysis BUSPROG: Feedback: An empirical analysis relies on data to test a theory. 5. The term ‘u’ in an econometric model is usually referred to as the _____. a. error term b. parameter c. hypothesis d. dependent variable Answer: a Difficulty: Easy Bloom’s: Knowledge A-Head: Steps in Empirical Economic Analysis BUSPROG: Feedback: The term u in an econometric model is called the error term or disturbance term. 6. The parameters of an econometric model _____. a. include all unobserved factors affecting the variable being studied b. describe the strength of the relationship between the variable under study and the factors affecting it c. refer to the explanatory variables included in the model d. refer to the predictions that can be made using the model Answer: b Difficulty: Easy Bloom’s: Knowledge A-Head: Steps in Empirical Economic Analysis BUSPROG: Feedback: The parameters of an econometric model describe the direction and strength of the relationship between the variable under study and the factors affecting it. 7. Which of the following is the first step in empirical economic analysis? a. Collection of data b. Statement of hypotheses c. Specification of an econometric model d. Testing of hypotheses Answer: c Difficulty: Easy Bloom’s: Knowledge A-Head: Steps in Empirical Economic Analysis Downloaded by Ndlovu Lizuzu () lOMoARcPSD| BUSPROG: Feedback: The first step in empirical economic analysis is the specification of the econometric model. 8. A data set that consists of a sample of individuals, households, firms, cities, states, countries, or a variety of other units, taken at a given point in time, is called a(n) _____. a. cross-sectional data set b. longitudinal data set c. time series data set d. experimental data set Answer: a Difficulty: Easy Bloom’s: Knowledge A-Head: The Structure of Economic Data BUSPROG: Feedback: A data set that consists of a sample of individuals, households, firms, cities, states, countries, or a variety of other units, taken at a given point in time, is called a cross-sectional data set. 9. Data on the income of law graduates collected at different times during the same year is_____. a. panel data b. experimental data c. time series data d. cross-sectional data Answer: d Difficulty: Easy Bloom’s: Application A-Head: The Structure of Economic Data BUSPROG: Analytic Feedback: A data set that consists of a sample of individuals, households, firms, cities, states, countries, or a variety of other units, taken at a given point in time, is called a cross-sectional data set. Therefore, data on the income of law graduates on a particular year are examples of cross-sectional data. 10. A data set that consists of observations on a variable or several variables over time is called a _____ data set. a. binary b. cross-sectional c. time series d. experimental Answer: c Difficulty: Easy Bloom’s: Knowledge A-Head: The Structure of Economic Data BUSPROG: Feedback: A time-series data set consists of observations on a variable or several variables over time. 11. Which of the following is an example of time series data? Downloaded by Ndlovu Lizuzu () lOMoARcPSD| a. Data on the unemployment rates in different parts of a country during a year. b. Data on the consumption of wheat by 200 households during a year. c. Data on the gross domestic product of a country over a period of 10 years. d. Data on the number of vacancies in various departments of an organization on a particular month. Answer: c Difficulty: Easy Bloom’s: Application A-Head: The Structure of Economic Data BUSPROG: Analytic Feedback: A time-series data set consists of observations on a variable or several variables over time. Therefore, data on the gross domestic product of a country over a period of 10 years is an example of time series data. 12. Which of the following refers to panel data? a. Data on the unemployment rate in a country over a 5-year period b. Data on the birth rate, death rate and population growth rate in developing countries over a 10-year period. c. Data on the income of 5 members of a family on a particular year. d. Data on the price of a company’s share during a year. Answer: b Difficulty: Easy Bloom’s: Application A-Head: The Structure of Economic Data BUSPROG: Analytic Feedback: A panel data set consists of a time series for each cross-sectional member in the data set. Therefore, data on the birth rate, death rate and infant mortality rate in developing countries over a 10- year period refers to panel data. 13. Which of the following is a difference between panel and pooled cross-sectional data? a. A panel data set consists of data on different cross-sectional units over a given period of time while a pooled data set consists of data on the same cross-sectional units over a given period of time. b. A panel data set consists of data on the same cross-sectional units over a given period of time while a pooled data set consists of data on different cross-sectional units over a given period of time c. A panel data consists of data on a single variable measured at a given point in time while a pooled data set consists of data on the same cross-sectional units over a given period of time. d. A panel data set consists of data on a single variable measured at a given point in time while a pooled data set consists of data on more than one variable at a given point in time. Answer: b Difficulty: Easy Bloom’s: Knowledge A-Head: The Structure of Economic Data BUSPROG: Feedback: A panel data set consists of data on the same cross-sectional units over a given period of time Downloaded by Ndlovu Lizuzu () lOMoARcPSD| while a pooled data set consists of data on the same cross-sectional units over a given period of time. 14. _____ has a causal effect on _____. a. Income; unemployment b. Height; health c. Income; consumption d. Age; wage Answer: c Difficulty: Moderate Bloom’s: Application A-Head: Causality and the Notion of Ceteris Paribus in Econometric Analysis BUSPROG: Analytic Feedback: Income has a causal effect on consumption because an increase in income leads to an increase in consumption. 15. Which of the following is true? a. A variable has a causal effect on another variable if both variables increase or decrease simultaneously. b. The notion of ‘ceteris paribus’ plays an important role in causal analysis. c. Difficulty in inferring causality disappears when studying data at fairly high levels of aggregation. d. The problem of inferring causality arises if experimental data is used for analysis. Answer: b Difficulty: Moderate Bloom’s: Knowledge A-Head: Causality and the Notion of Ceteris Paribus in Econometric Analysis BUSPROG: Feedback: The notion of ‘ceteris paribus’ plays an important role in causal analysis. 16. Experimental data are sometimes called retrospective data. Answer: False Difficulty: Easy Bloom’s: Knowledge A-Head: What is Econometrics? BUSPROG: Feedback: Nonexperimental data are sometimes called retrospective data. 17. An economic model consists of mathematical equations that describe various relationships between economic variables. Answer: True Difficulty: Easy Bloom’s: Knowledge A-Head: Steps in Empirical Economic Analysis Downloaded by Ndlovu Lizuzu () lOMoARcPSD| BUSPROG: Feedback: An economic model consists of mathematical equations that describe various relationships between economic variables. 18. A cross-sectional data set consists of observations on a variable or several variables over time. Answer: False Difficulty: Easy Bloom’s: Knowledge A-Head: The Structure of Economic Data BUSPROG: Feedback: A time series data set consists of observations on a variable or several variables over time. 19. A time series data is also called a longitudinal data set. Answer: False Difficulty: Easy Bloom’s: Knowledge A-Head: The Structure of Economic Data BUSPROG: Feedback: A time series data is also called a longitudinal data set. 20. The notion of ceteris paribus means “other factors being equal.” Answer: True Difficulty: Easy Bloom’s: Knowledge A-Head: Causality and the Notion of Ceteris Paribus in Econometric Analysis BUSPROG: Feedback: The notion of ceteris paribus means “other factors being equal.” Chapter 2 1. A dependent variable is also known as a(n) _____. a. explanatory variable b. control variable c. predictor variable d. response variable Answer: d Difficulty: Easy Bloom’s: Knowledge A-Head: Definition of the Simple Regression Model BUSPROG: Feedback: A dependent variable is known as a response variable. Downloaded by Ndlovu Lizuzu () lOMoARcPSD| 2. If a change in variable x causes a change in variable y, variable x is called the _____. a. dependent variable b. explained variable c. explanatory variable d. response variable Answer: c Difficulty: Easy Bloom’s: Comprehension A-Head: Definition of the Simple Regression Model BUSPROG: Feedback: If a change in variable x causes a change in variable y, variable x is called the independent variable or the explanatory variable. 3. In the equation y = β0 + β1 x + u, β0 is the _____. a. dependent variable b. independent variable c. slope parameter d. intercept parameter Answer: d Difficulty: Easy Bloom’s: Knowledge A-Head: Definition of the Simple Regression Model BUSPROG: Feedback: In the equation y = β0 + β1 x + u, β0 is the intercept parameter. 4. In the equation y = β0 + β1 x + u, what is the estimated value of β0 ? a. y−^β1 x b. y+β1 x c. y yi−¿ ¿¿ (xi−x)¿ Σi =1 n ¿ ¿ d. Σ i=1 n xy Answer: a Difficulty: Easy Bloom’s: Knowledge A-Head: Deriving the Ordinary Least Squares Estimates BUSPROG: Downloaded by Ndlovu Lizuzu () lOMoARcPSD| Feedback: The estimated value of β0 is y−^β1 x . 5. In the equation c = β0 + β1 i + u, c denotes consumption and i denotes income. What is the residual for the 5th observation if c5 =$500 and ^c5 =$475? a. $975 b. $300 c. $25 d. $50 Answer: c Difficulty: Easy Bloom’s: Knowledge A-Head: Deriving the Ordinary Least Squares Estimates BUSPROG: Feedback: The formula for calculating the residual for the ith observation is ^ui=yi−^yi . In this case, the residual is ^u5=c5−^c5 =$500 -$475= $25. 6. What does the equation ^y=^β0+^β1 x denote if the regression equation is y = β0 + β1x1 + u? a. The explained sum of squares b. The total sum of squares c. The sample regression function d. The population regression function Answer: c Difficulty: Easy Bloom’s: Knowledge A-Head: Deriving the Ordinary Least Squares Estimates BUSPROG: Feedback: The equation ^y=^β0+^β 1 x denotes the sample regression function of the given regression model. 7. Consider the following regression model: y = β0 + β1x1 + u. Which of the following is a property of Ordinary Least Square (OLS) estimates of this model and their associated statistics? a. The sum, and therefore the sample average of the OLS residuals, is positive. b. The sum of the OLS residuals is negative. c. The sample covariance between the regressors and the OLS residuals is positive. d. The point ( x , y ) always lies on the OLS regression line. Answer: d Difficulty: Easy Bloom’s: Knowledge A-Head: Properties of OLS on Any Sample of Data BUSPROG: Feedback: An important property of the OLS estimates is that the point ( x , y ) always lies on the OLS regression line. In other words, if x=x , the predicted value of y is y . Downloaded by Ndlovu Lizuzu () lOMoARcPSD| 8. The explained sum of squares for the regression function, yi=β0+β1 x1+u1 , is defined as _____. a. Σ i=1 n ( yi−y )2 b. Σ i=1 n ( yi−^y )2 c. Σ i =1 n ^ui d. Σ i=1 n (ui)2 Answer: b Difficulty: Easy Bloom’s: Knowledge A-Head: Properties of OLS on Any Sample of Data BUSPROG: Feedback: The explained sum of squares is defined as Σ i=1 n ( yi−^y )2 9. If the total sum of squares (SST) in a regression equation is 81, and the residual sum of squares (SSR) is 25, what is the explained sum of squares (SSE)? a. 64 b. 56 c. 32 d. 18 Answer: b Difficulty: Moderate Bloom’s: Application A-Head: Properties of OLS on Any Sample of Data BUSPROG: Analytic Feedback: Total sum of squares (SST) is given by the sum of explained sum of squares (SSE) and residual sum of squares (SSR). Therefore, in this case, SSE=81-25=56. 10. If the residual sum of squares (SSR) in a regression analysis is 66 and the total sum of squares (SST) is equal to 90, what is the value of the coefficient of determination? a. 0.73 b. 0.55 c. 0.27 d. 1.2 Answer: c Difficulty: Moderate Bloom’s: Application A-Head: Properties of OLS on Any Sample of Data BUSPROG: Analytic Downloaded by Ndlovu Lizuzu () lOMoARcPSD| Feedback: The formula for calculating the coefficient of determination is R2=1−SSR SST . In this case, R2=1− 66 90 =0.27 11. Which of the following is a nonlinear regression model? a. y = β0 + β1x1/2 + u b. log y = β0 + β1log x +u c. y = 1 / (β0 + β1x) + u d. y = β0 + β1x + u Answer: c Difficulty: Moderate Bloom’s: Comprehension A-Head: Properties of OLS on Any Sample of Data BUSPROG: Feedback: A regression model is nonlinear if the equation is nonlinear in the parameters. In this case, y=1 / (β0 + β1x) + u is nonlinear as it is nonlinear in its parameters. 12. Which of the following is assumed for establishing the unbiasedness of Ordinary Least Square (OLS) estimates? a. The error term has an expected value of 1 given any value of the explanatory variable. b. The regression equation is linear in the explained and explanatory variables. c. The sample outcomes on the explanatory variable are all the same value. d. The error term has the same variance given any value of the explanatory variable. Answer: d Difficulty: Easy Bloom’s: Knowledge A-Head: Expected Values and Variances of the OLS Estimators BUSPROG: Feedback: The error u has the same variance given any value of the explanatory variable. 13. The error term in a regression equation is said to exhibit homoskedasticty if _____. a. it has zero conditional mean b. it has the same variance for all values of the explanatory variable. c. it has the same value for all values of the explanatory variable d. if the error term has a value of one given any value of the explanatory variable. Answer: b Difficulty: Easy Bloom’s: Knowledge A-Head: Expected Values and Variances of the OLS Estimators BUSPROG: Feedback: The error term in a regression equation is said to exhibit homoskedasticty if it has the same Downloaded by Ndlovu Lizuzu () lOMoARcPSD| variance for all values of the explanatory variable. 14. In the regression of y on x, the error term exhibits heteroskedasticity if _____. a. it has a constant variance b. Var(y|x) is a function of x c. x is a function of y d. y is a function of x Answer: b Difficulty: Easy Bloom’s: Knowledge A-Head: Expected Values and Variances of the OLS Estimators BUSPROG: Feedback: Heteroskedasticity is present whenever Var(y|x) is a function of x because Var(u|x) = Var(y|x). 15. What is the estimated value of the slope parameter when the regression equation, y = β0 + β1x1 + u passes through the origin? a. Σ i=1 n yi b. y¿¿¿ Σi =1 n ¿ ) c. Σ i=1 n xi yi d. Σ i =1 n ( yi−y )2 Answer: c Difficulty: Easy Bloom’s: Knowledge A-Head: Regression through the Origin and Regression on a Constant BUSPROG: Feedback: The estimated value of the slope parameter when the regression equation passes through the origin is Σ i =1 n xi yi . 16. A natural measure of the association between two random variables is the correlation coefficient. Answer: True Difficulty: Easy Bloom’s: Knowledge A-Head: Definition of the Simple Regression Model Downloaded by Ndlovu Lizuzu () lOMoARcPSD| BUSPROG: Feedback: A natural measure of the association between two random variables is the correlation coefficient. 17. The sample covariance between the repressors and the Ordinary Least Square (OLS) residuals is always positive. Answer: False Difficulty: Easy Bloom’s: Knowledge A-Head: Properties of OLS on Any Sample of Data BUSPROG: Feedback: The sample covariance between the regressors and the Ordinary Least Square (OLS) residuals is zero. 18. R2 is the ratio of the explained variation compared to the total variation. Answer: True Difficulty: Easy Bloom’s: Knowledge A-Head: Properties of OLS on Any Sample of Data BUSPROG: Feedback: The sample covariance between the regressors and the Ordinary Least Square (OLS) residuals is zero. 19. There are n-1 degrees of freedom in Ordinary Least Square residuals. Answer: False Difficulty: Easy Bloom’s: Knowledge A-Head: Expected Values and Variances of the OLS Estimators BUSPROG: Feedback: There are n-2 degrees of freedom in Ordinary Least Square residuals. 20. The variance of the slope estimator increases as the error variance decreases. Answer: False Difficulty: Easy Bloom’s: Knowledge A-Head: Expected Values and Variances of the OLS Estimators BUSPROG: Feedback: The variance of the slope estimator increases as the error variance increases. Chapter 3 Downloaded by Ndlovu Lizuzu () lOMoARcPSD| 1. In the equation, y=β0+β1 x1+β2 x2+u , β2 is a(n) _____. a. independent variable b. dependent variable c. slope parameter d. intercept parameter Answer: c Difficulty: Easy Bloom’s: Knowledge A-Head: Motivation for Multiple Regression BUSPROG: Feedback: In the equation, y=β0+β1 x1+β2 x2+u , β2 is a slope parameter. 2. Consider the following regression equation: y=β1+β2 x1+ β2 x2+u . What does β1 imply? a. β1 measures the ceteris paribus effect of x1 on x2 . b. β1 measures the ceteris paribus effect of y on x1 . c. β1 measures the ceteris paribus effect of x1 on y . d. β1 measures the ceteris paribus effect of x1 on u . Answer: c Difficulty: Easy Bloom’s: Knowledge A-Head: Motivation for Multiple Regression BUSPROG: Feedback: β1 measures the ceteris paribus effect of x1 on y . 3. If the explained sum of squares is 35 and the total sum of squares is 49, what is the residual sum of squares? a. 10 b. 12 c. 18 d. 14 Answer: d Difficulty: Easy Bloom’s: Knowledge A-Head: Mechanics and Interpretation of Ordinary Least Squares BUSPROG: Analytic Feedback: The residual sum of squares is obtained by subtracting the explained sum of squares from the total sum of squares, or 49-35=14. 4. Which of the following is true of R2? a. R2 is also called the standard error of regression. b. A low R2 indicates that the Ordinary Least Squares line fits the data well. c. R2 usually decreases with an increase in the number of independent variables in a regression. d. R2 shows what percentage of