Econ 261 - Test 3

The range of the Durbin-Watson statistic is from a. 0 to 4. b. -∞ to +∞. c. 0 to 1. d. -1 to 1.

a. 0 to 4.

In regression analysis, the error term ε is a random variable with a mean or expected value of a. 0. b. 1. c. μ. d. x

a. 0.

Which of the following tests is used to determine whether an additional variable makes a significant contribution to a multiple regression model? a. an F test b. a z test c. a t test d. a chi-square test

a. an F test

The correlation in error terms that arises when the error terms at successive points in time are related is termed a. autocorrelation. b. interaction. c. leverage. d. multicorrelation.

a. autocorrelation.

A least squares regression line a. can be used to predict a value of y if the corresponding x value is given. b. ensures that the predictions of y outside the range of the values of x are valid. c. can only be determined if a good linear relationship exists between x and y. d. implies a cause-and-effect relationship between x and y.

a. can be used to predict a value of y if the corresponding x value is given.

The coefficient of determination a. Answer cannot be negative. b. is the square root of the coefficient of correlation. c. is the same as the coefficient of correlation. d. can be negative or positive.

a. cannot be negative.

In factorial designs, the response produced when the treatments of one factor interact with the treatments of another in influencing the response variable is known as a. interaction. b. error. c. main effect. d. replication.

a. interaction.

A population where each of its element is assigned to one and only one of several classes or categories is a _____ population. a. multinomial b. Poisson c. normal d. binomial

a. multinomial

A measure of goodness of fit for the estimated regression equation is the a. multiple coefficient of determination. b. multicollinearity. c. mean square due to regression. d. studentized residual.

a. multiple coefficient of determination.

If there are three or more populations, then it is a. possible to test for equality of three or more population proportions. b. impossible to test for equality of the three population proportions, because chi-square tests deal with only two populations. c. customary to use a t distribution to test for equality of the three population proportions. d. reasonable to test for equality of multiple population proportions using chi-square lower tail tests.

a. possible to test for equality of three or more population proportions.

Marascuilo procedure is used to test for a significant difference between pairs of population a. proportions. b. means. c. variances. d. standard deviations.

a. proportions.

The time series component that exhibits a repeating pattern over successive periods, often one-year intervals is called a(n) _____ component. a. seasonal b. irregular c. cyclical d. trend

a. seasonal

The objective of smoothing methods is to smooth out​ a. ​random fluctuations. ​b. long range forecasts. ​c. wide seasonal variations. ​d. significant trend effects.

a. ​random fluctuations.

When dealing with the problem of nonconstant variance, the reciprocal transformation means using a. y2 as the dependent variable instead of y. b. 1/y as the dependent variable instead of y. c. 1/x as the independent variable instead of x. d. x2 as the independent variable instead of x.

b. 1/y as the dependent variable instead of y.

The degrees of freedom for a data table with 10 rows and 10 columns is a. 100. b. 81. c. 18. d. 20.

b. 81. (R-1)*(C-1) R = 10 C = 10

A measure of identifying the effect of an unusual x value on the regression results is called a. Cook's D. b. Leverage. c. odd ratio. d. unusual regression.

b. Leverage.

If there is a very strong correlation between two variables, then the coefficient of determination must be a. much smaller than -1, if the correlation is negative. b. closer or equal to 1. c. much larger than 1, if the correlation is positive. d. equal to zero.

b. closer or equal to 1.

In regression analysis, the response variable is the a. independent variable. b. dependent variable. c. slope of the regression function. d. intercept.

b. dependent variable.

In the ANOVA, treatments refer to a. experimental units. b. different levels of a factor. c. the dependent variables. d. statistical applications.

b. different levels of a factor.

In a regression analysis, the standard error of the estimate is determined to be 4. In this situation, the MSE a. is 2. b. is 16. c. depends on the sample size. d. requires a known SSE.

b. is 16.

The mean square is the sum of squares divided by a. the total number of observations. b. its corresponding degrees of freedom. c. its corresponding degrees of freedom minus one. d. the total number of replications.

b. its corresponding degrees of freedom.

Models in which the parameters have exponents other than 1 are called a. linear models. b. nonlinear models. c. autocorrelated models. d. independent models.

b. nonlinear models.

The trend component is easy to identify using the method of a. moving averages. b. regression analysis. c. naïve forecasting. d. exponential smoothing.

b. regression analysis.

The number of times each experimental condition is observed in a factorial design is known as a. partition. b. replication. c. blocking. d. factor.

b. replication.

In the analysis of variance procedure (ANOVA), "factor" refers to a. the dependent variable. b. the independent variable. c. different levels of a treatment. d. the critical value of F.

b. the independent variable.

The equation that describes how the dependent variable (y) is related to the independent variable (x) is called a. the correlation model. b. the regression model. c. correlation analysis. d. estimation analysis.

b. the regression model.

Serial correlation is a. used to identify the effects of multicollinearity. b. the same as autocorrelation. c. the same as leverage. d. the correlation between serial numbers of the independent variables.

b. the same as autocorrelation.

Correlation analysis is used to determine a. the equation of the regression line. b. the strength of the linear relationship between the dependent and the independent variables. c. a specific value of the dependent variable for a given value of the independent variable. d. a cause-and-effect relationship between the dependent and the independent variables.

b. the strength of the linear relationship between the dependent and the independent variables.

The time series component that reflects gradual variability over a long time period is called a(n) _____ component. a. cyclical b. trend c. irregular d. seasonal

b. trend

The time series component which reflects gradual shifts or movements to relatively higher or lower values over a longer period of time is a(n) _____ component. a. cyclical b. trend c. irregular d. seasonal

b. trend

Gradual shifting or movement of a time series to relatively higher or lower values over a longer period of time is called​ a. seasonality. b. ​trend. ​c. indexing. d. a ​cycle.

b. ​trend.

The multiple coefficient of determination is a. MSR/MST. b. MSR/MSE. c. SSR/SST. d. SSE/SSR.

c. SSR/SST.

A variable that takes on the values of 0 or 1 and is used to incorporate the effect of categorical independent variables in a regression model is called a. an interaction. b. a constant variable. c. a dummy variable. d. a logit variable.

c. a dummy variable.

If the coefficient of determination is a positive value, then the coefficient of correlation a. must also be positive. b. must be zero. c. can be either positive or negative. d. can be larger than 1.

c. can be either positive or negative.

The proportion of the variation in the dependent variable y that is explained by the estimated regression equation is measured by the​ a. correlation coefficient. ​b. standard error of the estimate. c. coefficient of determination. ​d. confidence interval estimate.

c. coefficient of determination.

An experimental design where the experimental units are randomly assigned to the treatments is known as _____ design. a. factor block b. random factor c. completely randomized d. randomized treatment

c. completely randomized

A component of the time series model that results in the multi-period above-trend and below-trend behavior of a time series is a(n) _____ component. a. trend b. seasonal c. cyclical d. irregular

c. cyclical

The model developed from sample data that has the form of = b0 + b1x is known as the a. regression equation. b. correlation model. c. estimated regression equation. d. regression model.

c. estimated regression equation.

A statistical test conducted to determine whether to reject or not reject a hypothesized probability distribution for a population is known as a _____ test. a. comparison b. probability c. goodness of fit d. normality

c. goodness of fit

The time series pattern that exists when the data fluctuate around a constant mean is the _____ pattern. a. cyclical b. seasonal c. horizontal d. trend

c. horizontal

The component that reflects unexplained variability in the time series is called a(n) _____ component. a. cyclical b. seasonal c. irregular d. trend

c. irregular

In a situation where the dependent variable can assume only one of the two possible discrete values, a. we must use multiple regression. b. there can only be two independent variables. c. logistic regression should be applied. d. all the independent variables must have values of either zero or one.

c. logistic regression should be applied.

A term used to describe the case when the independent variables in a multiple regression model are correlated is a. regression. b. correlation. c. multicollinearity. d. leverage.

c. multicollinearity.

Regression analysis is a statistical procedure for developing a mathematical equation that describes how a. several independent and several dependent variables are related. b. one dependent, one independent, and several error variables are related. c. one dependent and one or more independent variables are related. d. one independent and one or more dependent variables are related.

c. one dependent and one or more independent variables are related.

The number of degrees of freedom associated with the chi-square distribution in a test of independence is number of _____ minus 1. a. sample items b. populations c. rows minus 1 times number of columns d. populations minus number of estimated parameters

c. rows minus 1 times number of columns

If data for a time series analysis are collected on an annual basis only, which of the following components may be ignored? a. irregular b. trend c. seasonal d. cyclical

c. seasonal

The following regression model ​ y = β0 + β1x1 + β2 + ε ​is known as a a. simple first-order model with one predictor variable. b. simple first-order model with two predictor variables. c. second-order model with one predictor variable. d. second-order model with two predictor variables.

c. second-order model with one predictor variable.

A parameter of the exponential smoothing model that provides the weight given to the most recent time series value in the calculation of the forecast value is known as the a. exponential estimate. b. mean absolute error. c. smoothing constant. d. mean squared error.

c. smoothing constant.

In logistic regression, a. there can only be two independent variables. b. there are two dependent variables. c. the dependent variable only assumes two discrete values. d. the dependent variable only assumes two continuous values.

c. the dependent variable only assumes two discrete values.

In a multiple regression model, the variance of the error term ε is assumed to be a. the same for all values of the dependent variable. b. zero. c. the same for all values of the independent variable. d. one.

c. the same for all values of the independent variable.

In simple linear regression, r2 is the a. mean square error. ​b. correlation coefficient. c. squared residual. d. coefficient of determination.

coefficient of determination.

The degrees of freedom for a table with 7 rows and 4 columns is a. 28. b. 11. c. 9. d. 18.

d. 18. (R-1)*(C-1) R = 7 C = 4

When individuals in a sample of 150 were asked whether or not they supported capital punishment, the following information was obtained. Do you supportcapital punishment? Number of individuals Yes 45 No 55 No Opinion 50 We are interested in determining whether or not the opinions of the individuals (as to Yes, No, and No Opinion) are uniformly distributed. The expected frequency for each group is a. .333. .b. 50. c. 1/3. d. 50.

d. 50.

An important application of the chi-square distribution is a. making inferences about a single population variance. b. testing for goodness of fit. c. testing for the independence of two categorical variables. d. All of these alternatives are correct.

d. All of these alternatives are correct.

A test used to determine whether or not first-order autocorrelation is present is _____ test. a. t b. chi-square c. serial-autocorrelation d. Durbin-Watson

d. Durbin-Watson

When an analysis of variance is performed on samples drawn from k populations, the mean square due to treatments (MSTR) is a. SSTR/nT. b. SSTR/(nT - 1). c. SSTR/k. d. SSTR/(k - 1).

d. SSTR/(k - 1).

A variable such as z, whose value is z = x1x2, is added to a general linear model in order to account for potential effects of two variables x1 and x2 acting together. This type of effect is a. impossible to occur. b. called multicollinearity effect. c. one of the transformation effects. d. called interaction.

d. called interaction.

All the independent variables in a multiple regression analysis a. must be quantitative. b. must assume only positive values. c. must be either quantitative or qualitative but not a mix of both. d. can be either quantitative or qualitative or both.

d. can be either quantitative or qualitative or both.

In multiple regression analysis, a variable that cannot be measured in numerical terms is called a a. nonmeasurable random variable. b. constant variable. c. dependent variable. d. categorical independent variable.

d. categorical independent variable.

The sampling distribution for a goodness of fit test is the _____ distribution. a. Poisson b. t c. normal d. chi-square

d. chi-square

The interval estimate of the mean value of y for a given value of x is the a. prediction interval estimate. b. average regression interval. c. x versus y correlation interval. d. confidence interval estimate

d. confidence interval estimate

Which of the following is not present in a time series? a. seasonality b. cyclical pattern c. trend d. cross-sectional pattern

d. cross-sectional pattern

A method that uses a weighted average of past values for arriving at smoothed time series values is known as a. a moving average. b. additive approach. c. a smoothing average. d. exponential smoothing.

d. exponential smoothing.

The independent variable of interest in an ANOVA procedure is called a a. partition. b. treatment. c. response. d. factor.

d. factor.

The process of allocating the total sum of squares and degrees of freedom to the various components is called a. factoring. b. blocking. c. replicating. d. partitioning.

d. partitioning.

If the coefficient of correlation is a negative value, then the a. intercept of the regression line must also be positive. b. coefficient of determination can be either a negative or a positive value, depending on the slope. c. regression equation could have either a positive or a negative slope. d. slope of the regression line must be negative.

d. slope of the regression line must be negative.

The standard error of the estimate is the a. standard deviation of t. b. square root of SSE. c. square root of SST. d. square root of MSE.

d. square root of MSE.

The ANOVA procedure is a statistical approach for determining whether or not the means of _____ are equal. a. two samples b. two or more samples c. two populations d. three or more populations

d. three or more populations