BUSINESS STATISTICS COMPREHENSIVE UPDATED
QUESTIONS AND ANSWERS SURE A+
✔✔9.89 - ✔✔Recently, students in a marketing research class were interested in the
driving behavior of students. Specifically, the marketing students were interested in
finding out if exceeding the speed limit was related to social activity. They collected the
following responses from 100 randomly selected students: What is the value of the test
statistic?
✔✔The variables are not related. - ✔✔If the correlation coefficient between two
variables, X and Y, equals zero, what can be said of the variables X and Y?
✔✔Number of contacts - ✔✔A sales manager for an advertising agency believes that
there is a relationship between the number of contacts that a salesperson makes and
the amount of sales dollars earned. What is the independent variable?
✔✔4,601 - ✔✔Given the least squares regression equation, Ŷ = 1,202 + 1,133X, when
X = 3, what does Ŷ equal?
✔✔Independent variable - ✔✔In regression analysis, what is the predictor variable
called?
✔✔It is a measure of the accuracy of the prediction. - ✔✔Which of the following is true
about the standard error of estimate?
✔✔It describes the relationship between two variables. - ✔✔Which of the following
statements regarding the coefficient of correlation is true?
✔✔0.9583 - ✔✔Using the following information: What is the correlation coefficient?
✔✔True - ✔✔A scatter diagram is a graph that portrays the correlation between a
dependent variable and an independent variable.
✔✔Strong - ✔✔If the correlation between two variables is close to one, the association
between the variables is ___________.
✔✔True - ✔✔The regression equation is used to estimate a value of the dependent
variable Y based on a selected value of the independent variable X.
✔✔A significant positive relationship exists between the variables. - ✔✔Using the
following information: The regression analysis can be summarized as follows:
✔✔0% to 100% inclusive - ✔✔What is the range of values for the coefficient of
determination?
,✔✔must be positive. - ✔✔If the correlation coefficient has a negative value, then the
coefficient of determination:
✔✔A scatter diagram - ✔✔What is the chart called when the paired data (the dependent
and independent variables) are plotted?
✔✔True - ✔✔The values of a and b in the regression equation are called the regression
coefficients.
✔✔The confidence interval is narrower than a prediction interval - ✔✔When comparing
the 95% confidence and prediction intervals for a given regression analysis
______________.
✔✔an interval or ratio scale - ✔✔The Pearson product-moment correlation coefficient, r,
requires that variables be measured with _____________.
✔✔computing the log of all values of the dependent and independent variable. - ✔✔An
example of a way to rescale a variable to create a linear relationship is:
✔✔All of them - ✔✔Which of the following are true assumptions underlying linear
regression?
(1) For each value of X, there is a group of Y values that is normally distributed.
(2) The means of these normal distributions of Y values all lie on the regression line.
(3) The standard deviations of these normal distributions are equal.
✔✔n - 2 - ✔✔What are the degrees of freedom used to test the significance of the slope
in a simple linear regression equation?
✔✔H1: β ≠ 0 - ✔✔What is the alternate hypothesis to test the significance of the slope
in a regression equation?
✔✔-12.201 - ✔✔A sales manager for an advertising agency believes that there is a
relationship between the number of contacts that a salesperson makes and the amount
of sales dollars earned. A regression analysis shows the following results: What is the
Y-intercept of the linear equation?
✔✔False - ✔✔The hypothesis to test the slope of a regression equation is H0: ? = 0.
✔✔The Y-intercept - ✔✔In the regression equation, what does the letter "a" represent?
, ✔✔-1.0 to +1.0 inclusive - ✔✔What is the range of values for a coefficient of
correlation?
✔✔False - ✔✔The strength of the correlation between two variables depends on the
sign of the coefficient of correlation.
✔✔True - ✔✔An economist is interested in predicting the unemployment rate based on
gross domestic product. Since the economist is interested in predicting unemployment,
the independent variable is gross domestic product.
✔✔0 - ✔✔If all the plots on a scatter diagram lie on a straight line, what is the standard
error of estimate?
✔✔When X = 0, Y = 10. - ✔✔Assume the least squares equation is Y = 10 + 20X. What
does the value of 10 in the equation indicate?
✔✔0.4225 - ✔✔If the correlation coefficient (r) = 0.65, what does the coefficient of
determination equal?
✔✔True - ✔✔Because the coefficient of determination is expressed as a percent, its
value is between 0% and 100%.
✔✔94% of the total variation of the dependent variable is explained by the independent
variable. - ✔✔If the coefficient of determination is 0.94, what can we say about the
relationship between two variables?
✔✔It is not zero. - ✔✔If we reject the null hypothesis, what can we conclude about the
population correlation coefficient?
✔✔Independent variable - ✔✔What is the variable used to predict another variable
called?
✔✔0.176 - ✔✔A sales manager for an advertising agency believes that there is a
relationship between the number of contacts that a salesperson makes and the amount
of sales dollars earned. A regression analysis shows the following results: What is the
standard error of the slope?
✔✔True - ✔✔A confidence interval can be determined for the mean value of Y for a
given value of X.
✔✔They both use the standard error of estimate. - ✔✔Which of the following are the
same between a confidence interval and a prediction interval?
QUESTIONS AND ANSWERS SURE A+
✔✔9.89 - ✔✔Recently, students in a marketing research class were interested in the
driving behavior of students. Specifically, the marketing students were interested in
finding out if exceeding the speed limit was related to social activity. They collected the
following responses from 100 randomly selected students: What is the value of the test
statistic?
✔✔The variables are not related. - ✔✔If the correlation coefficient between two
variables, X and Y, equals zero, what can be said of the variables X and Y?
✔✔Number of contacts - ✔✔A sales manager for an advertising agency believes that
there is a relationship between the number of contacts that a salesperson makes and
the amount of sales dollars earned. What is the independent variable?
✔✔4,601 - ✔✔Given the least squares regression equation, Ŷ = 1,202 + 1,133X, when
X = 3, what does Ŷ equal?
✔✔Independent variable - ✔✔In regression analysis, what is the predictor variable
called?
✔✔It is a measure of the accuracy of the prediction. - ✔✔Which of the following is true
about the standard error of estimate?
✔✔It describes the relationship between two variables. - ✔✔Which of the following
statements regarding the coefficient of correlation is true?
✔✔0.9583 - ✔✔Using the following information: What is the correlation coefficient?
✔✔True - ✔✔A scatter diagram is a graph that portrays the correlation between a
dependent variable and an independent variable.
✔✔Strong - ✔✔If the correlation between two variables is close to one, the association
between the variables is ___________.
✔✔True - ✔✔The regression equation is used to estimate a value of the dependent
variable Y based on a selected value of the independent variable X.
✔✔A significant positive relationship exists between the variables. - ✔✔Using the
following information: The regression analysis can be summarized as follows:
✔✔0% to 100% inclusive - ✔✔What is the range of values for the coefficient of
determination?
,✔✔must be positive. - ✔✔If the correlation coefficient has a negative value, then the
coefficient of determination:
✔✔A scatter diagram - ✔✔What is the chart called when the paired data (the dependent
and independent variables) are plotted?
✔✔True - ✔✔The values of a and b in the regression equation are called the regression
coefficients.
✔✔The confidence interval is narrower than a prediction interval - ✔✔When comparing
the 95% confidence and prediction intervals for a given regression analysis
______________.
✔✔an interval or ratio scale - ✔✔The Pearson product-moment correlation coefficient, r,
requires that variables be measured with _____________.
✔✔computing the log of all values of the dependent and independent variable. - ✔✔An
example of a way to rescale a variable to create a linear relationship is:
✔✔All of them - ✔✔Which of the following are true assumptions underlying linear
regression?
(1) For each value of X, there is a group of Y values that is normally distributed.
(2) The means of these normal distributions of Y values all lie on the regression line.
(3) The standard deviations of these normal distributions are equal.
✔✔n - 2 - ✔✔What are the degrees of freedom used to test the significance of the slope
in a simple linear regression equation?
✔✔H1: β ≠ 0 - ✔✔What is the alternate hypothesis to test the significance of the slope
in a regression equation?
✔✔-12.201 - ✔✔A sales manager for an advertising agency believes that there is a
relationship between the number of contacts that a salesperson makes and the amount
of sales dollars earned. A regression analysis shows the following results: What is the
Y-intercept of the linear equation?
✔✔False - ✔✔The hypothesis to test the slope of a regression equation is H0: ? = 0.
✔✔The Y-intercept - ✔✔In the regression equation, what does the letter "a" represent?
, ✔✔-1.0 to +1.0 inclusive - ✔✔What is the range of values for a coefficient of
correlation?
✔✔False - ✔✔The strength of the correlation between two variables depends on the
sign of the coefficient of correlation.
✔✔True - ✔✔An economist is interested in predicting the unemployment rate based on
gross domestic product. Since the economist is interested in predicting unemployment,
the independent variable is gross domestic product.
✔✔0 - ✔✔If all the plots on a scatter diagram lie on a straight line, what is the standard
error of estimate?
✔✔When X = 0, Y = 10. - ✔✔Assume the least squares equation is Y = 10 + 20X. What
does the value of 10 in the equation indicate?
✔✔0.4225 - ✔✔If the correlation coefficient (r) = 0.65, what does the coefficient of
determination equal?
✔✔True - ✔✔Because the coefficient of determination is expressed as a percent, its
value is between 0% and 100%.
✔✔94% of the total variation of the dependent variable is explained by the independent
variable. - ✔✔If the coefficient of determination is 0.94, what can we say about the
relationship between two variables?
✔✔It is not zero. - ✔✔If we reject the null hypothesis, what can we conclude about the
population correlation coefficient?
✔✔Independent variable - ✔✔What is the variable used to predict another variable
called?
✔✔0.176 - ✔✔A sales manager for an advertising agency believes that there is a
relationship between the number of contacts that a salesperson makes and the amount
of sales dollars earned. A regression analysis shows the following results: What is the
standard error of the slope?
✔✔True - ✔✔A confidence interval can be determined for the mean value of Y for a
given value of X.
✔✔They both use the standard error of estimate. - ✔✔Which of the following are the
same between a confidence interval and a prediction interval?
