QMB3200 Exam 3
Regression analysis was applied between sales (in $1000) and advertising (in $100) and the following regression function was obtained. y-hat = 500 + 4x Based on the above estimated regression line if advertising is $10,000, then the point estimate for sales (in dollars) is
$900,000
A regression analysis involved 6 independent variables and 27 observations. The critical value of t for testing the significance of each of the independent variable's coefficients will have
20 degrees of freedom
In an analysis of variance problem if SST = 120 and SSTR = 80, then SSE is
40
A variable that takes on the values of 0 or 1 and is used to incorporate the effect of qualitative variables in a regression model is called
a dummy variable
A regression model in which more than one independent variable is used to predict the dependent variable is called
a multiple regression model
A variable that cannot be measured in numerical terms is called
a qualitative variable
If an independent variable is added to a multiple regression model, the R^2 value
becomes larger even if the variable added is not statistically significant
If the coefficient of determination is a positive value, then the regression equation
could have either a positive or a negative slope
A regression analysis between demand (y in 1000 units) and price (x in dollars) resulted in the following equation y-hat= 9 − 3x The above equation implies that if the price is increased by $1, the demand is expected to
decrease by 3,000 units
In regression analysis, the response variable is the
dependent variable
In the ANOVA, treatment refers to
different levels of a factor
A multiple regression model has the form y-hat= 5 + 6x + 7w As x increases by 1 unit (holding w constant), y is expected to
increase by 6 units
A regression analysis between sales (y in $1000) and advertising (x in dollars) resulted in the following equation y-hat = 50,000 + 6x
increase of $1 in advertising is associated with an increase of $6,000 in sales
A regression analysis between sales (in $1000) and price (in dollars) resulted in the following equation y-hat = 50,000 − 8x The above equation implies that an
increase of $1 in price is associated with a decrease of $8000 in sales
If a qualitative variable has k levels, the number of dummy variables required is
k − 1
A procedure used for finding the equation of a straight line that provides the best approximation for the relationship between the independent and dependent variables is the
least squares method
A least squares regression line
may be used to predict a value of y if the corresponding x value is given
A term used to describe the case when the independent variables in a multiple regression model are correlated is
multicollinearity
A measure of goodness of fit for the estimated regression equation is the
multiple coefficient of determination
The number of degrees of freedom for the appropriate chi-square distribution in a test of independence is
number of rows minus 1 times number of columns minus 1
Regression analysis is a statistical procedure for developing a mathematical equation that describes how
one dependent and one or more independent variables are related
In ANOVA, the dependent variable is also known as the
response variable
The ANOVA procedure is a statistical approach for determining whether or not
the means of two or more populations are equal
The adjusted multiple coefficient of determination is adjusted for
the number of independent variables
As the goodness of fit for the estimated multiple regression equation increases,
the value of the multiple coefficient of determination increases
In multiple regression analysis,
there can be several independent variables, but only one dependent variable
The chi-square test for independence involves
two categorical variables
In ANOVA, which of the following is not affected by whether or not the population means are equal?
within-samples estimate of o^2