BUS Analytics Exam 1

Prediction of the value of the dependent variable outside the experimental region is called

extrapolation

In the graph of the simple linear regression equation, the parameter ß1 is the ___________ of the true regression line.

slope

In a simple linear regression analysis the quantity that gives the amount by which the dependent variable changes for a unit change in the independent variable is called the

slope of the regression line

In a simple linear regression model, y = ß0 + ß1x + ε the parameter ß1 represents the

slope of the true regression line

The least squares regression line minimizes the sum of the

squared differences between actual and predicted y values

The graph of the simple linear regression equation is a(n)

straight line

The population parameters that describe the y-intercept and slope of the line relating y and x, respectively, are

ß0 and ß1

The scatter chart below displays the residuals versus the dependent variable, x. Which of the following conclusions can be drawn based upon this scatter chart?

The residual distribution is not normally distributed.

HW 3 #9 The scatter chart below displays the residuals versus the dependent variable, x. Which of the following conclusions can be drawn from the scatter chart given below?

The residuals have an increasing variance as the dependent variable increases.

Fitting a model too closely to sample data, resulting in a model that does not accurately reflect the population is termed as

overfitting

If covariance between two variables is near 0, it implies that

the variables are not linearly related

__________ refers to the data set used to compare model forecasts and ultimately pick a model for predicting values of the dependent variable.

validation set

In the graph of the simple linear regression equation, the parameter ß0 represents the ___________ of the true regression line.

y-intercept

When the mean value of the dependent variable is independent of variation in the independent variable, the slope of the regression line is

zero

The correlation coefficient will always take values

between -1 and +1

In a linear regression model, the variable that is being predicted or explained is known as _____________. It is denoted by y and is often referred to as the response variable.

dependent variable

A variable used to model the effect of categorical independent variables in a regression model is known as a

dummy variable

__________ is the data set used to build the candidate models.

training set

The coefficient of determination

is used to evaluate the goodness of fit

What would be the coefficient of determination if the total sum of squares (SST) is 23.29 and the sum of squares due to regression (SSR) is 10.03?

.43

What would be the value of the sum of squares due to regression (SSR) if the total sum of squares (SST) is 25.32 and the sum of squares due to error (SSE) is 6.89?

18.43

__________ is used to test the hypothesis that the values of the regression parameters ß1, ß2, ... ßq are all zero.

An F test

The scatter chart below displays the residuals versus the dependent variable, x. Which of the following conclusions can be drawn based upon this scatter chart?

The model fails to capture the relationship between the variables accurately.

A variable used to model the effect of categorical independent variables in a regression model which generally takes only the value zero or one is called

a dummy variable

The ___________ is a measure of the goodness of fit of the estimated regression equation. It can be interpreted as the proportion of the variability in the dependent variable y that is explained by the estimated regression equation.

coefficient of determination

The __________ is an indication of how frequently interval estimates based on samples of the same size taken from the same population using identical sampling techniques will contain the true value of the parameter we are estimating.

confidence level

Assessing the regression model on data other than the sample data that was used to generate the model is known as

cross-validation

In the simple linear regression model, the ____________ accounts for the variability in the dependent variable that cannot be explained by the linear relationship between the variables.

error team

Prediction of the mean value of the dependent variable y for values of the independent variables x1, x2, . . . , xq that are outside the experimental range is called

extrapolation

In a linear regression model, the variable (or variables) used for predicting or explaining values of the response variable are known as the __________. It(they) is(are) denoted by x.

independent variable

__________ refers to the scenario in which the relationship between the dependent variable and one independent variable is different at different values of a second independent variable.

interaction

The prespecified value of the independent variable at which its relationship with the dependent variable changes in a piecewise linear regression model is referred to as the

knot

The degree of correlation among independent variables in a regression model is called

multicollinearity

__________ refers to the degree of correlation among independent variables in a regression model.

multicollinearity

Regression analysis involving one dependent variable and more than one independent variable is known as

multiple regression

Which of the following regression models is used to model a nonlinear relationship between the independent and dependent variables by including the independent variable and the square of the independent variable in the model?

quadratic regression model

__________ is a statistical procedure used to develop an equation showing how two variables are related.

regression analysis

The difference between the observed value of the dependent variable and the value predicted using the estimated regression equation is known as the

residual

A _____________ is a graphical presentation of the relationship between two quantitative variables.

scatter chart

A __________ is used to visualize sample data graphically and to draw preliminary conclusions about the possible relationship between the variables.

scatter plot

A regression analysis involving one independent variable and one dependent variable is referred to as a

simple linear regression

The __________ is a measure of the error that results from using the estimated regression equation to predict the values of the dependent variable in the sample.

sum of squares due to error (SSE)

Which of the following relationships would have a negative correlation coefficient?

supply and demand

A procedure for using sample data to find the estimated regression equation is

the least squares method