BUAL 2650- Gramling Exam 2
Questions and Answers
false
Correlation does not assume or imply causation. The correlation coefficient,r,
gives the strength and direction of the relationship between two quantitative
variables. - -A significant positive correlation between X and Y implies that
changes in X cause Y to change.
- monthly advertising expenditures
The variable being used to make a prediction is plotted on the x-axis of the
scatterplot.
The prediction (or response variable) is plotted on the y-axis of the
scatterplot. - -A local tire dealer wants to predict the number of tires sold
each month. He believes that the number of tires sold is a linear function of
the amount of money invested in advertising. He randomly selects 6 months
of data consisting of monthly tire sales (in thousands of tires) and monthly
advertising expenditures (in thousands of dollars). The simple linear
regression equation is ŷ = 3 + 1x. The dealer randomly selects one of the six
observations, with a monthly sales value of 8,000 tires and monthly
advertising expenditures of $7,000. Which variable would be plotted on the X
axis of the scatterplot?
- slope of regression line
The slope can be positive or negative based on the relationship between x
and y. The sign of the slope and the sign of the correlation coefficient, r, are
always the same. - -In simple regression analysis, the quantity that gives the
amount by which Y (dependent variable) changes for a unit change in X
(independent variable) is called the
-0
When x is equal to zero you would expect to get the value of the y intercept
for y. - -In a simple linear regression model, the intercept term is the mean
value of y when x equals ________.
- false
Correlation does not assume or predict causation or direction. The
correlation coefficient,r, gives the strength and direction of the relationship
between two quantitative variables. - -When using simple regression
analysis, if there is a strong correlation between the independent and
, dependent variables, then we can conclude that an increase in the value of
the independent variable causes an increase in the value of the dependent
variable.
- outlier
Outliers are identified as measurements that are widely separated from the
other data measurements. - -An unusually large or small observation
separated from the rest of the data is a(n) ________.
- false
This notation refers to the estimated or predicted value of the dependent
variable. - -The notation Ŷ refers to the average value of the dependent
variable Y.
- y-intercept
When x is equal to 0 you would predict to get the y intercept as your y value.
- -The ________ of the simple linear regression model is the value of y when
the mean value of x is zero.
- True
The independent variable on the x axis while the dependent variable is on
the y axis of a scatterplot. - -A simple linear regression model is an equation
that describes the straight-line relationship between a dependent variable
and an independent variable.
- -2000
residual = observed # tires - predicted # tires
e = y - predicted y - -A local tire dealer wants to predict the monthly sales
for number of tires sold each month. He believes tires sale is a linear
function of the amount of money invested in advertising. He randomly
selects 6 months of data consisting of monthly tire sales and monthly
advertising expenditures. The simple linear regression equation is ŷ = 3000
+ 1x. The dealer randomly selects one of the six observations, with a
monthly sales value of 8,000 tires and monthly advertising expenditures of
$7,000. Calculate the value of the residual for this observation.
- slope of the regression line
The slope can be positive or negative based on the relationship between x
and y. - -In simple regression analysis, the quantity that gives the amount
Questions and Answers
false
Correlation does not assume or imply causation. The correlation coefficient,r,
gives the strength and direction of the relationship between two quantitative
variables. - -A significant positive correlation between X and Y implies that
changes in X cause Y to change.
- monthly advertising expenditures
The variable being used to make a prediction is plotted on the x-axis of the
scatterplot.
The prediction (or response variable) is plotted on the y-axis of the
scatterplot. - -A local tire dealer wants to predict the number of tires sold
each month. He believes that the number of tires sold is a linear function of
the amount of money invested in advertising. He randomly selects 6 months
of data consisting of monthly tire sales (in thousands of tires) and monthly
advertising expenditures (in thousands of dollars). The simple linear
regression equation is ŷ = 3 + 1x. The dealer randomly selects one of the six
observations, with a monthly sales value of 8,000 tires and monthly
advertising expenditures of $7,000. Which variable would be plotted on the X
axis of the scatterplot?
- slope of regression line
The slope can be positive or negative based on the relationship between x
and y. The sign of the slope and the sign of the correlation coefficient, r, are
always the same. - -In simple regression analysis, the quantity that gives the
amount by which Y (dependent variable) changes for a unit change in X
(independent variable) is called the
-0
When x is equal to zero you would expect to get the value of the y intercept
for y. - -In a simple linear regression model, the intercept term is the mean
value of y when x equals ________.
- false
Correlation does not assume or predict causation or direction. The
correlation coefficient,r, gives the strength and direction of the relationship
between two quantitative variables. - -When using simple regression
analysis, if there is a strong correlation between the independent and
, dependent variables, then we can conclude that an increase in the value of
the independent variable causes an increase in the value of the dependent
variable.
- outlier
Outliers are identified as measurements that are widely separated from the
other data measurements. - -An unusually large or small observation
separated from the rest of the data is a(n) ________.
- false
This notation refers to the estimated or predicted value of the dependent
variable. - -The notation Ŷ refers to the average value of the dependent
variable Y.
- y-intercept
When x is equal to 0 you would predict to get the y intercept as your y value.
- -The ________ of the simple linear regression model is the value of y when
the mean value of x is zero.
- True
The independent variable on the x axis while the dependent variable is on
the y axis of a scatterplot. - -A simple linear regression model is an equation
that describes the straight-line relationship between a dependent variable
and an independent variable.
- -2000
residual = observed # tires - predicted # tires
e = y - predicted y - -A local tire dealer wants to predict the monthly sales
for number of tires sold each month. He believes tires sale is a linear
function of the amount of money invested in advertising. He randomly
selects 6 months of data consisting of monthly tire sales and monthly
advertising expenditures. The simple linear regression equation is ŷ = 3000
+ 1x. The dealer randomly selects one of the six observations, with a
monthly sales value of 8,000 tires and monthly advertising expenditures of
$7,000. Calculate the value of the residual for this observation.
- slope of the regression line
The slope can be positive or negative based on the relationship between x
and y. - -In simple regression analysis, the quantity that gives the amount
