PSY201 Exam 3: Regression Study
Guide Questions All Answered Correct
2025/2026 Updated.
what is the purpose of the regression line? - Answer -makes the relationship easier to see
-identifies the center of the relationship
-can be used for prediction
The equation of the regression line has the general form: - Answer y = a + bx
what is 'a' in the equation? - Answer -the intercept
-represents the overall height of the line in terms of the point at which the line crosses the y-
axis
what is 'b' in the equation? - Answer -the slope
-regression coefficient (weight); reflects the rate at which values of y are changing for a unit
change in x
what is residuals accounted for? - Answer the space between predicted and actual point
what is variance accounted for? - Answer how much changes in x causes the changes in y
fitted value - Answer ŷ
residual - Answer y-ŷ
assumptions of regression analysis - Answer -each of the conditional distributions is a
sample from a normally distributed random variable
-normal distributions have the same variance
assumptions of linear regression - Answer -the population means of the conditional
distributions lie along a straight line, called a regression line
, y- dv
what are a and variance? - Answer parameters that define the regression line
what is b? - Answer -positive if the relationship is positive and the line will go up
-negative if the relationship is negative and the line will go down
what would happen if there was no relationship between x and y? - Answer b would be 0
what is the standard error of the estimate? - Answer -it gives a measure of the standard
distance between a regression line and the actual data points
what is the formula of standard error of the estimate? - Answer √SS error √Σ(y-ŷ)²
----------- = --------------
df n-2
difference between regression equation and standard error of the estimate? - Answer -
regression lets us make a prediction
-standard error of the estimate gives us the actual data points
how to interpret slope? - Answer "for each (unit of x) change in (x), (y) increases/decreases
by (absolute value of slope) (units of y)."
-ex. for each one point change in anxiety score, test score decreases by .9 points.
an educator wants to predict college gpa from sat math scores and obtains this regression
equation:
y' = .003x + 1.7 - Answer for each 1 point increase in the sat math scores, the college gpa will
go up by .003 points
a researcher wants to predict happiness (rated on a 1-10 scale) from people's hourly salary (in
Guide Questions All Answered Correct
2025/2026 Updated.
what is the purpose of the regression line? - Answer -makes the relationship easier to see
-identifies the center of the relationship
-can be used for prediction
The equation of the regression line has the general form: - Answer y = a + bx
what is 'a' in the equation? - Answer -the intercept
-represents the overall height of the line in terms of the point at which the line crosses the y-
axis
what is 'b' in the equation? - Answer -the slope
-regression coefficient (weight); reflects the rate at which values of y are changing for a unit
change in x
what is residuals accounted for? - Answer the space between predicted and actual point
what is variance accounted for? - Answer how much changes in x causes the changes in y
fitted value - Answer ŷ
residual - Answer y-ŷ
assumptions of regression analysis - Answer -each of the conditional distributions is a
sample from a normally distributed random variable
-normal distributions have the same variance
assumptions of linear regression - Answer -the population means of the conditional
distributions lie along a straight line, called a regression line
, y- dv
what are a and variance? - Answer parameters that define the regression line
what is b? - Answer -positive if the relationship is positive and the line will go up
-negative if the relationship is negative and the line will go down
what would happen if there was no relationship between x and y? - Answer b would be 0
what is the standard error of the estimate? - Answer -it gives a measure of the standard
distance between a regression line and the actual data points
what is the formula of standard error of the estimate? - Answer √SS error √Σ(y-ŷ)²
----------- = --------------
df n-2
difference between regression equation and standard error of the estimate? - Answer -
regression lets us make a prediction
-standard error of the estimate gives us the actual data points
how to interpret slope? - Answer "for each (unit of x) change in (x), (y) increases/decreases
by (absolute value of slope) (units of y)."
-ex. for each one point change in anxiety score, test score decreases by .9 points.
an educator wants to predict college gpa from sat math scores and obtains this regression
equation:
y' = .003x + 1.7 - Answer for each 1 point increase in the sat math scores, the college gpa will
go up by .003 points
a researcher wants to predict happiness (rated on a 1-10 scale) from people's hourly salary (in
