STAT310 EXAM TERMINOLOGY QUESTIONS
AND CORRECT DETAILED ANSWERS (VERIFIED
ANSWERS) ||ALREADY GRADED A+||NEWEST
VERSION
Quiz: How are parameters estimated for linear regression?
Ans: Method of least squares
Quiz: What is the multiple linear regression model?
Ans: Yi = B0 + B1Xi1 + ... + BpXip + ei
ei are random errors
Yi is the response for the ith case
There are p predictor variables x1, x2, ..., xp
Quiz: Least square estimates
Ans: Minimizes sum of squares
Quiz: Residual
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, Ans: Actual - Predicted value
Quiz: Residual sum of squares
Ans: sum of residuals squared (Yi - mu hat)^2 summed together
We want small RSS to indicate a better model (minimize SS)
Quiz: Factor
Ans: Is a categorical variable that can be incorporated into regression models
by dummy variables. Factors with k levels are coded with k-1 variables since one
level is the reference level
Quiz: What is matrix formulation of the linear model?
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, Ans: Y = XB + e
- Y is the response vector
- X is the design matrix
- B is the vector of p+1 (including intercept) regression parameters
- e is the vector of error terms
Ex: Y = [Y1, Y2....]
B = [B0, B1, ...]
E = [e1, e2,...]
Quiz: F-test hypotheses
Ans: Ho: response is not related to any of the predictors
Ha: response y is related to at least one of the predictors in the model
Quiz: Bias-Variance tradeoff
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me in the number given.
, Ans: As complexity in model increases (more predictors), bias decreases but
variance increases
- We want to control both bias and variance
Quiz: Bias
Ans: Bias(μˆ) = E[μˆ] − μ
Bias arises because of the model misspecification (banana shape but fit a linear
regression) WRONG MODEL
Quiz: Variance
Ans: Var(μˆ) = SE(μˆ)^2
Arises due to noise in estimating regression coefficients
Quiz: Mean squared error (MSE)
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me in the number given.
AND CORRECT DETAILED ANSWERS (VERIFIED
ANSWERS) ||ALREADY GRADED A+||NEWEST
VERSION
Quiz: How are parameters estimated for linear regression?
Ans: Method of least squares
Quiz: What is the multiple linear regression model?
Ans: Yi = B0 + B1Xi1 + ... + BpXip + ei
ei are random errors
Yi is the response for the ith case
There are p predictor variables x1, x2, ..., xp
Quiz: Least square estimates
Ans: Minimizes sum of squares
Quiz: Residual
o
o
© 2025 TestTrackers
WhatsApp or call o Resources & Updates: [Testtrackers - Stuvia US]
o Your Success is Our Mission!
[+254707240657]
o For online exams and tutor expert, please whatsapp
me in the number given.
, Ans: Actual - Predicted value
Quiz: Residual sum of squares
Ans: sum of residuals squared (Yi - mu hat)^2 summed together
We want small RSS to indicate a better model (minimize SS)
Quiz: Factor
Ans: Is a categorical variable that can be incorporated into regression models
by dummy variables. Factors with k levels are coded with k-1 variables since one
level is the reference level
Quiz: What is matrix formulation of the linear model?
o
o
© 2025 TestTrackers
WhatsApp or call o Resources & Updates: [Testtrackers - Stuvia US]
o Your Success is Our Mission!
[+254707240657]
o For online exams and tutor expert, please whatsapp
me in the number given.
, Ans: Y = XB + e
- Y is the response vector
- X is the design matrix
- B is the vector of p+1 (including intercept) regression parameters
- e is the vector of error terms
Ex: Y = [Y1, Y2....]
B = [B0, B1, ...]
E = [e1, e2,...]
Quiz: F-test hypotheses
Ans: Ho: response is not related to any of the predictors
Ha: response y is related to at least one of the predictors in the model
Quiz: Bias-Variance tradeoff
o
o
© 2025 TestTrackers
WhatsApp or call o Resources & Updates: [Testtrackers - Stuvia US]
o Your Success is Our Mission!
[+254707240657]
o For online exams and tutor expert, please whatsapp
me in the number given.
, Ans: As complexity in model increases (more predictors), bias decreases but
variance increases
- We want to control both bias and variance
Quiz: Bias
Ans: Bias(μˆ) = E[μˆ] − μ
Bias arises because of the model misspecification (banana shape but fit a linear
regression) WRONG MODEL
Quiz: Variance
Ans: Var(μˆ) = SE(μˆ)^2
Arises due to noise in estimating regression coefficients
Quiz: Mean squared error (MSE)
o
o
© 2025 TestTrackers
WhatsApp or call o Resources & Updates: [Testtrackers - Stuvia US]
o Your Success is Our Mission!
[+254707240657]
o For online exams and tutor expert, please whatsapp
me in the number given.
