Chapter 10 Flashcards
Variation in Y
Definition - Simple linear Regression
Explains variation in a DEPENDENT variable in terms of the variation in a SINGLE INDEPDENT variable.
Definition - Dependent
variable whos variation is explained by the independent variable.
EXPLAINED variable or the predicted variable.
Definition - Independent
variable used to explain the variation of the dependent variable.
Ordinary Least Squared Line
Error Term
Intercept Interpretation for ABC stock excess return of -2.3
Slope interpretation for ABC stock excess return of 0.64%
What does it mean when variable have a hat ?
Hat means predicted value
Slope Coefficient
Intercept
Regression l ine passes through (Xbar,Ybar)
Assumption of linear Regression
(1) Linear relationship with dep and indep
(2) Variance of error terms is constant (homoskedasticity)
(3) Error terms are independently distributed (i.e. uncorrelated with each other)
(4) Error terms are normally distributed.
Violation of 3 and/or 4 is called serial of auto-correlation.
homoskedasticity
case where prediction errors all have the same constant variance
hetroskedasticity
variance of the error terms not being constant.
total sum of squares (SST)