24
Mar
Sample regression function, SRF – 8 min [video, FRM: quant]
by David Harper, CFA, FRM, CIPM
These short videos are partial recordings of practice sessions (i.e., as I practice for a webinar or paid tutorial). I share in case you find them useful.
A brief review of the meaning of the sample regression function (SRF). A few key ideas from Gujarati here:
- As with univariate inferences, we expect sampling fluctuation/variation. In theory, there is one population regression function (PRF) but several sample regression functions (SRF). It is important to see: we assume an unknowable population; we take a sample to learn something about the popluation. As samples vary, so do sample statistics. How to characterize the inevitable variation ("fluctuation" in Gujarati's term)? We can use a distribution to describe (characterize) unavoidable variation in the sample statistic.
- Note the correspondence: the PRF contains population parameters (slope, intercept) while the SRF contains estimators.
- What is linear in linear regression? We require linearity in the parameters (slope, intercept) but we do not require linearity in the variable(s); i.e., X^2 is okay!
Briefcast:
Comments
Great job! Thank you very much!
Leave a Comment