5.2 The Population Regression Function(PRF) a1. Population Regression Line(PRL) 0 PRI a line that tells us how the average/mean value of y (or any dependent variable)is related to each value of X(or any independent variable). a line that passes through the conditional means ofY D E(YXI)=B1+B2Xi (5.1) E(YXI: the mean, orexpected, value of Y corresponding to, or conditional upon, a given value of X. conditional expectation or conditional expected value ofy BI and B2: the parameters, the regression coefficients Bl: the intercept(coefficient) B2: the slope(coefficient) The slope coefficient measures the rate of change in the(conditional) mean value of Y per unit change inⅩ
5.2 The Population Regression Function(PRF) 1.Population Regression Line (PRL) PRL——a line that tells us how the average/mean value of Y (or any dependent variable) is related to each value of X(or any independent variable)． ——a line that passes through the conditional means of Y． E(Y|Xi) = B1+B2Xi (5.1) E(Y|Xi):the mean，or expected，value of Y corresponding to，or conditional upon，a given value of X． ～conditional expectation or conditional expected value of Y． B1 and B2: the parameters, the regression coefficients． B1: the intercept (coefficient) B2: the slope (coefficient)．—— The slope coefficient measures the rate of change in the (conditional) mean value of Y per unit change in X．
5.2 The Population Regression Function(PRF) a Population Regression Function (PRF) E(Xi)=B+B2Xi m Note: Usually expressions like E(YXi is simply written as E(Y), with the explicit understanding that the latter in fact stands for the former
2. Population Regression Function（PRF） E(Y|Xi) = B1+B2Xi 3. Note: Usually expressions like E(Y|Xi) is simply written as E(Y)，with the explicit understanding that the latter in fact stands for the former． 5.2 The Population Regression Function(PRF)