Linear Regression and Correlation: Prediction 1.5 2008/06/23 16:50:21 GMT-5 2008/07/15 13:55:22.098 GMT-5 Barbara Illowsky illowskybarbara@deanza.edu Susan Dean deansusan@deanza.edu Connexions cnx@cnx.org elementary statistics This module provides an overview of Linear Regression and Correlation: Prediction Up one level as a part of Collaborative Statistics collection (col10522) by Barbara Illowsky and Susan Dean. The exam scores (x-values) range from 65 to 75. Suppose you want to know the final exam score of statistics students who received 73 on the third exam. Since 73 is between the x-values 65 and 75, substitute x=73 into the equation. Then: y ^ = -173.51 + 4.83 ( 73 ) = 179.08 We predict that a statistics student who receives a 73 on the third exam will receive 179.08 on the final exam. Remember, do not use the regression equation to predict values outside the domain of x.Recall the third exam/final exam example. What would you predict the final exam score to be for a student who scored a 66 on the third exam? 145.27 What would you predict the final exam score to be for a student who scored a 78 on the third exam? 78 is outside of the domain of x values (independent variables), so you cannot reliably predict the final exam score for this student.