STAT 101 Chapter Notes - Chapter 5: Dependent And Independent Variables, Total Variation, Standard Deviation

• School: Simon Fraser University
• Department: Statistics
• Course: STAT 101
• Professor: Qian( Michelle) Zhou

Document Summary

= r(sy/sx) also known as rate of change . Refer to figure 5. 1. x is non exercise activity and y is fat gain. B = -0. 00344 a = 3. 505 it"s the predicted fat gain when x is 0. Fat gain = a + (b x non-exercise activity change) Fat gain = 3. 505 0. 00344 x nea change. Facts about least-squares regression: distinction b/w explanatory and response variable is essential in regression, slope and correlation always have same sign. If scatterplot has positive association, b and r are both positive. If r=1 or -1, change in predicted response, , is same (in standard deviation units) as change in x. Residuals residuals difference b/w observed value for y and value predicted by regression line. It"s a prediction error that remains after we have chose the regression line: residual = observed y predicted y. Example 5. 5 i feel your pain) r = 0. 515.