Texas Instruments TI-73VSC Guidebook - Page 150

144 Chapter 7: Statistical Analyses 5. View the line on the Graph screen. (7 The Manual-Fit line, Y1 (see example from that section) The LinReg(ax+b) line 6. View the equation stored to Y2, if desired. & Y3 and Y4 may vary. QuadReg - v ! 6 QuadReg (quadratic regression) fits the second-degree polynomial y=ax2+bx+c to the data. It displays values for a, b, and c; when DiagnosticOn is set, it also displays a value for r2 (coefficient of determination). The DiagnosticOn command is in the CATALOG (- |). You can execute the QuadReg command from the Graph screen, the Home screen, or the Program editor. For three data points, the equation is a polynomial fit; for four or more, it is a polynomial regression. At least three data points are required. From the Home screen or the Program editor, QuadReg accepts four optional arguments. Enter up to two list names, XList and YList; a frequency list, freq; and an equation variable, Yn. freq is the frequency of occurrence for each corresponding data point in XList and YList. If freq is omitted, all values are used once. If XList and YList are not specified, the default list names are L1 and L2. To access Yn variables, press - } 2. QuadReg [XList,YList,freq,Yn]