Texas Instruments TI-84 PLUS Guidebook - Page 391

• ZXmin, ZXmax, ZXscl, ZTstep, ZPlotStart, Zu(nMin), and other ZOOM variables. The variables below are reserved for use by the TI-84 Plus. You cannot store to them. n, v, Sx, sx, minX, maxX, Gy, Gy2, Gxy, a, b, c, RegEQ, x1, x2, y1, z, t, F, c2, Ç, v1, Sx1, n1, lower, upper, r2, R2 and other statistical variables. Statistics Formulas This section contains statistics formulas for the Logistic and SinReg regressions, ANOVA, 2-SampÜTest, and 2-SampTTest. Logistic The logistic regression algorithm applies nonlinear recursive least-squares techniques to optimize the following cost function: ∑ J = i N = 1 ⎛ ⎜ ⎝ -----------c------------ 1 + a -b e xi - ⎞ yi⎠⎟ 2 which is the sum of the squares of the residual errors, where: x = the independent variable list y = the dependent variable list N = the dimension of the lists This technique attempts to estimate the constants a, b, and c recursively to make J as small as possible. SinReg The sine regression algorithm applies nonlinear recursive least-squares techniques to optimize the following cost function: N ∑ J = [a sin(bxi + c) + d - yi]2 i=1 which is the sum of the squares of the residual errors, where: x = the independent variable list y = the dependent variable list N = the dimension of the lists This technique attempts to recursively estimate the constants a, b, c, and d to make J as small as possible. Appendix B: Reference Information 384