1、4. 研究青春发育与远视率(对数视力)的变化关系,测得结果如下表: 年龄(岁) x远视率( %) y对数视力 Y=ln y6 63.64 4.1537 61.06 4.1128 38.84 3.6599 13.75 2.62110 14.50 2.67411 8.07 2.08812 4.41 1.48413 2.27 0.8214 2.09 0.73715 1.02 0.0216 2.51 0.9217 3.12 1.13818 2.98 1.092试建立曲线回归方程 = ( = + )并进行计量分析。yabxeYalnbx4.(1)利用 eviews 可得到建立青春发育与对视力的散点图:0
2、123455 10 15 20XLNY有题意可知青春发育与对视力的回归方程:= +Yalnbx(2)有 eviews 可知各参数为Dependent Variable: LNYMethod: Least SquaresDate: 10/23/12 Time: 16:52Sample: 1 13Included observations: 13Variable Coefficient Std. Error t-Statistic Prob. C 5.730198 0.605700 9.460463 0.0000X -0.313940 0.048187 -6.515044 0.0000R-squa
3、red 0.794184 Mean dependent var 1.962923Adjusted R-squared 0.775473 S.D. dependent var 1.371926S.E. of regression 0.650076 Akaike info criterion 2.117184Sum squared resid 4.648592 Schwarz criterion 2.204100Log likelihood -11.76170 F-statistic 42.44580Durbin-Watson stat 0.662056 Prob(F-statistic) 0.000043Lna=5.730198 a=-0.313940所以 = + =5.730198-0.313940xYalnbx(3)模型检验从回归估计结果看,模型拟合一般, ,t 值为79418.02R9.460463 -6.515044,斜率项为-0.313940,这表明孩子的对数视力随着年龄的增加而呈平均下降趋势。