1、一元回歸分析MATLAB的計算利用matlab計算一元回歸分析函數如下所示，根據試驗數據x和y,可在matlab中利 用一元擬合實現回歸直線的計算、相關系數計算、同時得出一個散點圖和回歸直線圖。Matlab程序代碼如下： x=15.0,25.8,30.0,36.6,44.4 y=39.4,42.9,41.0,43.1,49.2 n=1; p=polyfit(x,y,n) xi=linspace(15,45,100) z=polyval(p,xi) plot(x,y,*b,xi,z,r)x，y以數組的形式輸入 擬合階數設置為1 計算擬合系數a，b規定擬合曲線橫軸的分度 虛擬出擬合曲線上的點 畫出

2、散點圖和回歸直線圖 xlabel(x),ylabel(y=0.2924x+34.2417),legend(散點圖和回歸直線)具體程序和程序的執行結果如下所示： x=15.0,25.8,30.0,36.6,44.4=15.000025.800030.000036.600044.4000 y=39.4,42.9,41.0,43.1,49.2y =39.400042.900041.000043.100049.2000 n=1; p=polyfit(x,y,n)P =0.292434.2417 xi=linspace(15,45,100)=15.000015.303015.606115.909116.

3、212116.515216.818217.121217.424217.727318.030318.333318.6364Columns 14 through 2618.939419.242419.545519.848520.151520.454520.757621.060621.363621.666721.969722.272722.5758Columns 27 through 3922.878823.181823.484823.787924.090924.393924.697025.000025.303025.606125.909126.212126.5152Columns 40 throu

4、gh 5226.818227.121227.424227.727328.030328.333328.636428.939429.242429.545529.848530.151530.4545Columns 53 through 6530.757631.060631.363631.666731.969732.272732.575832.878833.181833.484833.787934.090934.3939Columns 66 through 7834.697035.000035.303035.606135.909136.212136.515236.818237.121237.42423

5、7.727338.030338.3333Columns 79 through 9138.636438.939439.242439.545539.848540.151540.454540.757641.060641.363641.666741.969742.2727Columns 92 through 10042.575842.878843.181843.484843.787944.090944.393944.697045.0000 z=polyval(p,xi)z =38.628238.716838.805538.894138.982739.071339.159939.248539.33723

6、9.425839.514439.603039.6916Columns 14 through 2639.780239.868839.957540.046140.134740.223340.311940.400540.489240.577840.666440.755040.8436Columns 27 through 3940.932241.020941.109541.198141.286741.375341.463941.552641.641241.729841.818441.907041.9956Columns 40 through 5242.084342.172942.261542.3501

7、42.438742.527342.616042.704642.793242.881842.970443.059043.1476Columns 53 through 6543.236343.324943.413543.502143.590743.679343.768043.856643.945244.033844.122444.211044.2997Columns 66 through 7844.388344.476944.565544.654144.742744.831444.920045.008645.097245.185845.274445.363145.4517Columns 79 th

8、rough 9145.540345.628945.717545.806145.894845.983446.072046.160646.249246.337846.426446.515146.6037Columns 92 through 10046.692346.780946.869546.958147.046847.135447.224047.312647.4012 plot(x,y,*b,xi,z,r:) plot(x,y,*b,xi,z,r) xlabel(x),ylabel(y=0.2924x+34.2417),legend(散點圖和回歸直線)散點圖:45405 330Xzgcm.pco

9、+xw&olFile Edit View Insert Tools Desktop Window Help辦 MATLABFile Edit Debug Desktop Window Help芽 |X g c|U 呼 | Current Directory: | C:)MATLAB7work三|也|Shortcuts 回 How to Add 回 Whats New x=15. 0, 25. 8, 30. 0, 36. 6,44.4; y=39.4,42. 9,41. 0,43. 1,49. 2; n=l; p=polyfit (x, y, n)P =0.292434.2417 xi=linspace (15,45, 100); z=p