計量實習(xí)報告
發(fā)布時間:2020-08-11 來源: 講話發(fā)言 點擊:
2009-2010
學(xué)年度第
2
學(xué)期
計量經(jīng)濟學(xué)實驗報告書
專
業(yè)
金融學(xué)
班
級
三班
學(xué)
號
6
學(xué)生姓名
經(jīng)濟與貿(mào)易學(xué)院
實驗一
Eviews 基本操作實驗
一、實驗?zāi)康模赫莆?Eviews 基本操作 。
二、實驗要求:
。1)
EViews 軟件的安裝; (2)
數(shù)據(jù)的輸入、編輯與序列生成; (3)
圖形分析與描述統(tǒng)計分析; (4)
數(shù)據(jù)文件的存貯、調(diào)用與轉(zhuǎn)換。
三 、實驗結(jié)果報告:
(圍繞實驗要求,結(jié)合實驗的內(nèi)容撰寫報告)
一、數(shù)據(jù)的輸入、序列生成
二、圖形分析
obs Y X 1985 2041 8964 1986 2091 10202 1987 2140 11963 1988 2391 14928 1989 2727 16909 1990 2822 18548 1991 2990 21618 1992 3297 26638 1993 4255 34634 1994 5127 46759 1995 6038 58478 1996 6910 67885 1997 8234 74463 1998 9263 79396
與 以上可以看出我國稅收與 GDP 呈線性遞增關(guān)系 系
obs T X X1 X2 1985 1 8964
0.0473 1986 2 10202 104080804 9.80199960792e-05 1987 3 11963 143113369 8.35910724735e-05 1988 4 14928 222845184 6.6988210075e-05 1989 5 16909 285914281 5.91401029038e-05 1990 6 18548 344028304 5.39141686435e-05 1991 7 21618 467337924 4.62577481728e-05 1992 8 26638 709583044 3.75403558826e-05 1993 9 34634 1199513956 2.88733614367e-05 1994 10 46759 2186404081 2.e-05 1995 11 58478 3419676484 1.71004480317e-05 1996 12 67885 4608373225 1.47307947264e-05 1997 13 74463 5544738369 1.34294884708e-05 1998 14 79396 6303724816 1.25950929518e-05
Y X
Mean
4309.000
35098.93
Median
3143.500
24128.00
Maximum
9263.000
79396.00
Minimum
2041.000
8964.000
Std. Dev.
2422.631
25378.06
Skewness
0.869889
0.635116
Kurtosis
2.396109
1.847265
Jarque-Bera
1.978382
1.716333
Probability
0.371877
0.423939
Observations 14 14
實驗二
一元線性回歸分析過程實驗
一、實驗?zāi)康模赫莆找辉性回歸模型的估計方法、檢驗方法和預(yù)測方法。
二、實驗要求:
(1)會選擇方程進行一元線性回歸; (2)掌握一元回歸分析過程; (3)掌握一元回歸模型的基本檢驗方法; (4)會對回歸方程進行經(jīng)濟學(xué)解釋
(5)估計非線性回歸模型,并進行模型比較 三 、實驗結(jié)果報告:
。▏@實驗要求,結(jié)合實驗的內(nèi)容撰寫報告)
一、
圖形分析
兩變量趨勢圖分析結(jié)果顯示,我國稅收收入與 GDP 二者存在差距逐漸增大的增長趨勢。相關(guān)圖分析顯示,我國稅收收入增長與 GDP 密切相關(guān),二者為非線性的曲線相關(guān)關(guān)系。
與 我國稅收與 GDP 的相關(guān)圖 二、估計一元線性回歸模型 Dependent Variable: Y Method: Least Squares Date: 06/22/10
Time: 19:29 Sample: 1985 1998 Included observations: 14 Variable Coefficient Std. Error t-Statistic Prob.
C 987.5417 155.1430 6.365364 0.0000 GDP 0.094631 0.003627 26.09310 0.0000 R-squared 0.982680
Mean dependent var 4309.000 Adjusted R-squared 0.981237
S.D. dependent var 2422.631 S.E. of regression 331.8482
Akaike info criterion 14.57880 Sum squared resid 1321479.
Schwarz criterion 14.67009 Log likelihood -100.0516
F-statistic 680.8498 Durbin-Watson stat 0.796256
Prob(F-statistic) 0.000000 Y=987.54+0.095GDP R^2=0.983
(6.37)
(26.09) 二、
估計非線性回歸模型
1 、 雙對數(shù)模型 Dependent Variable: LOG(Y) Method: Least Squares Date: 06/22/10
Time: 19:45 Sample: 1985 1998 Included observations: 14 Variable Coefficient Std. Error t-Statistic Prob.
C 1.270443 0.331668 3.830470 0.0024 LOG(GDP) 0.682297 0.032415 21.04866 0.0000
R-squared 0.973629
Mean dependent var 8.233505 Adjusted R-squared 0.971431
S.D. dependent var 0.528347 S.E. of regression 0.089302
Akaike info criterion -1.862014 Sum squared resid 0.095699
Schwarz criterion -1.770720 Log likelihood 15.03409
F-statistic 443.0462 Durbin-Watson stat 0.476382
Prob(F-statistic) 0.000000 LOG (Y )=1.27+0.68LOG(GDP)
R^2=0.97
(3.83)
(21.05) 2 、對數(shù)模型 Dependent Variable: Y Method: Least Squares Date: 06/22/10
Time: 19:50 Sample: 1985 1998 Included observations: 14 Variable Coefficient Std. Error t-Statistic Prob.
C -26163.32 3149.684 -8.306649 0.0000 LOG(GDP) 2985.923 307.8313 9.699870 0.0000 R-squared 0.886886
Mean dependent var 4309.000 Adjusted R-squared 0.877460
S.D. dependent var 2422.631 S.E. of regression 848.0607
Akaike info criterion 16.45535 Sum squared resid 8630484.
Schwarz criterion 16.54664 Log likelihood -113.1874
F-statistic 94.08748 Durbin-Watson stat 0.318941
Prob(F-statistic) 0.000000 Y=-26163.32+2985.92LOG(GDP) R^2=0.887
(-8.31)
(9.7) 3 、指數(shù)模型
Dependent Variable: LOG(Y) Method: Least Squares Date: 06/22/10
Time: 19:55 Sample: 1985 1998 Included observations: 14 Variable Coefficient Std. Error t-Statistic Prob.
C 7.508605 0.032400 231.7463 0.0000 GDP 2.07E-05 7.57E-07 27.26846 0.0000 R-squared 0.984118
Mean dependent var 8.233505 Adjusted R-squared 0.982794
S.D. dependent var 0.528347 S.E. of regression 0.069303
Akaike info criterion -2.369086
Sum squared resid 0.057635
Schwarz criterion -2.277792 Log likelihood 18.58360
F-statistic 743.5689 Durbin-Watson stat 0.600192
Prob(F-statistic) 0.000000
4 、二次模型
Dependent Variable: Y Method: Least Squares Date: 06/22/10
Time: 19:59 Sample: 1985 1998 Included observations: 14 Variable Coefficient Std. Error t-Statistic Prob.
C 2323.813 114.4226 20.30904 0.0000 GDP^2 1.08E-06 4.07E-08 26.65249 0.0000 R-squared 0.983388
Mean dependent var 4309.000 Adjusted R-squared 0.982003
S.D. dependent var 2422.631 S.E. of regression 325.0002
Akaike info criterion 14.53709 Sum squared resid 1267502.
Schwarz criterion 14.62839 Log likelihood -99.75965
F-statistic 710.3550 Durbin-Watson stat 0.645855
Prob(F-statistic) 0.000000 四、模型比較 (以二次模型、指數(shù)模型為例)
二次函數(shù)回歸模型殘差分別表
指數(shù)函數(shù)模型殘差分布表
實驗三
多元線性回歸模型
一、實驗?zāi)康模赫莆斩嘣性回歸模型的估計和檢驗方法。
二、實驗要求:
(1)會選擇方程進行多元線性回歸; (2)掌握多元回歸分析過程;
(3)掌握多元回歸模型的基本檢驗方法;
(4)會對回歸方程進行經(jīng)濟學(xué)解釋。
(5)比較選擇最佳模型 三 、實驗結(jié)果報告:
。▏@實驗要求,結(jié)合實驗的內(nèi)容撰寫報告)
一、
多元線 性回歸模型的建立
Dependent Variable: Y
Method: Least Squares Date: 06/22/10
Time: 20:30 Sample: 1978 1994 Included observations: 17 Variable Coefficient Std. Error t-Statistic Prob.
C -675.3208 2682.060 -0.251792 0.8051 T 77.67893 115.6731 0.671538 0.5136 L 0.666665 0.853626 0.780980 0.4488 K 0.776417 0.104459 7.432745 0.0000 R-squared 0.995764
Mean dependent var 6407.249 Adjusted R-squared 0.994786
S.D. dependent var 2486.742 S.E. of regression 179.5630
Akaike info criterion 13.42125 Sum squared resid 419157.5
Schwarz criterion 13.61730 Log likelihood -110.0807
F-statistic 1018.551 Durbin-Watson stat 1.510903
Prob(F-statistic) 0.000000
因此,我國國有獨立工業(yè)企業(yè)的生產(chǎn)函數(shù)為:
K L t y 7764 . 0 6667 . 0 6789 . 77 32 . 675 ˆ ? ? ? ? ?
(模型 1)
t =(-0.252) (0.672)
(0.781)
(7.433) 9958 . 02? R
9948 . 02? R
551 . 1018 ? F
9958 . 02? R ,說明模型有很高的擬合優(yōu)度,F(xiàn) 檢驗也是高度顯著的,說明職工人數(shù) L、資金 K 和時間變量 t 對工業(yè)總產(chǎn)值的總影響是顯著的。但是,模型中其他變量(包括常數(shù)項)的 t 統(tǒng)計量值都較小,未通過檢驗。因此需要做適當(dāng)?shù)恼{(diào)整。
二、建立剔除時間變量的二元線性回歸模型 Dependent Variable: Y Method: Least Squares Date: 06/22/10
Time: 20:36 Sample: 1978 1994 Included observations: 17 Variable Coefficient Std. Error t-Statistic Prob.
C -2387.269 816.8895 -2.922390 0.0111 L 1.208532 0.273020 4.426528 0.0006 K 0.834496 0.057421 14.53287 0.0000 R-squared 0.995617
Mean dependent var 6407.249 Adjusted R-squared 0.994990
S.D. dependent var 2486.742 S.E. of regression 176.0069
Akaike info criterion 13.33771 Sum squared resid 433697.8
Schwarz criterion 13.48475 Log likelihood -110.3705
F-statistic 1589.953 Durbin-Watson stat 1.481994
Prob(F-statistic) 0.000000
此時我國國有獨立工業(yè)企業(yè)的生產(chǎn)函數(shù)為:
K L y 8345 . 0 2085 . 1 27 . 2387 ˆ ? ? ? ?
(模型 2)
t =(-2.922)
(4.427) (14.533) 9956 . 02? R
9950 . 02? R
953 . 1589 ? F
模型 2 的擬合優(yōu)度較模型 1 并無多大變化,F(xiàn) 檢驗也是高度顯著的。但這里,解釋變量、常數(shù)項的 t 檢驗值都比較大,顯著性概率都小于 0.05,因此模型 2 較模型 1 更為合理。
三、建立非線性回歸模型 ——C C- -D D 生產(chǎn)函數(shù)
Dependent Variable: LNY Method: Least Squares Date: 06/22/10
Time: 20:42 Sample: 1978 1994 Included observations: 17 Variable Coefficient Std. Error t-Statistic Prob.
C -1.951253 1.665320 -1.171698 0.2609 LNL 0.604467 0.272697 2.216625 0.0437 LNK 0.673658 0.072357 9.310131 0.0000 R-squared 0.995753
Mean dependent var 8.692837 Adjusted R-squared 0.995147
S.D. dependent var 0.394921 S.E. of regression 0.027512
Akaike info criterion -4.189602 Sum squared resid 0.010597
Schwarz criterion -4.042564 Log likelihood 38.61162
F-statistic 1641.407 Durbin-Watson stat 1.338201
Prob(F-statistic) 0.000000
C-D 生產(chǎn)函數(shù)的估計式為:
K L y ln 6737 . 0 ln 6045 . 0 9513 . 1 ˆ ln ? ? ? ?
。P 3)
t =
(-1.172)
(2.217)
(9.310) 9958 . 02? R
9951 . 02? R
407 . 1641 ? F
從模型 3 中看出,資本與勞動的產(chǎn)出彈性都是在 0 到 1 之間,模型的經(jīng)濟意義合理,而且擬合優(yōu)度較模型 2 還略有提高,解釋變量都通過了顯著性檢驗。
實驗四
異方差模擬實驗
一、實驗?zāi)康模毫私猱惙讲钅P偷臋z驗方法和異方差模型的處理方法。
二、實驗要求:
。1)模擬線性回歸模型中隨機擾動項為異方差的樣本數(shù)據(jù) (2)進行 Goldfeld-Quandt 檢驗 (3)利用 WLS 方法進行參數(shù)估計,建立模型。
三 、實驗結(jié)果報告:
。▏@實驗要求,結(jié)合實驗的內(nèi)容撰寫報告)
一、人均消費與人均收入 Dependent Variable: Y Method: Least Squares Date: 06/23/10
Time: 19:15 Sample: 1 27 Included observations: 27 Variable Coefficient Std. Error t-Statistic Prob.
C 15.83853 9.416160 1.682058 0.1050 X 0.103854 0.011149 9.314931 0.0000 R-squared 0.776322
Mean dependent var 94.44444 Adjusted R-squared 0.767375
S.D. dependent var 45.00712 S.E. of regression 21.70747
Akaike info criterion 9.064377 Sum squared resid 11780.36
Schwarz criterion 9.160365 Log likelihood -120.3691
F-statistic 86.76793 Durbin-Watson stat 2.614427
Prob(F-statistic) 0.000000 Y=15.84+0.104X R^2=0.78
T 統(tǒng)計
1.68
9.31
F=86.77 戈德菲爾德—匡特法(雙變量模型)檢驗 前 前 1-10 個數(shù)據(jù)的回歸 Dependent Variable: Y Method: Least Squares Date: 06/23/10
Time: 20:18 Sample: 1 10 Included observations: 10 Variable Coefficient Std. Error t-Statistic Prob.
C -3.121210 10.53931 -0.296149 0.7747 X 0.144960 0.026196 5.533703 0.0006 R-squared 0.792863
Mean dependent var 52.50000
Adjusted R-squared 0.766971
S.D. dependent var 20.76455 S.E. of regression 10.02368
Akaike info criterion 7.624634 Sum squared resid 803.7933
Schwarz criterion 7.685151 Log likelihood -36.12317
F-statistic 30.62187 Durbin-Watson stat 2.703606
Prob(F-statistic) 0.000551 RSS1=803.79 后 后 10 個數(shù)據(jù)的回歸 Dependent Variable: Y Method: Least Squares Date: 06/23/10
Time: 20:20 Sample: 18 27 Included observations: 10 Variable Coefficient Std. Error t-Statistic Prob.
C 48.41870 56.70995 0.853795 0.4180 X 0.075211 0.047631 1.579027 0.1530 R-squared 0.237611
Mean dependent var 136.4000 Adjusted R-squared 0.142312
S.D. dependent var 36.04688 S.E. of regression 33.38354
Akaike info criterion 10.03086 Sum squared resid 8915.686
Schwarz criterion 10.09138 Log likelihood -48.15430
F-statistic 2.493326 Durbin-Watson stat 2.988119
Prob(F-statistic) 0.152983
RSS2=8915.69 RSS2/RSS1= 11.09>F(8,8)=3.44 所以存在異方差 用 利用 WLS 進行異方差的消除(W=1/RESID)
Dependent Variable: Y Method: Least Squares Date: 06/23/10
Time: 19:59 Sample: 1 27 Included observations: 27 Weighting series: RESID Variable Coefficient Std. Error t-Statistic Prob.
C 58.98937 22.78914 2.588486 0.0158
X 0.067308 0.018290 3.680133 0.0011 Weighted Statistics
R-squared 0.941484
Mean dependent var -1.18E+17 Adjusted R-squared 0.939144
S.D. dependent var 8.31E+17 S.E. of regression 2.05E+17
Akaike info criterion 82.63371 Sum squared resid 1.05E+36
Schwarz criterion 82.72969 Log likelihood -1113.555
F-statistic 13.54338 Durbin-Watson stat 0.338876
Prob(F-statistic) 0.001121 Unweighted Statistics
R-squared 0.557188
Mean dependent var 94.44444 Adjusted R-squared 0.539475
S.D. dependent var 45.00712 S.E. of regression 30.54273
Sum squared resid 23321.45 Durbin-Watson stat 1.287687
二、
對區(qū) 某地區(qū) 1 31 年來居民的收入與儲蓄建立的線性回歸模型進行異方差檢驗及校正方法。
Dependent Variable: Y Method: Least Squares Date: 06/23/10
Time: 20:08 Sample: 1 31 Included observations: 31 Variable Coefficient Std. Error t-Statistic Prob.
C -665.6043 113.4187 -5.868556 0.0000 X 0.084550 0.004687 18.04056 0.0000 R-squared 0.918186
Mean dependent var 1230.000 Adjusted R-squared 0.915365
S.D. dependent var 817.1759 S.E. of regression 237.7341
Akaike info criterion 13.84252 Sum squared resid 1639007.
Schwarz criterion 13.93504 Log likelihood -212.5591
F-statistic 325.4618 Durbin-Watson stat 1.036781
Prob(F-statistic) 0.000000 Y=-665.6+0.08X R^2=0.918
(-5.87)
(18.04) Goldfeld-Quandt 檢驗前 10 個數(shù)據(jù)的回歸 Dependent Variable: Y Method: Least Squares Date: 06/23/10
Time: 21:19 Sample: 1 11 Included observations: 11
Variable Coefficient Std. Error t-Statistic Prob.
C -744.6351 195.4108 -3.810614 0.0041 X 0.088258 0.015705 5.619619 0.0003 R-squared 0.778216
Mean dependent var 331.3636 Adjusted R-squared 0.753574
S.D. dependent var 260.8157 S.E. of regression 129.4724
Akaike info criterion 12.72778 Sum squared resid 150867.9
Schwarz criterion 12.80012 Log likelihood -68.00278
F-statistic 31.58011 Durbin-Watson stat 1.142088
Prob(F-statistic) 0.000326 RSS1= 150867.9
后 后 10 個數(shù)據(jù)的回歸 Dependent Variable: Y Method: Least Squares Date: 06/23/10
Time: 21:21 Sample: 20 31 Included observations: 12 Variable Coefficient Std. Error t-Statistic Prob.
C 1141.066 709.8428 1.607491 0.1390 X 0.029409 0.021992 1.337264 0.2108 R-squared 0.151699
Mean dependent var 2084.250 Adjusted R-squared 0.066869
S.D. dependent var 287.2405 S.E. of regression 277.4706
Akaike info criterion 14.24032 Sum squared resid 769899.2
Schwarz criterion 14.32114 Log likelihood -83.44191
F-statistic 1.788274 Durbin-Watson stat 2.864726
Prob(F-statistic) 0.210758
RSS2= 769899.2
F=FRSS2/RSS1=5.103>F(8,8)=3.44 所以存在異方差 用 利用 WLS 進行消除(W=1/RESID) Dependent Variable: Y Method: Least Squares Date: 06/23/10
Time: 20:41 Sample: 1 31 Included observations: 31 Weighting series: 1/RESID Variable Coefficient Std. Error t-Statistic Prob.
C -686.0761 23.55233 -29.12986 0.0000
X 0.085747 0.001967 43.58293 0.0000 Weighted Statistics
R-squared 0.995497
Mean dependent var 126.3255 Adjusted R-squared 0.995342
S.D. dependent var 1586.032 S.E. of regression 108.2469
Akaike info criterion 12.26905 Sum squared resid 339804.5
Schwarz criterion 12.36156 Log likelihood -188.1702
F-statistic 1899.471 Durbin-Watson stat 0.156397
Prob(F-statistic) 0.000000 Unweighted Statistics
R-squared 0.917939
Mean dependent var 1230.000 Adjusted R-squared 0.915110
S.D. dependent var 817.1759 S.E. of regression 238.0918
Sum squared resid 1643943. Durbin-Watson stat 1.923620
、 三、 全國各地區(qū)年人均通訊 費用支出與家庭可支配收入建立的線性回歸模型進行異方差檢驗及校正方法。
Goldfeld-Quandt 檢驗前 10 個數(shù)據(jù)的回歸 Dependent Variable: Y Method: Least Squares Date: 06/23/10
Time: 21:09 Sample: 1 30 Included observations: 30 Variable Coefficient Std. Error t-Statistic Prob.
C -56.91798 36.20624 -1.572049 0.1272 X 0.058075 0.006480 8.962009 0.0000 R-squared 0.741501
Mean dependent var 256.8727 Adjusted R-squared 0.732269
S.D. dependent var 97.56583 S.E. of regression 50.48324
Akaike info criterion 10.74550 Sum squared resid 71359.62
Schwarz criterion 10.83891 Log likelihood -159.1825
F-statistic 80.31760 Durbin-Watson stat 2.008179
Prob(F-statistic) 0.000000 Goldfeld-Quandt 檢驗前 10 個數(shù)據(jù)的回歸 Dependent Variable: Y Method: Least Squares Date: 06/23/10
Time: 21:12 Sample: 1 10 Included observations: 10 Variable Coefficient Std. Error t-Statistic Prob.
C -261.1499 358.2945 -0.728869 0.4869 X 0.106334 0.085327 1.246183 0.2480
R-squared 0.162564
Mean dependent var 185.2400 Adjusted R-squared 0.057885
S.D. dependent var 25.97864 S.E. of regression 25.21555
Akaike info criterion 9.469655 Sum squared resid 5086.592
Schwarz criterion 9.530172 Log likelihood -45.34828
F-statistic 1.552972 Durbin-Watson stat 3.044685
Prob(F-statistic) 0.247952
RSS1=5086.592
后 后 10 個數(shù)據(jù)的回歸 Dependent Variable: Y Method: Least Squares Date: 06/23/10
Time: 21:13 Sample: 21 30 Included observations: 10 Variable Coefficient Std. Error t-Statistic Prob.
C -75.48340 154.9201 -0.487241 0.6392 X 0.060433 0.021628 2.794170 0.0234 R-squared 0.493907
Mean dependent var 350.4440 Adjusted R-squared 0.430646
S.D. dependent var 115.8410 S.E. of regression 87.40844
Akaike info criterion 11.95592 Sum squared resid 61121.88
Schwarz criterion 12.01643 Log likelihood -57.77959
F-statistic 7.807387 Durbin-Watson stat 1.846850
Prob(F-statistic) 0.023407 Rss2=61121.88 F=Rss2/Rss1=12.02>F(8,8)=3.44 所以存在異方差 用 利用 WLS 進行消除(W=1/RESID) Dependent Variable: Y Method: Least Squares Date: 06/23/10
Time: 21:16 Sample: 1 30 Included observations: 30 Weighting series: 1/RESID Variable Coefficient Std. Error t-Statistic Prob.
C -46.99125 9.238453 -5.086485 0.0000 X 0.056230 0.001717 32.74588 0.0000
Weighted Statistics
R-squared 1.000000
Mean dependent var 255.5239 Adjusted R-squared 1.000000
S.D. dependent var 1400.279 S.E. of regression 0.025604
Akaike info criterion -4.427763 Sum squared resid 0.018356
Schwarz criterion -4.334350 Log likelihood 68.41644
F-statistic 1072.292 Durbin-Watson stat 0.130304
Prob(F-statistic) 0.000000 Unweighted Statistics
R-squared 0.740752
Mean dependent var 256.8727 Adjusted R-squared 0.731494
S.D. dependent var 97.56583 S.E. of regression 50.55628
Sum squared resid 71566.25 Durbin-Watson stat 1.998810
實驗五
序列自相關(guān)模擬實驗
一、實驗?zāi)康模毫私庑蛄邢嚓P(guān)模型的檢驗方法以及序列相關(guān)模型的處理方法。
二、實驗要求:
(1)模擬線性回歸模型中隨機擾動項為序列自相關(guān)的樣本數(shù)據(jù), (2)進行 D-W 檢驗; (3)利用 Durbin 兩步法進行參數(shù)估計,建立模型 三 、實驗結(jié)果報告:
。▏@實驗要求,結(jié)合實驗的內(nèi)容撰寫報告)
實驗六
計量經(jīng)濟分析的創(chuàng)新性實驗
一、實驗?zāi)康模禾岣哂嬃糠治龅膭?chuàng)新能力。
二、實驗要求 求:
(1)提出一個經(jīng)濟問題; (2)提出經(jīng)濟模型;
(3)收集相關(guān)數(shù)據(jù)并進行檢驗; (4)建立計量經(jīng)濟模型,并提出對策建議。
三 、實驗結(jié)果報告:
。▏@實驗要求,結(jié)合實驗的內(nèi)容撰寫報告)
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