#datos

library(readxl)
coste_de_mantenimiento_xlsx <- read_excel("C:/Users/mende/OneDrive/Escritorio/Econometria/practicas/coste de mantenimiento.xlsx.xlsx")
head(coste_de_mantenimiento_xlsx,n = 8)
## # A tibble: 8 × 3
##       Y    X1    X2
##   <dbl> <dbl> <dbl>
## 1   320    50   7.4
## 2   450    53   5.1
## 3   370    60   4.2
## 4   470    63   3.9
## 5   420    69   1.4
## 6   500    82   2.2
## 7   570   100   7  
## 8   640   104   5.7

Regresion lineal

library(stargazer)
modelo_reglin<-lm(formula = Y~X1+X2+(X1*X2),data = coste_de_mantenimiento_xlsx)

#summary
summary(modelo_reglin)
## 
## Call:
## lm(formula = Y ~ X1 + X2 + (X1 * X2), data = coste_de_mantenimiento_xlsx)
## 
## Residuals:
##      Min       1Q   Median       3Q      Max 
## -108.527  -37.595   -2.745   52.292  102.808 
## 
## Coefficients:
##              Estimate Std. Error t value Pr(>|t|)    
## (Intercept) 303.50401   71.54695   4.242 0.000621 ***
## X1            2.32927    0.47698   4.883 0.000166 ***
## X2          -25.07113   11.48487  -2.183 0.044283 *  
## X1:X2         0.28617    0.07681   3.726 0.001840 ** 
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 67.68 on 16 degrees of freedom
## Multiple R-squared:  0.9634, Adjusted R-squared:  0.9566 
## F-statistic: 140.4 on 3 and 16 DF,  p-value: 1.054e-11
#stargazer
stargazer(modelo_reglin,title = "regrecion de coste",type = "text",digits = 6)
## 
## regrecion de coste
## ===============================================
##                         Dependent variable:    
##                     ---------------------------
##                                  Y             
## -----------------------------------------------
## X1                          2.329275***        
##                             (0.476982)         
##                                                
## X2                         -25.071130**        
##                             (11.484870)        
##                                                
## X1:X2                       0.286169***        
##                             (0.076813)         
##                                                
## Constant                   303.504000***       
##                             (71.546950)        
##                                                
## -----------------------------------------------
## Observations                    20             
## R2                           0.963414          
## Adjusted R2                  0.956554          
## Residual Std. Error     67.677750 (df = 16)    
## F Statistic         140.440600*** (df = 3; 16) 
## ===============================================
## Note:               *p<0.1; **p<0.05; ***p<0.01

Vector de Coeficientes estimados βˆ

options(scipen = 9999)
modelo_reglin$coefficients
## (Intercept)          X1          X2       X1:X2 
## 303.5040143   2.3292746 -25.0711288   0.2861686

Matriz de Varianza - Covarianza de los parametros V[β]

var_covar<-vcov(modelo_reglin)
print(var_covar)
##             (Intercept)           X1           X2        X1:X2
## (Intercept)  5118.96645 -31.10997447 -722.8989902  4.493190281
## X1            -31.10997   0.22751204    4.5755139 -0.033223456
## X2           -722.89899   4.57551391  131.9021598 -0.822206343
## X1:X2           4.49319  -0.03322346   -0.8222063  0.005900226

Intervalos de confianza

confint(object = modelo_reglin,level = .90)
##                     5 %       95 %
## (Intercept) 178.5913573 428.416671
## X1            1.4965192   3.162030
## X2          -45.1223698  -5.019888
## X1:X2         0.1520621   0.420275

Valores Ajustados Yˆ

plot(modelo_reglin$fitted.values,main ="valores ajustados",ylab = "Y",xlab = "casos")

modelo_reglin$fitted.values
##         1         2         3         4         5         6         7         8 
##  340.3238  376.4442  410.0762  422.7825  456.7683  490.9729  561.2516  572.4839 
##         9        10        11        12        13        14        15        16 
##  661.8956  805.2546  743.9514  802.6063  921.3246 1038.5268  966.3846  967.1923 
##        17        18        19        20 
## 1087.4101 1280.2249 1349.9604 1214.1649

Residuos del Modelo ϵˆ

plot(modelo_reglin$residuals,main = "Residuos", ylab = "Residuos",xlab = "casos")

modelo_reglin$residuals
##           1           2           3           4           5           6 
##  -20.323767   73.555820  -40.076233   47.217467  -36.768268    9.027138 
##           7           8           9          10          11          12 
##    8.748419   67.516125    8.104393  -25.254613  -53.951414 -102.606335 
##          13          14          15          16          17          18 
##  -11.324647 -108.526815  -26.384626  102.807683   72.589856  -70.224936 
##          19          20 
##  100.039646    5.835106

matrices A & P & M

matriz_x<-model.matrix(modelo_reglin)
#Matriz X'x
matriz_xx<-t(matriz_x)%*%matriz_x
print(matriz_xx)
##             (Intercept)        X1        X2      X1:X2
## (Intercept)        20.0    3036.0    121.20    18754.2
## X1               3036.0  574618.0  18754.20  3537032.8
## X2                121.2   18754.2    999.94   152648.7
## X1:X2           18754.2 3537032.8 152648.68 27682881.9
#Matriz A
solve(matriz_xx)%*%t(matriz_x)->matriz_A
print(matriz_A)
##                         1              2            3             4
## (Intercept) -0.0269643876  0.21786063243  0.294409235  0.3152011324
## X1           0.0003999215 -0.00102548702 -0.001444105 -0.0015490795
## X2           0.0388047049 -0.00653630884 -0.022176619 -0.0266881805
## X1:X2       -0.0002334413  0.00002923967  0.000116450  0.0001404267
##                         5             6              7              8
## (Intercept)  0.5227546767  0.3904003745  0.02028463523  0.09313147605
## X1          -0.0026669364 -0.0018298820  0.00009025813 -0.00023211650
## X2          -0.0659240840 -0.0449422757  0.01799521280  0.00379733432
## X1:X2        0.0003536128  0.0002236575 -0.00009921704 -0.00003296119
##                         9            10            11            12
## (Intercept) -0.2653043830 -0.2622967332  0.0443152123 -0.0545535472
## X1           0.0011696748  0.0005835039  0.0002043562  0.0012880664
## X2           0.0665768143  0.0616052800  0.0015591322  0.0122720018
## X1:X2       -0.0002833581 -0.0001595452 -0.0000370955 -0.0001763267
##                       13             14            15            16
## (Intercept) -0.072917817 -0.01500641231 -0.2239786763 -0.3262481783
## X1           0.001143413  0.00042125956  0.0024639940  0.0033485820
## X2           0.010376875 -0.00402060621  0.0315412720  0.0476387398
## X1:X2       -0.000121078  0.00002711295 -0.0003105392 -0.0004487073
##                        17            18            19            20
## (Intercept) -0.1381839072  0.1833273040  0.2993764155  0.0043929480
## X1           0.0015362166 -0.0014987044 -0.0025763624  0.0001734280
## X2           0.0122853632 -0.0478476959 -0.0696793809 -0.0166375793
## X1:X2       -0.0001273987  0.0004096502  0.0006014359  0.0001280827
#matriz P
matriz_x%*%matriz_A->matriz_P
print(matriz_P)
##              1            2             3            4            5
## 1   0.19381324  0.129036273  0.1011834639  0.092212497  0.032406355
## 2   0.12903627  0.138078127  0.1362473103  0.134947532  0.140775748
## 3   0.10118346  0.136247310  0.1439664947  0.145553529  0.174967755
## 4   0.09221250  0.134947532  0.1455535292  0.148028057  0.184516411
## 5   0.03240635  0.140775748  0.1749677551  0.184516411  0.280601341
## 6   0.04908672  0.124665653  0.1482115949  0.154795589  0.222824650
## 7   0.12125181  0.090025536  0.0762773231  0.071774601  0.042121378
## 8   0.09743028  0.091286297  0.0868470703  0.085219176  0.079247655
## 9   0.18100528  0.059638434  0.0130924780 -0.001586386 -0.118761676
## 10  0.16372580  0.039690827 -0.0087497204 -0.024475658 -0.151199641
## 11  0.05234526  0.053070750  0.0537768719  0.054155902  0.057015148
## 12  0.03542173  0.028640088  0.0298385285  0.031131985  0.034470683
## 13  0.01624282  0.007877722  0.0087581517  0.009838119  0.008809143
## 14 -0.01366413 -0.005856117  0.0002150787  0.002514228  0.011050760
## 15  0.01772693 -0.016465255 -0.0219215745 -0.022035577 -0.039803397
## 16  0.02768589 -0.027101345 -0.0383247931 -0.039743813 -0.071846910
## 17 -0.01759892 -0.028544954 -0.0265168679 -0.024791215 -0.027292170
## 18 -0.09411030 -0.029398837 -0.0043234403  0.002953959  0.052502132
## 19 -0.12253784 -0.029967514  0.0037031147  0.013088796  0.082154982
## 20 -0.06266315 -0.036646273 -0.0228023690 -0.018097732  0.005439657
##               6           7            8            9           10         11
## 1   0.049086720  0.12125181  0.097430285  0.181005277  0.163725800 0.05234526
## 2   0.124665653  0.09002554  0.091286297  0.059638434  0.039690827 0.05307075
## 3   0.148211595  0.07627732  0.086847070  0.013092478 -0.008749720 0.05377687
## 4   0.154795589  0.07177460  0.085219176 -0.001586386 -0.024475658 0.05415590
## 5   0.222824650  0.04212138  0.079247655 -0.118761676 -0.151199641 0.05701515
## 6   0.181824864  0.04937652  0.076505860 -0.074039863 -0.107699756 0.05781048
## 7   0.049376516  0.08582501  0.073428333  0.119350110  0.115608957 0.04969791
## 8   0.076505860  0.07342833  0.071096772  0.067854942  0.054959357 0.05246510
## 9  -0.074039863  0.11935011  0.067854942  0.319570105  0.374493574 0.03291963
## 10 -0.107699756  0.11560896  0.054959357  0.374493574  0.483734939 0.01736368
## 11  0.057810481  0.04969791  0.052465096  0.032919625  0.017363681 0.05454216
## 12  0.046256974  0.03672845  0.044829330 -0.009255161 -0.061772505 0.06635373
## 13  0.021828668  0.02930695  0.033370226  0.012993057 -0.012231797 0.05889144
## 14  0.015582714  0.01795437  0.021959684  0.020061277  0.031624199 0.04841884
## 15 -0.008561643  0.02583218  0.027974307  0.007952119 -0.048452187 0.06891842
## 16 -0.027806025  0.02798608  0.027551473  0.011987645 -0.066301176 0.07573560
## 17 -0.008169078  0.01225618  0.016087216  0.007758466 -0.008609916 0.05744390
## 18  0.029069502 -0.01472189 -0.002429200 -0.006425960  0.077167686 0.02788077
## 19  0.043319093 -0.02501037 -0.009206552 -0.014246880  0.103968771 0.01765567
## 20  0.005117486 -0.00506943  0.003522672 -0.004361183  0.027154564 0.04353875
##              12           13            14           15          16
## 1   0.035421725  0.016242817 -0.0136641286  0.017726930  0.02768589
## 2   0.028640088  0.007877722 -0.0058561168 -0.016465255 -0.02710135
## 3   0.029838529  0.008758152  0.0002150787 -0.021921574 -0.03832479
## 4   0.031131985  0.009838119  0.0025142276 -0.022035577 -0.03974381
## 5   0.034470683  0.008809143  0.0110507595 -0.039803397 -0.07184691
## 6   0.046256974  0.021828668  0.0155827141 -0.008561643 -0.02780602
## 7   0.036728450  0.029306947  0.0179543655  0.025832182  0.02798608
## 8   0.044829330  0.033370226  0.0219596835  0.027974307  0.02755147
## 9  -0.009255161  0.012993057  0.0200612774  0.007952119  0.01198764
## 10 -0.061772505 -0.012231797  0.0316241994 -0.048452187 -0.06630118
## 11  0.066353735  0.058891445  0.0484188370  0.068918416  0.07573560
## 12  0.121621418  0.100578949  0.0638133975  0.150471895  0.18247104
## 13  0.100578949  0.094687541  0.0766409627  0.133403695  0.15666477
## 14  0.063813397  0.076640963  0.0879569172  0.088464457  0.09206349
## 15  0.150471895  0.133403695  0.0884644569  0.213644887  0.26420835
## 16  0.182471043  0.156664770  0.0920634863  0.264208351  0.33328907
## 17  0.108627255  0.111610526  0.0999420803  0.159565062  0.18661128
## 18 -0.011671138  0.037646387  0.1125960736 -0.012796988 -0.05523773
## 19 -0.053321689  0.012099216  0.1174654547 -0.072852378 -0.13975401
## 20  0.054765037  0.080983456  0.1111962734  0.084726697  0.07986110
##              17           18           19           20
## 1  -0.017598924 -0.094110303 -0.122537845 -0.062663147
## 2  -0.028544954 -0.029398837 -0.029967514 -0.036646273
## 3  -0.026516868 -0.004323440  0.003703115 -0.022802369
## 4  -0.024791215  0.002953959  0.013088796 -0.018097732
## 5  -0.027292170  0.052502132  0.082154982  0.005439657
## 6  -0.008169078  0.029069502  0.043319093  0.005117486
## 7   0.012256176 -0.014721888 -0.025010370 -0.005069430
## 8   0.016087216 -0.002429200 -0.009206552  0.003522672
## 9   0.007758466 -0.006425960 -0.014246880 -0.004361183
## 10 -0.008609916  0.077167686  0.103968771  0.027154564
## 11  0.057443899  0.027880775  0.017655665  0.043538746
## 12  0.108627255 -0.011671138 -0.053321689  0.054765037
## 13  0.111610526  0.037646387  0.012099216  0.080983456
## 14  0.099942080  0.112596074  0.117465455  0.111196273
## 15  0.159565062 -0.012796988 -0.072852378  0.084726697
## 16  0.186611278 -0.055237727 -0.139754007  0.079861104
## 17  0.143621327  0.072458882  0.048021095  0.117519864
## 18  0.072458882  0.282503205  0.357117396  0.179219484
## 19  0.048021095  0.357117396  0.466651545  0.201652106
## 20  0.117519864  0.179219484  0.201652106  0.154942988
#Matriz M
diag(20)-matriz_P->matriz_M
print(matriz_M)
##              1            2             3            4            5
## 1   0.80618676 -0.129036273 -0.1011834639 -0.092212497 -0.032406355
## 2  -0.12903627  0.861921873 -0.1362473103 -0.134947532 -0.140775748
## 3  -0.10118346 -0.136247310  0.8560335053 -0.145553529 -0.174967755
## 4  -0.09221250 -0.134947532 -0.1455535292  0.851971943 -0.184516411
## 5  -0.03240635 -0.140775748 -0.1749677551 -0.184516411  0.719398659
## 6  -0.04908672 -0.124665653 -0.1482115949 -0.154795589 -0.222824650
## 7  -0.12125181 -0.090025536 -0.0762773231 -0.071774601 -0.042121378
## 8  -0.09743028 -0.091286297 -0.0868470703 -0.085219176 -0.079247655
## 9  -0.18100528 -0.059638434 -0.0130924780  0.001586386  0.118761676
## 10 -0.16372580 -0.039690827  0.0087497204  0.024475658  0.151199641
## 11 -0.05234526 -0.053070750 -0.0537768719 -0.054155902 -0.057015148
## 12 -0.03542173 -0.028640088 -0.0298385285 -0.031131985 -0.034470683
## 13 -0.01624282 -0.007877722 -0.0087581517 -0.009838119 -0.008809143
## 14  0.01366413  0.005856117 -0.0002150787 -0.002514228 -0.011050760
## 15 -0.01772693  0.016465255  0.0219215745  0.022035577  0.039803397
## 16 -0.02768589  0.027101345  0.0383247931  0.039743813  0.071846910
## 17  0.01759892  0.028544954  0.0265168679  0.024791215  0.027292170
## 18  0.09411030  0.029398837  0.0043234403 -0.002953959 -0.052502132
## 19  0.12253784  0.029967514 -0.0037031147 -0.013088796 -0.082154982
## 20  0.06266315  0.036646273  0.0228023690  0.018097732 -0.005439657
##               6           7            8            9           10          11
## 1  -0.049086720 -0.12125181 -0.097430285 -0.181005277 -0.163725800 -0.05234526
## 2  -0.124665653 -0.09002554 -0.091286297 -0.059638434 -0.039690827 -0.05307075
## 3  -0.148211595 -0.07627732 -0.086847070 -0.013092478  0.008749720 -0.05377687
## 4  -0.154795589 -0.07177460 -0.085219176  0.001586386  0.024475658 -0.05415590
## 5  -0.222824650 -0.04212138 -0.079247655  0.118761676  0.151199641 -0.05701515
## 6   0.818175136 -0.04937652 -0.076505860  0.074039863  0.107699756 -0.05781048
## 7  -0.049376516  0.91417499 -0.073428333 -0.119350110 -0.115608957 -0.04969791
## 8  -0.076505860 -0.07342833  0.928903228 -0.067854942 -0.054959357 -0.05246510
## 9   0.074039863 -0.11935011 -0.067854942  0.680429895 -0.374493574 -0.03291963
## 10  0.107699756 -0.11560896 -0.054959357 -0.374493574  0.516265061 -0.01736368
## 11 -0.057810481 -0.04969791 -0.052465096 -0.032919625 -0.017363681  0.94545784
## 12 -0.046256974 -0.03672845 -0.044829330  0.009255161  0.061772505 -0.06635373
## 13 -0.021828668 -0.02930695 -0.033370226 -0.012993057  0.012231797 -0.05889144
## 14 -0.015582714 -0.01795437 -0.021959684 -0.020061277 -0.031624199 -0.04841884
## 15  0.008561643 -0.02583218 -0.027974307 -0.007952119  0.048452187 -0.06891842
## 16  0.027806025 -0.02798608 -0.027551473 -0.011987645  0.066301176 -0.07573560
## 17  0.008169078 -0.01225618 -0.016087216 -0.007758466  0.008609916 -0.05744390
## 18 -0.029069502  0.01472189  0.002429200  0.006425960 -0.077167686 -0.02788077
## 19 -0.043319093  0.02501037  0.009206552  0.014246880 -0.103968771 -0.01765567
## 20 -0.005117486  0.00506943 -0.003522672  0.004361183 -0.027154564 -0.04353875
##              12           13            14           15          16
## 1  -0.035421725 -0.016242817  0.0136641286 -0.017726930 -0.02768589
## 2  -0.028640088 -0.007877722  0.0058561168  0.016465255  0.02710135
## 3  -0.029838529 -0.008758152 -0.0002150787  0.021921574  0.03832479
## 4  -0.031131985 -0.009838119 -0.0025142276  0.022035577  0.03974381
## 5  -0.034470683 -0.008809143 -0.0110507595  0.039803397  0.07184691
## 6  -0.046256974 -0.021828668 -0.0155827141  0.008561643  0.02780602
## 7  -0.036728450 -0.029306947 -0.0179543655 -0.025832182 -0.02798608
## 8  -0.044829330 -0.033370226 -0.0219596835 -0.027974307 -0.02755147
## 9   0.009255161 -0.012993057 -0.0200612774 -0.007952119 -0.01198764
## 10  0.061772505  0.012231797 -0.0316241994  0.048452187  0.06630118
## 11 -0.066353735 -0.058891445 -0.0484188370 -0.068918416 -0.07573560
## 12  0.878378582 -0.100578949 -0.0638133975 -0.150471895 -0.18247104
## 13 -0.100578949  0.905312459 -0.0766409627 -0.133403695 -0.15666477
## 14 -0.063813397 -0.076640963  0.9120430828 -0.088464457 -0.09206349
## 15 -0.150471895 -0.133403695 -0.0884644569  0.786355113 -0.26420835
## 16 -0.182471043 -0.156664770 -0.0920634863 -0.264208351  0.66671093
## 17 -0.108627255 -0.111610526 -0.0999420803 -0.159565062 -0.18661128
## 18  0.011671138 -0.037646387 -0.1125960736  0.012796988  0.05523773
## 19  0.053321689 -0.012099216 -0.1174654547  0.072852378  0.13975401
## 20 -0.054765037 -0.080983456 -0.1111962734 -0.084726697 -0.07986110
##              17           18           19           20
## 1   0.017598924  0.094110303  0.122537845  0.062663147
## 2   0.028544954  0.029398837  0.029967514  0.036646273
## 3   0.026516868  0.004323440 -0.003703115  0.022802369
## 4   0.024791215 -0.002953959 -0.013088796  0.018097732
## 5   0.027292170 -0.052502132 -0.082154982 -0.005439657
## 6   0.008169078 -0.029069502 -0.043319093 -0.005117486
## 7  -0.012256176  0.014721888  0.025010370  0.005069430
## 8  -0.016087216  0.002429200  0.009206552 -0.003522672
## 9  -0.007758466  0.006425960  0.014246880  0.004361183
## 10  0.008609916 -0.077167686 -0.103968771 -0.027154564
## 11 -0.057443899 -0.027880775 -0.017655665 -0.043538746
## 12 -0.108627255  0.011671138  0.053321689 -0.054765037
## 13 -0.111610526 -0.037646387 -0.012099216 -0.080983456
## 14 -0.099942080 -0.112596074 -0.117465455 -0.111196273
## 15 -0.159565062  0.012796988  0.072852378 -0.084726697
## 16 -0.186611278  0.055237727  0.139754007 -0.079861104
## 17  0.856378673 -0.072458882 -0.048021095 -0.117519864
## 18 -0.072458882  0.717496795 -0.357117396 -0.179219484
## 19 -0.048021095 -0.357117396  0.533348455 -0.201652106
## 20 -0.117519864 -0.179219484 -0.201652106  0.845057012
#Matriz y
library(dplyr)
coste_de_mantenimiento_xlsx$Y %>% as.matrix(modelo_reglin)->matriz_Y
print(matriz_Y)
##       [,1]
##  [1,]  320
##  [2,]  450
##  [3,]  370
##  [4,]  470
##  [5,]  420
##  [6,]  500
##  [7,]  570
##  [8,]  640
##  [9,]  670
## [10,]  780
## [11,]  690
## [12,]  700
## [13,]  910
## [14,]  930
## [15,]  940
## [16,] 1070
## [17,] 1160
## [18,] 1210
## [19,] 1450
## [20,] 1220
#Vector de Coeficientes estimados βˆ
matriz_A%*%matriz_Y
##                    [,1]
## (Intercept) 303.5040143
## X1            2.3292746
## X2          -25.0711288
## X1:X2         0.2861686
#Valores Ajustados Yˆ
t(matriz_P%*%matriz_Y)
##             1        2        3        4        5        6        7        8
## [1,] 340.3238 376.4442 410.0762 422.7825 456.7683 490.9729 561.2516 572.4839
##             9       10       11       12       13       14       15       16
## [1,] 661.8956 805.2546 743.9514 802.6063 921.3246 1038.527 966.3846 967.1923
##           17       18      19       20
## [1,] 1087.41 1280.225 1349.96 1214.165
#Residuos del Modelo ϵˆ
t(matriz_M%*%matriz_Y)
##              1        2         3        4         5        6        7        8
## [1,] -20.32377 73.55582 -40.07623 47.21747 -36.76827 9.027138 8.748419 67.51613
##             9        10        11        12        13        14        15
## [1,] 8.104393 -25.25461 -53.95141 -102.6063 -11.32465 -108.5268 -26.38463
##            16       17        18       19       20
## [1,] 102.8077 72.58986 -70.22494 100.0396 5.835106