#DATOS DEL MODELO

library(wooldridge)
data(hpricel)
## Warning in data(hpricel): data set 'hpricel' not found
head(force(hprice1),n=5)
##   price assess bdrms lotsize sqrft colonial   lprice  lassess llotsize   lsqrft
## 1   300  349.1     4    6126  2438        1 5.703783 5.855359 8.720297 7.798934
## 2   370  351.5     3    9903  2076        1 5.913503 5.862210 9.200593 7.638198
## 3   191  217.7     3    5200  1374        0 5.252274 5.383118 8.556414 7.225482
## 4   195  231.8     3    4600  1448        1 5.273000 5.445875 8.433811 7.277938
## 5   373  319.1     4    6095  2514        1 5.921578 5.765504 8.715224 7.829630
library(stargazer)
## 
## Please cite as:
##  Hlavac, Marek (2022). stargazer: Well-Formatted Regression and Summary Statistics Tables.
##  R package version 5.2.3. https://CRAN.R-project.org/package=stargazer
modelo_estimado<-lm(price~lotsize+sqrft+bdrms,data = hprice1)
options(scipen = 9999)
stargazer(modelo_estimado,type = "html",title = "modelo estimado")
## 
## <table style="text-align:center"><caption><strong>modelo estimado</strong></caption>
## <tr><td colspan="2" style="border-bottom: 1px solid black"></td></tr><tr><td style="text-align:left"></td><td><em>Dependent variable:</em></td></tr>
## <tr><td></td><td colspan="1" style="border-bottom: 1px solid black"></td></tr>
## <tr><td style="text-align:left"></td><td>price</td></tr>
## <tr><td colspan="2" style="border-bottom: 1px solid black"></td></tr><tr><td style="text-align:left">lotsize</td><td>0.002<sup>***</sup></td></tr>
## <tr><td style="text-align:left"></td><td>(0.001)</td></tr>
## <tr><td style="text-align:left"></td><td></td></tr>
## <tr><td style="text-align:left">sqrft</td><td>0.123<sup>***</sup></td></tr>
## <tr><td style="text-align:left"></td><td>(0.013)</td></tr>
## <tr><td style="text-align:left"></td><td></td></tr>
## <tr><td style="text-align:left">bdrms</td><td>13.853</td></tr>
## <tr><td style="text-align:left"></td><td>(9.010)</td></tr>
## <tr><td style="text-align:left"></td><td></td></tr>
## <tr><td style="text-align:left">Constant</td><td>-21.770</td></tr>
## <tr><td style="text-align:left"></td><td>(29.475)</td></tr>
## <tr><td style="text-align:left"></td><td></td></tr>
## <tr><td colspan="2" style="border-bottom: 1px solid black"></td></tr><tr><td style="text-align:left">Observations</td><td>88</td></tr>
## <tr><td style="text-align:left">R<sup>2</sup></td><td>0.672</td></tr>
## <tr><td style="text-align:left">Adjusted R<sup>2</sup></td><td>0.661</td></tr>
## <tr><td style="text-align:left">Residual Std. Error</td><td>59.833 (df = 84)</td></tr>
## <tr><td style="text-align:left">F Statistic</td><td>57.460<sup>***</sup> (df = 3; 84)</td></tr>
## <tr><td colspan="2" style="border-bottom: 1px solid black"></td></tr><tr><td style="text-align:left"><em>Note:</em></td><td style="text-align:right"><sup>*</sup>p<0.1; <sup>**</sup>p<0.05; <sup>***</sup>p<0.01</td></tr>
## </table>
print(modelo_estimado)
## 
## Call:
## lm(formula = price ~ lotsize + sqrft + bdrms, data = hprice1)
## 
## Coefficients:
## (Intercept)      lotsize        sqrft        bdrms  
##  -21.770308     0.002068     0.122778    13.852522

#EVIDENCIA DE LA INDEPENDENCIA DE LOS REGRESORES

##Se basa la matriz XtX

library(stargazer)
X_mat<-model.matrix(modelo_estimado)
stargazer(head(X_mat,n=6),type="html")
## 
## <table style="text-align:center"><tr><td colspan="5" style="border-bottom: 1px solid black"></td></tr><tr><td style="text-align:left"></td><td>(Intercept)</td><td>lotsize</td><td>sqrft</td><td>bdrms</td></tr>
## <tr><td colspan="5" style="border-bottom: 1px solid black"></td></tr><tr><td style="text-align:left">1</td><td>1</td><td>6,126</td><td>2,438</td><td>4</td></tr>
## <tr><td style="text-align:left">2</td><td>1</td><td>9,903</td><td>2,076</td><td>3</td></tr>
## <tr><td style="text-align:left">3</td><td>1</td><td>5,200</td><td>1,374</td><td>3</td></tr>
## <tr><td style="text-align:left">4</td><td>1</td><td>4,600</td><td>1,448</td><td>3</td></tr>
## <tr><td style="text-align:left">5</td><td>1</td><td>6,095</td><td>2,514</td><td>4</td></tr>
## <tr><td style="text-align:left">6</td><td>1</td><td>8,566</td><td>2,754</td><td>5</td></tr>
## <tr><td colspan="5" style="border-bottom: 1px solid black"></td></tr></table>
print(X_mat)
##    (Intercept) lotsize sqrft bdrms
## 1            1    6126  2438     4
## 2            1    9903  2076     3
## 3            1    5200  1374     3
## 4            1    4600  1448     3
## 5            1    6095  2514     4
## 6            1    8566  2754     5
## 7            1    9000  2067     3
## 8            1    6210  1731     3
## 9            1    6000  1767     3
## 10           1    2892  1890     3
## 11           1    6000  2336     4
## 12           1    7047  2634     5
## 13           1   12237  3375     3
## 14           1    6460  1899     3
## 15           1    6519  2312     3
## 16           1    3597  1760     4
## 17           1    5922  2000     4
## 18           1    7123  1774     3
## 19           1    5642  1376     3
## 20           1    8602  1835     4
## 21           1    5494  2048     3
## 22           1    7800  2124     3
## 23           1    6003  1768     3
## 24           1    5218  1732     4
## 25           1    9425  1440     3
## 26           1    6114  1932     3
## 27           1    6710  1932     3
## 28           1    8577  2106     3
## 29           1    8400  3529     7
## 30           1    9773  2051     4
## 31           1    4806  1573     4
## 32           1   15086  2829     4
## 33           1    5763  1630     3
## 34           1    6383  1840     4
## 35           1    9000  2066     4
## 36           1    3500  1702     4
## 37           1   10892  2750     4
## 38           1   15634  3880     5
## 39           1    6400  1854     4
## 40           1    8880  1421     2
## 41           1    6314  1662     3
## 42           1   28231  3331     5
## 43           1    7050  1656     4
## 44           1    5305  1171     3
## 45           1    6637  2293     5
## 46           1    7834  1764     3
## 47           1    1000  2768     3
## 48           1    8112  3733     4
## 49           1    5850  1536     3
## 50           1    6660  1638     4
## 51           1    6637  1972     3
## 52           1   15267  1478     2
## 53           1    5146  1408     3
## 54           1    6017  1812     3
## 55           1    8410  1722     3
## 56           1    5625  1780     4
## 57           1    5600  1674     4
## 58           1    6525  1850     4
## 59           1    6060  1925     3
## 60           1    5539  2343     4
## 61           1    7566  1567     3
## 62           1    5484  1664     4
## 63           1    5348  1386     6
## 64           1   15834  2617     5
## 65           1    8022  2321     4
## 66           1   11966  2638     4
## 67           1    8460  1915     4
## 68           1   15105  2589     4
## 69           1   10859  2709     4
## 70           1    6300  1587     3
## 71           1   11554  1694     3
## 72           1    6000  1536     3
## 73           1   31000  3662     5
## 74           1    4054  1736     3
## 75           1   20700  2205     2
## 76           1    5525  1502     3
## 77           1   92681  1696     4
## 78           1    8178  2186     3
## 79           1    5944  1928     4
## 80           1   18838  1294     3
## 81           1    4315  1535     4
## 82           1    5167  1980     3
## 83           1    7893  2090     4
## 84           1    6056  1837     3
## 85           1    5828  1715     3
## 86           1    6341  1574     3
## 87           1    6362  1185     2
## 88           1    4950  1774     4
## attr(,"assign")
## [1] 0 1 2 3
XX_matrix<-t(X_mat)%*%X_mat
stargazer(XX_matrix,type = "html")
## 
## <table style="text-align:center"><tr><td colspan="5" style="border-bottom: 1px solid black"></td></tr><tr><td style="text-align:left"></td><td>(Intercept)</td><td>lotsize</td><td>sqrft</td><td>bdrms</td></tr>
## <tr><td colspan="5" style="border-bottom: 1px solid black"></td></tr><tr><td style="text-align:left">(Intercept)</td><td>88</td><td>793,748</td><td>177,205</td><td>314</td></tr>
## <tr><td style="text-align:left">lotsize</td><td>793,748</td><td>16,165,159,010</td><td>1,692,290,257</td><td>2,933,767</td></tr>
## <tr><td style="text-align:left">sqrft</td><td>177,205</td><td>1,692,290,257</td><td>385,820,561</td><td>654,755</td></tr>
## <tr><td style="text-align:left">bdrms</td><td>314</td><td>2,933,767</td><td>654,755</td><td>1,182</td></tr>
## <tr><td colspan="5" style="border-bottom: 1px solid black"></td></tr></table>
print(XX_matrix)
##             (Intercept)     lotsize      sqrft   bdrms
## (Intercept)          88      793748     177205     314
## lotsize          793748 16165159010 1692290257 2933767
## sqrft            177205  1692290257  385820561  654755
## bdrms               314     2933767     654755    1182

##Cálculo de la matriz de normalización:

library(stargazer)
options(scipen = 999)
Sn<-solve(diag(sqrt(diag(XX_matrix))))
stargazer(Sn,type = "html")
## 
## <table style="text-align:center"><tr><td colspan="4" style="border-bottom: 1px solid black"></td></tr><tr><td style="text-align:left">0.107</td><td>0</td><td>0</td><td>0</td></tr>
## <tr><td style="text-align:left">0</td><td>0.00001</td><td>0</td><td>0</td></tr>
## <tr><td style="text-align:left">0</td><td>0</td><td>0.0001</td><td>0</td></tr>
## <tr><td style="text-align:left">0</td><td>0</td><td>0</td><td>0.029</td></tr>
## <tr><td colspan="4" style="border-bottom: 1px solid black"></td></tr></table>
print(Sn)
##           [,1]           [,2]          [,3]       [,4]
## [1,] 0.1066004 0.000000000000 0.00000000000 0.00000000
## [2,] 0.0000000 0.000007865204 0.00000000000 0.00000000
## [3,] 0.0000000 0.000000000000 0.00005091049 0.00000000
## [4,] 0.0000000 0.000000000000 0.00000000000 0.02908649

##XtX normalizada:

library(stargazer)
XX_norm<-(Sn%*%XX_matrix)%*%Sn
stargazer(XX_norm,type = "html",digits = 4)
## 
## <table style="text-align:center"><tr><td colspan="4" style="border-bottom: 1px solid black"></td></tr><tr><td style="text-align:left">1</td><td>0.6655</td><td>0.9617</td><td>0.9736</td></tr>
## <tr><td style="text-align:left">0.6655</td><td>1</td><td>0.6776</td><td>0.6712</td></tr>
## <tr><td style="text-align:left">0.9617</td><td>0.6776</td><td>1</td><td>0.9696</td></tr>
## <tr><td style="text-align:left">0.9736</td><td>0.6712</td><td>0.9696</td><td>1</td></tr>
## <tr><td colspan="4" style="border-bottom: 1px solid black"></td></tr></table>
print(XX_norm)
##           [,1]      [,2]      [,3]      [,4]
## [1,] 1.0000000 0.6655050 0.9617052 0.9735978
## [2,] 0.6655050 1.0000000 0.6776293 0.6711613
## [3,] 0.9617052 0.6776293 1.0000000 0.9695661
## [4,] 0.9735978 0.6711613 0.9695661 1.0000000

##Autovalores de XtX Normalizada:

library(stargazer)
#autovalores
lambdas<-eigen(XX_norm,symmetric = TRUE)
stargazer(lambdas$values,type = "html")
## 
## <table style="text-align:center"><tr><td colspan="4" style="border-bottom: 1px solid black"></td></tr><tr><td style="text-align:left">3.482</td><td>0.455</td><td>0.039</td><td>0.025</td></tr>
## <tr><td colspan="4" style="border-bottom: 1px solid black"></td></tr></table>
print(lambdas)
## eigen() decomposition
## $values
## [1] 3.48158596 0.45518380 0.03851083 0.02471941
## 
## $vectors
##            [,1]       [,2]        [,3]         [,4]
## [1,] -0.5218678 -0.2571123  0.62342077  0.522392359
## [2,] -0.4243486  0.9052959  0.01913842 -0.001191578
## [3,] -0.5227488 -0.2283722 -0.77038705  0.284751906
## [4,] -0.5237518 -0.2493568  0.13222728 -0.803754412

##Cálculo de κ(x)

K<-sqrt(max(lambdas$values)/min(lambdas$values))
print(K)
## [1] 11.86778

CONCLUSION: Como K(x) < 20 se considera que la multicolinealidad es leve y no se considera un problema

#Cálculo del Indice de Condición usando librería “mctest”

library(mctest)
X_mat<-model.matrix(modelo_estimado)
mctest(mod = modelo_estimado)
## 
## Call:
## omcdiag(mod = mod, Inter = TRUE, detr = detr, red = red, conf = conf, 
##     theil = theil, cn = cn)
## 
## 
## Overall Multicollinearity Diagnostics
## 
##                        MC Results detection
## Determinant |X'X|:         0.6918         0
## Farrar Chi-Square:        31.3812         1
## Red Indicator:             0.3341         0
## Sum of Lambda Inverse:     3.8525         0
## Theil's Method:           -0.7297         0
## Condition Number:         11.8678         0
## 
## 1 --> COLLINEARITY is detected by the test 
## 0 --> COLLINEARITY is not detected by the test

#Cálculo del Indice de Condición usando librería “olsrr”

library(olsrr)
## 
## Attaching package: 'olsrr'
## The following object is masked from 'package:wooldridge':
## 
##     cement
## The following object is masked from 'package:datasets':
## 
##     rivers
ols_eigen_cindex(model = modelo_estimado)
##   Eigenvalue Condition Index   intercept      lotsize       sqrft       bdrms
## 1 3.48158596        1.000000 0.003663034 0.0277802824 0.004156293 0.002939554
## 2 0.45518380        2.765637 0.006800735 0.9670803174 0.006067321 0.005096396
## 3 0.03851083        9.508174 0.472581427 0.0051085488 0.816079307 0.016938178
## 4 0.02471941       11.867781 0.516954804 0.0000308514 0.173697079 0.975025872

#Prueba de Farrar-Glaubar

##Calculo de |R|

library(stargazer)
Zn<-scale(X_mat[,-1])
stargazer(head(Zn,n=6),type = "html")
## 
## <table style="text-align:center"><tr><td colspan="4" style="border-bottom: 1px solid black"></td></tr><tr><td style="text-align:left"></td><td>lotsize</td><td>sqrft</td><td>bdrms</td></tr>
## <tr><td colspan="4" style="border-bottom: 1px solid black"></td></tr><tr><td style="text-align:left">1</td><td>-0.284</td><td>0.735</td><td>0.513</td></tr>
## <tr><td style="text-align:left">2</td><td>0.087</td><td>0.108</td><td>-0.675</td></tr>
## <tr><td style="text-align:left">3</td><td>-0.375</td><td>-1.108</td><td>-0.675</td></tr>
## <tr><td style="text-align:left">4</td><td>-0.434</td><td>-0.980</td><td>-0.675</td></tr>
## <tr><td style="text-align:left">5</td><td>-0.287</td><td>0.867</td><td>0.513</td></tr>
## <tr><td style="text-align:left">6</td><td>-0.045</td><td>1.283</td><td>1.702</td></tr>
## <tr><td colspan="4" style="border-bottom: 1px solid black"></td></tr></table>
print(Zn)
##         lotsize       sqrft      bdrms
## 1  -0.284432952  0.73512302  0.5132184
## 2   0.086801976  0.10794824 -0.6752874
## 3  -0.375447923 -1.10828571 -0.6752874
## 4  -0.434420906 -0.98007871 -0.6752874
## 5  -0.287479889  0.86679507  0.5132184
## 6  -0.044609488  1.28260155  1.7017243
## 7  -0.001952363  0.09235550 -0.6752874
## 8  -0.276176734 -0.48977357 -0.6752874
## 9  -0.296817278 -0.42740260 -0.6752874
## 10 -0.602297331 -0.21430178 -0.6752874
## 11 -0.296817278  0.55840526  0.5132184
## 12 -0.193909423  1.07469831  1.7017243
## 13  0.316206880  2.35850081 -0.6752874
## 14 -0.251604658 -0.19870903 -0.6752874
## 15 -0.245805648  0.51682462 -0.6752874
## 16 -0.533004076 -0.43953029  0.5132184
## 17 -0.304483766 -0.02372381  0.5132184
## 18 -0.186439512 -0.41527491 -0.6752874
## 19 -0.332004492 -1.10482065 -0.6752874
## 20 -0.041071109 -0.30959076  0.5132184
## 21 -0.346551161  0.05943749 -0.6752874
## 22 -0.119898329  0.19110954 -0.6752874
## 23 -0.296522414 -0.42567007 -0.6752874
## 24 -0.373678733 -0.48804104  0.5132184
## 25  0.039820167 -0.99393893 -0.6752874
## 26 -0.285612412 -0.14153564 -0.6752874
## 27 -0.227032582 -0.14153564 -0.6752874
## 28 -0.043528316  0.15992405 -0.6752874
## 29 -0.060925346  2.62530997  4.0787359
## 30  0.074024497  0.06463507  0.5132184
## 31 -0.414173515 -0.76351284  0.5132184
## 32  0.596230262  1.41254107  0.5132184
## 33 -0.320111607 -0.66475880 -0.6752874
## 34 -0.259172858 -0.30092813  0.5132184
## 35 -0.001952363  0.09062297  0.5132184
## 36 -0.542538041 -0.54001685  0.5132184
## 37  0.184009110  1.27567144  0.5132184
## 38  0.650092253  3.23342695  1.7017243
## 39 -0.257501956 -0.27667275  0.5132184
## 40 -0.013746960 -1.02685694 -1.8637932
## 41 -0.265954751 -0.60931793 -0.6752874
## 42  1.888230032  2.28226963  1.7017243
## 43 -0.193614558 -0.61971309  0.5132184
## 44 -0.365127650 -1.45998869 -0.6752874
## 45 -0.234207628  0.48390660  1.7017243
## 46 -0.116556527 -0.43260018 -0.6752874
## 47 -0.788258804  1.30685693 -0.6752874
## 48 -0.089232378  2.97874548  0.5132184
## 49 -0.311560524 -0.82761633 -0.6752874
## 50 -0.231946997 -0.65089858  0.5132184
## 51 -0.234207628 -0.07223456 -0.6752874
## 52  0.614020445 -0.92810290 -1.8637932
## 53 -0.380755491 -1.04937979 -0.6752874
## 54 -0.295146377 -0.34943888 -0.6752874
## 55 -0.059942463 -0.50536631 -0.6752874
## 56 -0.333675393 -0.40487975  0.5132184
## 57 -0.336132600 -0.58852761  0.5132184
## 58 -0.245215918 -0.28360286  0.5132184
## 59 -0.290919980 -0.15366333 -0.6752874
## 60 -0.342128187  0.57053295  0.5132184
## 61 -0.142897793 -0.77390800 -0.6752874
## 62 -0.347534044 -0.60585288  0.5132184
## 63 -0.360901253 -1.08749538  2.8902301
## 64  0.669749914  1.04524535  1.7017243
## 65 -0.098078326  0.53241736  0.5132184
## 66  0.289570750  1.08162842  0.5132184
## 67 -0.055028048 -0.17098860  0.5132184
## 68  0.598097739  0.99673459  0.5132184
## 69  0.180765596  1.20463783  0.5132184
## 70 -0.267330787 -0.73925746 -0.6752874
## 71  0.249075968 -0.55387707 -0.6752874
## 72 -0.296817278 -0.82761633 -0.6752874
## 73  2.160390349  2.85573606  1.7017243
## 74 -0.488086320 -0.48111093 -0.6752874
## 75  1.148020806  0.33144423 -1.8637932
## 76 -0.343504223 -0.88652225 -0.6752874
## 77  8.222911296 -0.55041201  0.5132184
## 78 -0.082745350  0.29852621 -0.6752874
## 79 -0.302321424 -0.14846575  0.5132184
## 80  0.965007982 -1.24688787 -0.6752874
## 81 -0.462433073 -0.82934886  0.5132184
## 82 -0.378691437 -0.05837435 -0.6752874
## 83 -0.110757517  0.13220362  0.5132184
## 84 -0.291313133 -0.30612571 -0.6752874
## 85 -0.313722867 -0.51749400 -0.6752874
## 86 -0.263300966 -0.76178031 -0.6752874
## 87 -0.261236912 -1.43573331 -1.8637932
## 88 -0.400019999 -0.41527491  0.5132184
## attr(,"scaled:center")
##     lotsize       sqrft       bdrms 
## 9019.863636 2013.693182    3.568182 
## attr(,"scaled:scale")
##       lotsize         sqrft         bdrms 
## 10174.1504141   577.1915827     0.8413926

##Calcular la matriz R

library(stargazer)
n<-nrow(Zn)
R<-cor(X_mat[,-1])
#También se puede calcular R a través de cor(X_mat[,-1])
stargazer(R,type = "html",digits = 4)
## 
## <table style="text-align:center"><tr><td colspan="4" style="border-bottom: 1px solid black"></td></tr><tr><td style="text-align:left"></td><td>lotsize</td><td>sqrft</td><td>bdrms</td></tr>
## <tr><td colspan="4" style="border-bottom: 1px solid black"></td></tr><tr><td style="text-align:left">lotsize</td><td>1</td><td>0.1838</td><td>0.1363</td></tr>
## <tr><td style="text-align:left">sqrft</td><td>0.1838</td><td>1</td><td>0.5315</td></tr>
## <tr><td style="text-align:left">bdrms</td><td>0.1363</td><td>0.5315</td><td>1</td></tr>
## <tr><td colspan="4" style="border-bottom: 1px solid black"></td></tr></table>
print(R)
##           lotsize     sqrft     bdrms
## lotsize 1.0000000 0.1838422 0.1363256
## sqrft   0.1838422 1.0000000 0.5314736
## bdrms   0.1363256 0.5314736 1.0000000

##Calcular |R|

determinante_R<-det(R)
print(determinante_R)
## [1] 0.6917931

#Aplicando la prueba de Farrer Glaubar (Bartlett)

##Estadistico χ2FG

m<-ncol(X_mat[,-1])
n<-nrow(X_mat[,-1])
chi_FG<--(n-1-(2*m+5)/6)*log(determinante_R)
print(chi_FG)
## [1] 31.38122

Valor Critico

gl<-m*(m-1)/2
VC<-qchisq(p = 0.95,df = gl)
print(VC)
## [1] 7.814728

##Regla de Desicion:

Como χ2FG ≥ V.C. se rechaza H0, por lo tanto hay evidencia de colinealidad en los regresores.

##Cálculo de FG usando “mctest”

library(mctest)
mctest::omcdiag(mod = modelo_estimado)
## 
## Call:
## mctest::omcdiag(mod = modelo_estimado)
## 
## 
## Overall Multicollinearity Diagnostics
## 
##                        MC Results detection
## Determinant |X'X|:         0.6918         0
## Farrar Chi-Square:        31.3812         1
## Red Indicator:             0.3341         0
## Sum of Lambda Inverse:     3.8525         0
## Theil's Method:           -0.7297         0
## Condition Number:         11.8678         0
## 
## 1 --> COLLINEARITY is detected by the test 
## 0 --> COLLINEARITY is not detected by the test

##Cálculo de FG usando la “psych”

library(psych)
FG_test<-cortest.bartlett(X_mat[,-1])
## R was not square, finding R from data
print(FG_test)
## $chisq
## [1] 31.38122
## 
## $p.value
## [1] 0.0000007065806
## 
## $df
## [1] 3

#Factores Inflacionarios de la Varianza (FIV)

##Matriz de Correlación de los regresores del modelo

print(R)
##           lotsize     sqrft     bdrms
## lotsize 1.0000000 0.1838422 0.1363256
## sqrft   0.1838422 1.0000000 0.5314736
## bdrms   0.1363256 0.5314736 1.0000000

##Inversa de la matriz de correlación R−1

inversa_R<-solve(R)
print(inversa_R)
##             lotsize      sqrft       bdrms
## lotsize  1.03721145 -0.1610145 -0.05582352
## sqrft   -0.16101454  1.4186543 -0.73202696
## bdrms   -0.05582352 -0.7320270  1.39666321

##VIF’s para el modelo estimado:

VIFs<-diag(inversa_R)
print(VIFs)
##  lotsize    sqrft    bdrms 
## 1.037211 1.418654 1.396663

##Cálculo de los VIF’s usando “performance”

library(performance)
VIFs<-multicollinearity(x = modelo_estimado,verbose = FALSE)
VIFs
## # Check for Multicollinearity
## 
## Low Correlation
## 
##     Term  VIF    VIF 95% CI Increased SE Tolerance Tolerance 95% CI
##  lotsize 1.04 [1.00, 11.02]         1.02      0.96     [0.09, 1.00]
##    sqrft 1.42 [1.18,  1.98]         1.19      0.70     [0.51, 0.85]
##    bdrms 1.40 [1.17,  1.95]         1.18      0.72     [0.51, 0.86]
plot(VIFs)
## Variable `Component` is not in your data frame :/

##Cálculo de los VIF’s usando “car”

library(car)
## Loading required package: carData
## 
## Attaching package: 'car'
## The following object is masked from 'package:psych':
## 
##     logit
VIFs_car<-vif(modelo_estimado)
print(VIFs_car)
##  lotsize    sqrft    bdrms 
## 1.037211 1.418654 1.396663

##Cálculo de los VIF’s usando “mctest”

library(mctest)
mc.plot(mod = modelo_estimado,vif = 2)