cps78_85 regresyon modeli

library(wooldridge)
library(rmarkdown)
data("cps78_85")
paged_table(cps78_85)
require(dplyr)
## Loading required package: dplyr
## 
## Attaching package: 'dplyr'
## The following objects are masked from 'package:stats':
## 
##     filter, lag
## The following objects are masked from 'package:base':
## 
##     intersect, setdiff, setequal, union
data("cps78_85")
head(cps78_85)
##   educ south nonwhite female married exper expersq union  lwage age year y85
## 1   12     0        0      0       0     8      64     0 1.2150  25   78   0
## 2   12     0        0      1       1    30     900     1 1.6094  47   78   0
## 3    6     0        0      0       1    38    1444     1 2.1401  49   78   0
## 4   12     0        0      0       1    19     361     1 2.0732  36   78   0
## 5   12     0        0      0       1    11     121     0 1.6490  28   78   0
## 6    8     0        0      0       1    43    1849     0 1.7148  56   78   0
##   y85fem y85educ y85union
## 1      0       0        0
## 2      0       0        0
## 3      0       0        0
## 4      0       0        0
## 5      0       0        0
## 6      0       0        0
summary(cps78_85)
##       educ           south           nonwhite          female     
##  Min.   : 1.00   Min.   :0.0000   Min.   :0.0000   Min.   :0.000  
##  1st Qu.:12.00   1st Qu.:0.0000   1st Qu.:0.0000   1st Qu.:0.000  
##  Median :12.00   Median :0.0000   Median :0.0000   Median :0.000  
##  Mean   :12.77   Mean   :0.2943   Mean   :0.1144   Mean   :0.417  
##  3rd Qu.:14.00   3rd Qu.:1.0000   3rd Qu.:0.0000   3rd Qu.:1.000  
##  Max.   :18.00   Max.   :1.0000   Max.   :1.0000   Max.   :1.000  
##     married           exper          expersq           union       
##  Min.   :0.0000   Min.   : 0.00   Min.   :   0.0   Min.   :0.0000  
##  1st Qu.:0.0000   1st Qu.: 8.00   1st Qu.:  64.0   1st Qu.:0.0000  
##  Median :1.0000   Median :15.00   Median : 225.0   Median :0.0000  
##  Mean   :0.6541   Mean   :18.28   Mean   : 499.8   Mean   :0.2435  
##  3rd Qu.:1.0000   3rd Qu.:28.00   3rd Qu.: 784.0   3rd Qu.:0.0000  
##  Max.   :1.0000   Max.   :55.00   Max.   :3025.0   Max.   :1.0000  
##      lwage             age             year            y85        
##  Min.   :-0.470   Min.   :18.00   Min.   :78.00   Min.   :0.0000  
##  1st Qu.: 1.470   1st Qu.:27.00   1st Qu.:78.00   1st Qu.:0.0000  
##  Median : 1.833   Median :34.00   Median :78.00   Median :0.0000  
##  Mean   : 1.867   Mean   :36.54   Mean   :81.45   Mean   :0.4926  
##  3rd Qu.: 2.225   3rd Qu.:46.00   3rd Qu.:85.00   3rd Qu.:1.0000  
##  Max.   : 3.796   Max.   :64.00   Max.   :85.00   Max.   :1.0000  
##      y85fem         y85educ          y85union      
##  Min.   :0.000   Min.   : 0.000   Min.   :0.00000  
##  1st Qu.:0.000   1st Qu.: 0.000   1st Qu.:0.00000  
##  Median :0.000   Median : 0.000   Median :0.00000  
##  Mean   :0.226   Mean   : 6.413   Mean   :0.08856  
##  3rd Qu.:0.000   3rd Qu.:12.000   3rd Qu.:0.00000  
##  Max.   :1.000   Max.   :18.000   Max.   :1.00000
cps78_85 %>%
  group_by(year) %>%
  summarise(veri = n())
## # A tibble: 2 x 2
##    year  veri
##   <int> <int>
## 1    78   550
## 2    85   534
benimdatam <- cps78_85 %>% 
  mutate(y78 = ifelse(year == 1, 0, 1))
summary(benimdatam)
##       educ           south           nonwhite          female     
##  Min.   : 1.00   Min.   :0.0000   Min.   :0.0000   Min.   :0.000  
##  1st Qu.:12.00   1st Qu.:0.0000   1st Qu.:0.0000   1st Qu.:0.000  
##  Median :12.00   Median :0.0000   Median :0.0000   Median :0.000  
##  Mean   :12.77   Mean   :0.2943   Mean   :0.1144   Mean   :0.417  
##  3rd Qu.:14.00   3rd Qu.:1.0000   3rd Qu.:0.0000   3rd Qu.:1.000  
##  Max.   :18.00   Max.   :1.0000   Max.   :1.0000   Max.   :1.000  
##     married           exper          expersq           union       
##  Min.   :0.0000   Min.   : 0.00   Min.   :   0.0   Min.   :0.0000  
##  1st Qu.:0.0000   1st Qu.: 8.00   1st Qu.:  64.0   1st Qu.:0.0000  
##  Median :1.0000   Median :15.00   Median : 225.0   Median :0.0000  
##  Mean   :0.6541   Mean   :18.28   Mean   : 499.8   Mean   :0.2435  
##  3rd Qu.:1.0000   3rd Qu.:28.00   3rd Qu.: 784.0   3rd Qu.:0.0000  
##  Max.   :1.0000   Max.   :55.00   Max.   :3025.0   Max.   :1.0000  
##      lwage             age             year            y85        
##  Min.   :-0.470   Min.   :18.00   Min.   :78.00   Min.   :0.0000  
##  1st Qu.: 1.470   1st Qu.:27.00   1st Qu.:78.00   1st Qu.:0.0000  
##  Median : 1.833   Median :34.00   Median :78.00   Median :0.0000  
##  Mean   : 1.867   Mean   :36.54   Mean   :81.45   Mean   :0.4926  
##  3rd Qu.: 2.225   3rd Qu.:46.00   3rd Qu.:85.00   3rd Qu.:1.0000  
##  Max.   : 3.796   Max.   :64.00   Max.   :85.00   Max.   :1.0000  
##      y85fem         y85educ          y85union            y78   
##  Min.   :0.000   Min.   : 0.000   Min.   :0.00000   Min.   :1  
##  1st Qu.:0.000   1st Qu.: 0.000   1st Qu.:0.00000   1st Qu.:1  
##  Median :0.000   Median : 0.000   Median :0.00000   Median :1  
##  Mean   :0.226   Mean   : 6.413   Mean   :0.08856   Mean   :1  
##  3rd Qu.:0.000   3rd Qu.:12.000   3rd Qu.:0.00000   3rd Qu.:1  
##  Max.   :1.000   Max.   :18.000   Max.   :1.00000   Max.   :1
summary(lm(lwage ~ y78 + y85 + (educ + south) + exper + I(exper^2) + union, data = benimdatam))
## 
## Call:
## lm(formula = lwage ~ y78 + y85 + (educ + south) + exper + I(exper^2) + 
##     union, data = benimdatam)
## 
## Residuals:
##      Min       1Q   Median       3Q      Max 
## -2.47944 -0.27428  0.01622  0.26566  1.98971 
## 
## Coefficients: (1 not defined because of singularities)
##               Estimate Std. Error t value Pr(>|t|)    
## (Intercept)  2.709e-01  8.100e-02   3.344 0.000855 ***
## y78                 NA         NA      NA       NA    
## y85          3.727e-01  2.677e-02  13.922  < 2e-16 ***
## educ         8.097e-02  5.359e-03  15.111  < 2e-16 ***
## south       -5.619e-02  2.946e-02  -1.907 0.056769 .  
## exper        2.896e-02  3.750e-03   7.723 2.59e-14 ***
## I(exper^2)  -3.855e-04  8.155e-05  -4.727 2.58e-06 ***
## union        2.395e-01  3.185e-02   7.519 1.16e-13 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 0.4341 on 1077 degrees of freedom
## Multiple R-squared:  0.364,  Adjusted R-squared:  0.3604 
## F-statistic: 102.7 on 6 and 1077 DF,  p-value: < 2.2e-16
summary(lm(lwage ~ y78 + y85 + (educ + south) + exper + I(exper^2) + union -1, data = benimdatam))
## 
## Call:
## lm(formula = lwage ~ y78 + y85 + (educ + south) + exper + I(exper^2) + 
##     union - 1, data = benimdatam)
## 
## Residuals:
##      Min       1Q   Median       3Q      Max 
## -2.47944 -0.27428  0.01622  0.26566  1.98971 
## 
## Coefficients:
##              Estimate Std. Error t value Pr(>|t|)    
## y78         2.709e-01  8.100e-02   3.344 0.000855 ***
## y85         3.727e-01  2.677e-02  13.922  < 2e-16 ***
## educ        8.097e-02  5.359e-03  15.111  < 2e-16 ***
## south      -5.619e-02  2.946e-02  -1.907 0.056769 .  
## exper       2.896e-02  3.750e-03   7.723 2.59e-14 ***
## I(exper^2) -3.855e-04  8.155e-05  -4.727 2.58e-06 ***
## union       2.395e-01  3.185e-02   7.519 1.16e-13 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 0.4341 on 1077 degrees of freedom
## Multiple R-squared:  0.9505, Adjusted R-squared:  0.9502 
## F-statistic:  2954 on 7 and 1077 DF,  p-value: < 2.2e-16