Multiple Linear Regression Model

Purpose of this post is to explain Frisch-Waught in a very simple form as many a times students in econometric classes are used to memorize the concept \(y=\beta_0x+\beta_1x_1+\beta_2x_2+\epsilon\) Using the data set Growth described (description is provided in previous video), excluding the data for Malta, run the following five regressions: Growth on
(1) TradeShare and YearsSchool;

library(readxl)
library(dplyr)
library(moderndive)
library(gridExtra)
library(ggplot2)
library(stargazer)

Growth <- read_excel("C:/Users/hp/Dropbox/Applied Economics/Growth.xlsx")

glimpse(Growth)
## Observations: 65
## Variables: 7
## $ country_name  <chr> "India", "Argentina", "Japan", "Brazil", "United Stat...
## $ growth        <dbl> 1.9151680, 0.6176451, 4.3047590, 2.9300970, 1.7122650...
## $ rgdp60        <dbl> 765.9998, 4462.0010, 2954.0000, 1784.0000, 9895.0040,...
## $ tradeshare    <dbl> 0.1405020, 0.1566230, 0.1577032, 0.1604051, 0.1608150...
## $ yearsschool   <dbl> 1.45, 4.99, 6.71, 2.89, 8.66, 0.79, 3.80, 2.97, 3.02,...
## $ rev_coups     <dbl> 0.1333333, 0.9333333, 0.0000000, 0.1000000, 0.0000000...
## $ assasinations <dbl> 0.8666667, 1.9333330, 0.2000000, 0.1000000, 0.4333333...
growth_malta<-Growth %>% filter(country_name!="Malta")

mod.lm1<-lm(growth~tradeshare+yearsschool,data = growth_malta)
#mod.lm2<-lm(growth~yearsschool,data = growth_malta)
#mod.lm3<-lm(tradeshare~yearsschool,data = growth_malta)
#gr_yrs<-mod.lm2$residuals
#trsh_yrs<-mod.lm3$residuals
#mod.lm4<-lm(gr_yrs~trsh_yrs)
#get_regression_table(mod.lm1)
#get_regression_table(mod.lm4)

#stargazer(mod.lm1,mod.lm4,type = "text")

Using the data set Growth described (description is provided in class notes), excluding the data for Malta, run the following five regressions: Growth on
(1) TradeShare and YearsSchool; (2) TradeShare and ln(YearsSchool); (3) TradeShare, ln(YearsSchool), Rev_Coups, Assassinations and ln(RGDP60); (4) TradeShare, ln(YearsSchool), Rev_Coups, Assassinations, ln(RGDP60), and TradeShare*Yearsschool; and

mod.lm1<-lm(growth~tradeshare+yearsschool,data = growth_malta)## Part_a
growth_malta<-growth_malta %>% mutate(lnYearSch=log(yearsschool),lnrgdp60=log(rgdp60))
mod.lm2<-lm(growth~tradeshare+lnYearSch,growth_malta)   ##Part_b
mod.lm3<-lm(growth~tradeshare+lnYearSch+rev_coups+assasinations+lnrgdp60,data = growth_malta)
mod.lm4<-lm(growth~tradeshare+lnYearSch+rev_coups+assasinations+lnrgdp60+tradeshare*yearsschool,data = growth_malta)
stargazer(mod.lm1,mod.lm2,mod.lm3,mod.lm4,type = "text")
## 
## ===============================================================================================================
##                                                          Dependent variable:                                   
##                        ----------------------------------------------------------------------------------------
##                                                                 growth                                         
##                                 (1)                   (2)                    (3)                   (4)         
## ---------------------------------------------------------------------------------------------------------------
## tradeshare                    1.898**               1.749**                 1.104                 1.640        
##                               (0.936)               (0.860)                (0.833)               (1.550)       
##                                                                                                                
## yearsschool                  0.243***                                                            -0.144        
##                               (0.084)                                                            (0.248)       
##                                                                                                                
## tradeshare:yearsschool                                                                           -0.201        
##                                                                                                  (0.329)       
##                                                                                                                
## lnYearSch                                           1.016***              2.161***              2.626***       
##                                                     (0.223)                (0.363)               (0.495)       
##                                                                                                                
## rev_coups                                                                 -2.300**              -2.297**       
##                                                                            (1.004)               (1.003)       
##                                                                                                                
## assasinations                                                               0.228                 0.061        
##                                                                            (0.434)               (0.451)       
##                                                                                                                
## lnrgdp60                                                                  -1.621***             -1.406***      
##                                                                            (0.399)               (0.433)       
##                                                                                                                
## Constant                      -0.122                 -0.186               11.746***             10.330***      
##                               (0.663)               (0.564)                (2.920)               (3.068)       
##                                                                                                                
## ---------------------------------------------------------------------------------------------------------------
## Observations                    64                     64                    64                    64          
## R2                             0.161                 0.287                  0.453                 0.474        
## Adjusted R2                    0.133                 0.264                  0.406                 0.408        
## Residual Std. Error       1.691 (df = 61)       1.558 (df = 61)        1.400 (df = 58)       1.397 (df = 56)   
## F Statistic            5.836*** (df = 2; 61) 12.287*** (df = 2; 61) 9.613*** (df = 5; 58) 7.208*** (df = 7; 56)
## ===============================================================================================================
## Note:                                                                               *p<0.1; **p<0.05; ***p<0.01