TWFE.R

############################################
# SETTING UP FOR DIFFERENCE-IN-DIFFERENCES #
############################################

load("dn.rda")

fworkers_12 <- dn %>% 
  filter(year == 2012) %>% 
  select(tinh, huyen, xa, madn, ma_thue, f_ss) %>% 
  rename(fworkers_12 = f_ss)

dn0818 <- c("dn08", "dn09", "dn10", "dn11", "dn12", "dn13", "dn14", "dn15", "dn16", "dn17", "dn18")

for(i in dn0818){
  
  if(i %in% c("dn13", "dn14", "dn15")){
    
    assign(i, left_join(get(i), fworkers_12, by = c("tinh", "huyen", "xa", "madn", "ma_thue")))
    
  }
  
  if(i %in% c("dn16", "dn17", "dn18")){
    
    assign(i, left_join(get(i), fworkers_12, by = c("tinh", "huyen", "xa", "ma_thue")))
    
  }  
  
}

dn12 <- dn12 %>% mutate(fworkers_12 = f_ss)

dn1218 <- bind_rows(dn12, dn13, dn14, dn15, dn16, dn17, dn18) %>% 
  group_by(tinh, huyen, xa, ma_thue) %>% 
  mutate(id = cur_group_id()) %>% 
  mutate(post = ifelse(year > 2012, 1, 0),
         did = post*fworkers_12,
         did = ifelse(year == 2012, 0, did))

duplicates <- dn1218 %>% dplyr::group_by(tinh, huyen, xa, madn, ma_thue, id, fworkers_12, year) %>%
  dplyr::summarise(n = dplyr::n(), .groups = "drop") %>%
  dplyr::filter(n > 1L) %>% 
  select(tinh, huyen, xa, madn, ma_thue, id)
  

dn1218 <- anti_join(dn1218, duplicates, by = c("tinh", "huyen", "xa", "madn", "ma_thue", "id"))

save(dn1218, file = "dn1218.rda")

##############################
# SETTING UP FOR EVENT STUDY #
##############################

for(i in dn0818){
  
  if(i %in% c("dn08", "dn09", "dn10", "dn11")){
    
    assign(i, left_join(get(i), fworkers_12, by = c("tinh", "huyen", "xa", "madn", "ma_thue")))
    
  }
  
}

dn0815 <- bind_rows(dn08, dn09, dn10, dn11, dn12, dn13, dn14, dn15, dn16, dn17, dn18) %>% 
  group_by(tinh, huyen, xa, ma_thue) %>% 
  mutate(id = cur_group_id())

duplicates <- dn0815 %>% dplyr::group_by(tinh, huyen, xa, madn, ma_thue, id, fworkers_12, year) %>%
  dplyr::summarise(n = dplyr::n(), .groups = "drop") %>%
  dplyr::filter(n > 1L) %>% 
  select(tinh, huyen, xa, madn, ma_thue, id)

dn0815 <- anti_join(dn0815, duplicates, by = c("tinh", "huyen", "xa", "madn", "ma_thue", "id"))

save(dn0815, file = "dn0815.rda")

#######################################################
# ROBUSTNESS USING 2011 FEMALE SHARE OF WORKERS W. SS #
#######################################################

fworkers_11 <- dn11 %>% 
  select(tinh, huyen, xa, madn, ma_thue, f_ss) %>% 
  rename(fworkers_11 = f_ss)

dn11 <- dn11 %>% mutate(fworkers_11 = f_ss)

for(i in dn0818){
  
  if(i %in% c("dn08", "dn09", "dn10", "dn12", "dn13", "dn14", "dn15","dn16", "dn17", "dn18")){
    
    assign(i, left_join(get(i), fworkers_11, by = c("tinh", "huyen", "xa", "madn", "ma_thue")))
    
  }
  
}

dn1218_robust <- bind_rows(dn12, dn13, dn14, dn15, dn16, dn17, dn18) %>% 
  group_by(tinh, huyen, xa, ma_thue) %>% 
  mutate(id = cur_group_id()) %>% 
  mutate(post = ifelse(year > 2012, 1, 0),
         did = post*fworkers_11) %>% 
  mutate(did = ifelse(year == 2012, 0, did))

duplicates <- dn1218_robust %>% dplyr::group_by(tinh, huyen, xa, madn, ma_thue, id, fworkers_11, year) %>%
  dplyr::summarise(n = dplyr::n(), .groups = "drop") %>%
  dplyr::filter(n > 1L) %>% 
  select(tinh, huyen, xa, madn, ma_thue, id)

dn1218_robust <- anti_join(dn1218_robust, duplicates, by = c("tinh", "huyen", "xa", "madn", "ma_thue", "id"))

dn0818_robust <- bind_rows(dn08, dn09, dn10, dn11, dn12, dn13, dn14, dn15, dn16, dn17, dn18) %>% 
  group_by(tinh, huyen, xa, ma_thue) %>% 
  mutate(id = cur_group_id())

duplicates <- dn0818_robust %>% dplyr::group_by(tinh, huyen, xa, madn, ma_thue, id, fworkers_11, year) %>%
  dplyr::summarise(n = dplyr::n(), .groups = "drop") %>%
  dplyr::filter(n > 1L) %>% 
  select(tinh, huyen, xa, madn, ma_thue, id)

dn0818_robust <- anti_join(dn0818_robust, duplicates, by = c("tinh", "huyen", "xa", "madn", "ma_thue", "id"))

save(dn1218_robust, file = "dn1218_robust.rda")
save(dn0818_robust, file = "dn0818_robust.rda")

########
# TWFE #
########

load("dn1218.rda")

setFixest_dict(c("n_workers" = "No. of workers",
         "fworkers_eoy" = "Share of workers, female",
         "n_informal" = "No. of informal workers",
         "finformal" = "Share of informal workers, female",
         "n_workers_ss" = "Share of workers receiving SS",
         "f_ss" = "Share of workers receiving SS, female"))

etable(list(
  feols(log(n_workers) ~ fworkers_12 + post + did | id,
        dn1218),  
  feols(fworkers_eoy ~ fworkers_12 + post + did | id,
        dn1218),
  feols(log(n_informal) ~ fworkers_12 + post + did | id,
        dn1218),  
  feols(finformal ~ fworkers_12 + post + did | id,
        subset(dn1218, year < 2016)),
  feols(log(n_workers_ss) ~ fworkers_12 + post + did | id,
        subset(dn1218, year < 2016)),
  feols(f_ss ~ fworkers_12 + post + did | id,
        subset(dn1218, year < 2016))
  ), tex = T)

# Robustness check 

etable(list(
  feols(log(n_workers) ~ fworkers_11 + post + did | id,
        dn1218_robust),  
  feols(fworkers_eoy ~ fworkers_11 + post + did | id,
        dn1218_robust),
  feols(log(n_informal) ~ fworkers_11 + post + did | id,
        dn1218_robust),  
  feols(finformal ~ fworkers_11 + post + did | id,
        subset(dn1218_robust, year < 2016)),
  feols(log(n_workers_ss) ~ fworkers_11 + post + did | id,
        subset(dn1218_robust, year < 2016)),
  feols(log(n_workers_ss) ~ fworkers_11 + post + did | id,
        subset(dn1218_robust, year < 2016)),
  feols(f_ss ~ fworkers_11 + post + did | id,
        subset(dn1218_robust, year < 2016))
), tex = T)

###############
# EVENT STUDY #
###############

load("dn0815.rda")

setFixest_coefplot(grid = F, zero.par = list(type="dotted", col = "darkblue", lty = 2), main = "")

png("es_nworkers.png")
iplot(feols(log(n_workers) ~ i(year, fworkers_12, 2012) | id + year,
            dn0815,
            vcov = ~id), xlab = "Year")
dev.off()

png("es_nworkers_robust.png")
iplot(feols(log(n_workers) ~ i(year, fworkers_11, 2012) | id + year,
            dn0818_robust,
            vcov = ~id), xlab = "Year")
dev.off()

png("es_n_informal.png")
iplot(feols(log(n_informal) ~ i(year, fworkers_12, 2012) | id + year,
            dn0815,
            vcov = ~id), xlab = "Year")
dev.off()

png("es_n_informal_robust.png")
iplot(feols(log(n_informal) ~ i(year, fworkers_11, 2012) | id + year,
            dn0818_robust,
            vcov = ~id), xlab = "Year")
dev.off()

png("es_fworkers_eoy.png")
iplot(feols(fworkers_eoy ~ i(year, fworkers_12, 2012) | id + year,
            dn0815,
            vcov = ~id), xlab = "Year")
dev.off()

iplot(feols(fworkers_eoy ~ i(year, fworkers_11, 2012) | id + year,
            dn0818_robust,
            vcov = ~id), xlab = "Year")

png("es_finformal.png")
iplot(feols(finformal ~ i(year, fworkers_12, 2012) | id + year,
            subset(dn0818_robust, year < 2016),
            vcov = ~id), xlab = "Year")
dev.off()

png("es_finformal_robust.png")
iplot(feols(finformal ~ i(year, fworkers_11, 2012) | id + year,
            subset(dn0815, year < 2016),
            vcov = ~id), xlab = "Year")
dev.off()

png("es_n_workers_ss.png")
iplot(feols(log(n_workers_ss) ~ i(year, fworkers_12, 2012) | id + year,
            dn0815,
            vcov = ~id), xlab = "Year")
dev.off()

png("es_n_workers_ss_robust.png")
iplot(feols(log(n_workers_ss) ~ i(year, fworkers_11, 2012) | id + year,
            dn0818_robust,
            vcov = ~id), xlab = "Year")
dev.off()

png("es_f_ss.png")
iplot(feols(f_ss ~ i(year, fworkers_12, 2012) | id + year,
            subset(dn0815, year < 2016),
            vcov = ~id), xlab = "Year")
dev.off()

png("es_f_ss_robust.png")
iplot(feols(f_ss ~ i(year, fworkers_11, 2012) | id + year,
            subset(dn0818_robust, year < 2016),
            vcov = ~id), xlab = "Year")
dev.off()

png("es_wage.png")
iplot(feols(log(wage) ~ i(year, fworkers_12, 2012) | id + year,
            dn0815), xlab = "Year")
dev.off()

png("es_wage_robust.png")
iplot(feols(log(wage) ~ i(year, fworkers_11, 2012) | id + year,
            dn0818_robust), xlab = "Year")
dev.off()

png("es_ss.png")
iplot(feols(log(ss_cont) ~ i(year, fworkers_12, 2012) | id + year,
            dn0815), xlab = "Year")
dev.off()

png("es_ss_robust.png")
iplot(feols(log(ss_cont) ~ i(year, fworkers_11, 2012) | id + year,
            dn0818_robust), xlab = "Year")
dev.off()

png("es_profit.png")
iplot(feols(log(pretax_profit) ~ i(year, fworkers_12, 2012) | id + year,
            dn0815), xlab = "Year")
dev.off()

png("es_profit_robust.png")
iplot(feols(log(pretax_profit) ~ i(year, fworkers_11, 2012) | id + year,
            dn0818_robust), xlab = "Year")
dev.off()