R Markdown
Importing GHED Data
ghed_raw <- read_xlsx("GHED_data.xlsx", sheet = "Data") %>%
select(country, code, year,
gghed_usd, gghed_usd2021, gghed_usd2021_pc,
gdp_usd2021_pc, gghed_gdp, gge_gdp) %>%
mutate(est_type = "observed")
# View the resulting data frame
#print(ghed_raw)
Get Logs and Run Fixed Effects Model with PLM (Full Dataset)
# Calculate log values and add them to the data frame
ghed_raw <- ghed_raw %>%
mutate(
log_gdp_pc = log(gdp_usd2021_pc),
log_gghed_pc = log(gghed_usd2021_pc),
contract = ifelse((log_gdp_pc - dplyr::lag(log_gdp_pc)) < 0, 1, 0)
)
fixed_model <- plm(log_gghed_pc ~ log_gdp_pc + contract +
log_gdp_pc*contract , data = ghed_raw,index =
c("country", "year"), model = "within")
Exclude certain countries and years
ghed_filtered <- ghed_raw %>%
mutate(
log_gdp_pc = log(gdp_usd2021_pc),
log_gghed_pc = log(gghed_usd2021_pc),
log_gge_gdp = log(gge_gdp),
contract = ifelse((log_gdp_pc-dplyr::lag(log_gdp_pc))<0,1,0)
) %>%
filter(!(country %in% c("Cuba", "South Sudan", "Venezuela", "Yemen",
"Zimbabwe"))) %>%
filter(!(year %in% c("2020", "2021", "2022"))) %>%
na.omit() # Remove any rows with NA values
model1 <- plm(log_gghed_pc ~ log_gdp_pc, data = ghed_filtered,index =
c("country", "year"), model = "within")
model2 <- plm(log_gghed_pc ~ log_gdp_pc + contract +log_gdp_pc*contract,
data = ghed_filtered,index = c("country", "year"), model = "within")
model3 <- plm(log_gghed_pc ~ log_gdp_pc + contract + log_gdp_pc*contract +
log_gge_gdp + log_gge_gdp*contract,data = ghed_filtered,
index = c("country", "year"), model = "within")
# Use stargazer to display the model summary
stargazer(model1, model2, model3, type="text",align = TRUE,
out = "model_comparison.txt") # Export to a text file)
##
## ========================================================================================================
## Dependent variable:
## -----------------------------------------------------------------------------------
## log_gghed_pc
## (1) (2) (3)
## --------------------------------------------------------------------------------------------------------
## log_gdp_pc 1.269*** 1.276*** 1.161***
## (0.022) (0.022) (0.020)
##
## contract -0.134** -0.064
## (0.057) (0.066)
##
## log_gge_gdp 0.617***
## (0.023)
##
## log_gdp_pc:contract 0.021*** -0.005
## (0.006) (0.006)
##
## contract:log_gge_gdp 0.041**
## (0.019)
##
## --------------------------------------------------------------------------------------------------------
## Observations 3,698 3,698 3,698
## R2 0.493 0.498 0.593
## Adjusted R2 0.466 0.471 0.570
## F Statistic 3,415.132*** (df = 1; 3509) 1,159.300*** (df = 3; 3507) 1,019.727*** (df = 5; 3505)
## ========================================================================================================
## Note: *p<0.1; **p<0.05; ***p<0.01