ivreg (version 0.5-0)

CigaretteDemand: U.S. Cigarette Demand Data

Description

Determinants of cigarette demand for the 48 continental US States in 1995 and compared between 1995 and 1985.

Usage

data("CigaretteDemand", package = "ivreg")

Format

A data frame with 48 rows and 10 columns.

packs

Number of cigarette packs per capita sold in 1995.

rprice

Real price in 1995 (including sales tax).

rincome

Real per capita income in 1995.

salestax

Sales tax in 1995.

cigtax

Cigarette-specific taxes (federal and average local excise taxes) in 1995.

packsdiff

Difference in log(packs) (between 1995 and 1985).

pricediff

Difference in log(rprice) (between 1995 and 1985).

incomediff

Difference in log(rincome) (between 1995 and 1985).

salestaxdiff

Difference in salestax (between 1995 and 1985).

cigtaxdiff

Difference in cigtax (between 1995 and 1985).

Details

The data are taken from the online complements to Stock and Watson (2007) and had been prepared as panel data (in long form) in CigarettesSW from the AER package (Kleiber and Zeileis 2008). Here, the data are provided by state (in wide form), readily preprocessed to contain all variables needed for illustrations of OLS and IV regressions. More related examples from Stock and Watson (2007) are provided in the AER package in StockWatson2007. A detailed discussion of the various cigarette demand examples with R code is provided by Hanck et al. (2020, Chapter 12).

References

Hanck, C., Arnold, M., Gerber, A., and Schmelzer, M. (2020). Introduction to Econometrics with R. https://www.econometrics-with-r.org/

Kleiber, C. and Zeileis, A. (2008). Applied Econometrics with R. Springer-Verlag

Stock, J.H. and Watson, M.W. (2007). Introduction to Econometrics, 2nd ed., Addison Wesley.

See Also

CigarettesSW.

Examples

# NOT RUN {
## load data
data("CigaretteDemand", package = "ivreg")

## basic price elasticity: OLS vs. IV
cig_ols <- lm(log(packs) ~ log(rprice), data = CigaretteDemand)
cig_iv <- ivreg(log(packs) ~ log(rprice) | salestax, data = CigaretteDemand)
cbind(OLS = coef(cig_ols), IV = coef(cig_iv))

## adjusting for income differences (exogenous)
cig_iv2 <- ivreg(log(packs) ~ log(rprice) + log(rincome) | salestax + log(rincome),
  data = CigaretteDemand)
## adding a second instrument for log(rprice)
cig_iv3 <- update(cig_iv2, . ~ . | . + cigtax)

## comparison using heteroscedasticity-consistent standard errors
library("lmtest")
library("sandwich")
coeftest(cig_iv2, vcov = vcovHC, type = "HC1")
coeftest(cig_iv3, vcov = vcovHC, type = "HC1")

## long-run price elasticity using differences between 1995 and 1985
cig_ivdiff1 <- ivreg(packsdiff ~ pricediff + incomediff | incomediff + salestaxdiff,
  data = CigaretteDemand)
cig_ivdiff2 <- update(cig_ivdiff1, . ~ . | . - salestaxdiff + cigtaxdiff)
cig_ivdiff3 <- update(cig_ivdiff1, . ~ . | . + cigtaxdiff)
coeftest(cig_ivdiff1, vcov = vcovHC, type = "HC1")
coeftest(cig_ivdiff2, vcov = vcovHC, type = "HC1")
coeftest(cig_ivdiff3, vcov = vcovHC, type = "HC1")
# }