R/CompK.R

In CHNCapitalStock: Compute Chinese Capital Stocks

#' Compute Capital Stock in Chinese Provinces
#'
#' This function compute capital stock of provinces in China using the method by Zhang (2008) or
#' Chen (2020).
#'
#' @param prv a province name, a scalar character. It's Chinese phonetic alphabets.
#' @param method a string. \code{'ZJ'} by Zhang (2008) or \code{'CP'} by Chen (2020).
#' @param startyr a numeric scalar. When use the method by Chen (2020), \code{delta} is
#' used before \code{startyr}, and after \code{startyr} depreciation in data \code{asset} is used.
#' When use the method by Zhang (2008), the parameters is not useful.
#' @param yr a numeric vector about years. If you only need capital stock before 2017,
#'  you can use its default \code{NULL}. If you need to compute capital stocks in other
#'  years (for example 2018,2019), you can set, for example, \code{yr = c(2018,2019)}.
#' @param invest a numeric vector about investment, its length equal the length of
#' \code{yr}, and its units is 100 million in current price.
#' @param InvestPrice a numeric vector about price indices of investment,
#' its length equal the length of \code{yr}, and it is a fixed base index
#' with equaling 1 in \code{bt}.
#' @param depr a numeric vector about depreciation,its length equal the length of \code{yr},
#' and its units is 100 million in current price. If use the method \code{'ZJ'}, the parameter
#'  is not useful.
#' @param delta a rate of depreciation, a scalar number.

#' @param bt a scalar number, such as 2000. It means computing capital stock with its price equal
#'  1 in \code{bt}
#' @note The parameter \code{InvestPrice} is a fixed base index with equaling 1 in 1952 by default.
#' However, we often only get a price indices of investment with equaling 1
#' in last year. You can use \code{data(asset)} to get \code{InvestPrice}
#' in any year (before 2017) with equaling 1 in 1952. So, it is easy then.
#'
#' @return The function return a data.frame, and its 1st column is province, 2nd column
#'    is year, 3rd column is capital stock, 4th column is the price index of investment.
#' @references Zhang, J., Estimation of China's provincial capital stock (1952-2004) with
#' applications. \emph{Journal of Chinese Economic and Business Studies}, 2008. 6(2): p. 177-196.
#' @examples
#' # Compute capital stock in Xinjiang province in 1952-2017
#' CompK(prv = 'xinjiang')
#' # Compute capital stock in Xinjiang province in 1952-2017 with its price equaling 1 in 2000
#' CompK(prv = 'xinjiang', bt = 2000)
#' # compute capital stock in Beijing in 2018 and 2019
#' CompK(yr = 2018:2019, invest = c(10801.2,11100),
#'    InvestPrice = c(1.86*1.03,1.86*1.03*1.021),
#'    prv = 'beijing',delta = 0.096)
#' # ...
#' # beijing 2018 35023.74246
#' # beijing 2019 37336.21755
#' # Compute capital stock in chongqing with its price equaling 1 in 1992 based on
#' # Chen (2020)
#' CompK(prv = 'chongqing', method = 'CP', startyr = 1996, bt = 1992)
#'
#' @export


CompK <- function(prv, method = 'ZJ', startyr = 1996, yr = NULL, invest = NULL, InvestPrice = NULL,
                     depr = NULL, delta = 0.096,  bt = 1952){
  if (method == 'ZJ'){
    ans <- CompK_ZJ(prv = prv, yr = yr, invest = invest, InvestPrice = InvestPrice,
             delta = delta,  bt = bt)
  }else if (method == 'CP'){
    ans <- CompK_CP(prv = prv, startyr = startyr, yr = yr, invest = invest, InvestPrice = InvestPrice,
                    depr = depr, delta = delta,  bt = bt)
  }
  return(ans)
}