R/aux_matrix.R

In gnjardim/entrymodels: Estimate Entry Models

#' Build our auxiliary matrices to estimate entry models
#'
#' @param data A \code{data.frame} object containing your data
#' @param y A string indicating the outcome variable
#' @param N_max An \code{integer} indicating the maximum number of competitors
#' @param n Number of observations in \code{data}
#' @return A list of the auxiliary matrices
#'
#' @importFrom dplyr select
#' @importFrom magrittr %>%

aux_matrix <- function(data, y, N_max, n) {

    # auxiliary matrix A1
    A1 <- (-1)*matrix(1, nrow = N_max, ncol = N_max, byrow = TRUE)

    for (i in 1:N_max){
        A1[i,1] <- 1
    }

    for (i in 1:N_max){
        for (j in 1:N_max){
            if (i < j){
                A1[i, j] <- 0
            }
        }
    }

    # auxiliary matrix A2
    A2 <- matrix(1, nrow = N_max, ncol = N_max, byrow = TRUE)

    for (i in 1:N_max){
        for (j in 1:N_max){
            if (i < j){
                A2[i, j] <- 0
            }
        }
    }

    return(list(A1, A2))
}