R/nonparregtolint.R

In tolerance: Statistical Tolerance Intervals and Regions

npregtol.int <- function (x, y, y.hat, side = 1, alpha = 0.05, P = 0.99, method = c("WILKS", 
    "WALD", "HM"), upper = NULL, lower = NULL) 
{
    method <- match.arg(method)
    n <- length(x)
    if (length(x) != n | length(y) != n | length(y.hat) != n) {
        stop(paste("The predictor vector, response vector, and fitted value vector must all be of the same length!", 
            "\n"))
    }
    res <- y - y.hat
    tol.temp <- nptol.int(res, side = side, alpha = alpha, P = P, 
        method = method, upper = upper, lower = lower)
    out.temp <- list()
    for (i in 1:nrow(tol.temp)) {
        upper <- y.hat + tol.temp[i, 4]
        lower <- y.hat + tol.temp[i, 3]
        temp <- data.frame(cbind(alpha, P, x, y, y.hat, lower, 
            upper))
        if (side == 2) {
            colnames(temp) <- c("alpha", "P", "x", "y", "y.hat", 
                "2-sided.lower", "2-sided.upper")
        }
        else {
            colnames(temp) <- c("alpha", "P", "x", "y", "y.hat", 
                "1-sided.lower", "1-sided.upper")
        }
        index <- which(names(temp) == "y.hat")
        temp <- data.matrix(temp[order(temp[, index]), ], rownames.force = FALSE)
        out.temp[[i]] <- temp
    }
    if (length(out.temp) == 1) 
        out.temp <- out.temp[[i]]
    out.temp <- data.frame(out.temp, check.names = FALSE)
    out.temp
}