Shapiro-Wilk常态测试:功能C_SWilk

时间:2014-08-21 09:19:42

标签: r function stat normal-distribution

我试图找出在R中执行Shapiro-Wilk正态性测试时究竟如何计算测试统计量。这是函数的主体。

> shapiro.test
function (x) 
{
    DNAME <- deparse(substitute(x))
    stopifnot(is.numeric(x))
    x <- sort(x[complete.cases(x)])
    n <- length(x)
    if (is.na(n) || n < 3L || n > 5000L) 
        stop("sample size must be between 3 and 5000")
    rng <- x[n] - x[1L]
    if (rng == 0) 
        stop("all 'x' values are identical")
    if (rng < 1e-10) 
        x <- x/rng
    res <- .Call(C_SWilk, x)
    RVAL <- list(statistic = c(W = res[1]), p.value = res[2], 
        method = "Shapiro-Wilk normality test", data.name = DNAME)
    class(RVAL) <- "htest"
    return(RVAL)
}
<bytecode: 0x0603f2a8>
<environment: namespace:stats>

我无法理解这一部分:

.Call(C_SWilk, x)

似乎调用了一个函数(即C_SWilk)。有谁知道这个功能是什么?我试着看,但它给了我一个错误,

> C_SWilk
Error: object 'C_SWilk' not found

0 个答案:

没有答案