Question

我是R的新手，想了解它可以为控制图表做些什么。我已经阅读了关于qcc的文章，并根据我自己的数据集在R studio中创建了样本图表，以生成图形或简单的基础数据。

Shewhart控制/运行规则中的两个似乎是在QCC中实现的（+/- 3 sigma和中心上方/下方的字符串），但是已经定义了更多并且经常在实践中使用。 e.g. Nelson rules

是否有实现这些的R库/函数？除了实现规则之外，我还想支持指定＆＃34;常量＆＃34;的选项。与规则有关。例如，引用的文章说＆＃34;连续八个点。＆＃34;我希望八是一个参数。我认为qcc命令的$ data输出可以作为参数传递（与规则向量＆＃34;常量＆＃34;选项一起），作为回报，将是一个违规点列表和规则违反了数字。

有任何想法/建议吗？

Answer 1

在我获得博士学位期间，我正与一名医学微生物学家和血清学家一起工作，我们正在研究在R中实施尼尔森规则。

我认为这正是您所期待的（很高兴分享，我无法在互联网上的其他地方找到R实施）：

nelsonr1 <- function(x, m = mean(x), s = sd(x)) {
    # Nelson's QC rule 1: detect values outside + or -3 sd
    which(abs((x - m) / s) >= 3)
}

nelsonr2 <- function(x, m = mean(x), minrun = 9) {
    # Nelson's QC rule 2: detect runs of >= 9 points on the same side of the mean
    n <- length(x)
    counts <- sign(x - m)
    result <- counts
    for (runlength in 2:minrun)
        result <- result + c(counts[runlength:n], rep(0, runlength - 1))
    which(abs(result) >= minrun)
}

nelsonr3 <- function(x, minrun = 6) {
    # Nelson's QC rule 3: detect strict increase or decrease in >= 6 points in a row
    # Between 6 points you have 5 instances of increasing or decreasing. Therefore minrun - 1.
    n <- length(x)
    signs <- sign(c(x[-1], x[n]) - x)
    counts <- signs
    for (rl in 2:(minrun - 1)) {
        counts <- counts + c(signs[rl:n], rep(0, rl - 1))
    }
    which(abs(counts) >= minrun - 1)
}

nelsonr4 <- function(x, m = mean(x), minrun = 14, directing_from_mean = FALSE) {
    # Nelson's QC rule 4: 14 points in a row alternating in direction from the mean,
    # or 14 points in a row alternating in increase and decrease
    n <- length(x)
    if (directing_from_mean == TRUE) {
        signs <- sign(x - m)
    } else {
        signs <- sign(c(x[-1],x[n]) - x)
    }
    counts <- signs
    fac <- -1
    for (rl in 2:minrun) {
        counts <- counts + fac * c(signs[rl:n], rep(0, rl - 1))
        fac <- -fac
    }
    counts <- abs(counts)
    which(counts >= minrun)
}

nelsonr5 <- function(x, m = mean(x), s = sd(x), minrun = 3) {
    # Nelson's QC rule 5: two out of 3 >2 sd from mean in the same direction
    n <- length(x)
    pos <- 1 * ((x - m) / s > 2)
    neg <- 1 * ((x - m) / s < -2)
    poscounts <- pos
    negcounts <- neg
    for (rl in 2:minrun) {
        poscounts <- poscounts + c(pos[rl:n], rep(0, rl - 1))
        negcounts <- negcounts + c(neg[rl:n], rep(0, rl - 1))
    }
    counts <- apply(cbind(poscounts, negcounts), 1, max)
    which(counts >= minrun -1)
}

nelsonr6 <- function(x, m = mean(x), s = sd(x), minrun = 5) {
    # Nelson's QC rule 6: four out of five > 1 sd from mean in the same direction
    n <- length(x)
    pos <- 1 * ((x - m) / s > 1)
    neg <- 1 * ((x - m) / s < -1)
    poscounts <- pos
    negcounts <- neg
    for (rl in 2:minrun) {
        poscounts <- poscounts + c(pos[rl:n], rep(0, rl - 1))
        negcounts <- negcounts + c(neg[rl:n], rep(0, rl - 1))
    }
    counts <- apply(cbind(poscounts, negcounts), 1, max)
    which(counts >= minrun - 1)
}

nelsonr7 <- function(x, m = mean(x), s = sd(x), minrun = 15) {
    # Nelson's QC rule 7: >= 15 points in a row within 1 sd from the mean
    n <- length(x)
    within <- 1 * (abs((x - m) / s) < 1)
    counts <- within
    for (rl in 2:minrun)
        counts <- counts + c(within[rl:n], rep(0, rl - 1))
    which(counts >= minrun)
}

nelsonr8 <- function(x, m = mean(x), s = sd(x), minrun = 8) {
    # Nelson's QC rule 8: >= 8 points in a row all outside the m + -1s range
    n <- length(x)
    outofrange <- 1 * (abs((x - m) / s) > 1)
    counts <- outofrange
    for (rl in 2:minrun)
        counts <- counts + c(outofrange[rl:n], rep(0, rl - 1))
    which(counts >= minrun)
}

例如，引用的文章中写着“连续八个点......”我希望将八个作为参数。

对于某些函数中的参数minrun，这也是如此。

使用R和qcc实现其他标准运行规则

1 个答案: