package stats / prop.trend.test function

On 12 Nov 2025, at 11.55, Michael Dewey <lists at dewey.myzen.co.uk> wrote:

Dear Paulo

You did realise that if you type prop.trend.test you get

function (x, n, score = seq_along(x))
{
   method <- "Chi-squared Test for Trend in Proportions"
   dname <- paste(deparse1(substitute(x)), "out of", deparse1(substitute(n)),
       ",\n using scores:", paste(score, collapse = " "))
   x <- as.vector(x)
   n <- as.vector(n)
   p <- sum(x)/sum(n)
   w <- n/p/(1 - p)
   a <- anova(lm(freq ~ score, data = list(freq = x/n, score = as.vector(score)),
       weights = w))
   chisq <- c(`X-squared` = a["score", "Sum Sq"])
   structure(list(statistic = chisq, parameter = c(df = 1),
       p.value = pchisq(as.numeric(chisq), 1, lower.tail = FALSE),
       method = method, data.name = dname), class = "htest")
}
<bytecode: 0x0000021d81d4c850>
<environment: namespace:stats>

Does that help?

Michael

On 11/11/2025 18:27, Paulo Barata wrote:

To the R-Help list,
About the prop.trend.test function, in the package stats.
What calculations exactly does that function perform? What test is actually carried out? May I have some reference for the calculations performed by that function?
I would like to suggest that some references (one or more) be included in the Help file for the function.
Thank you very much.
Paulo Barata
Rio de Janeiro - Brazil

-- 
Michael Dewey