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density with weights missing values

Göran Broström 
Den 2021-07-12 kl. 15:09, skrev Matthias Gondan:
One difference is that density has a named argument 'weights' not 
present in weighted.mean, which instead has 'w' for weights.
Annoying.

So, in your examples, the argument 'weights = ' is always ignored, at 
least for weighted.mean.default:

 > stats:::weighted.mean.default
function (x, w, ..., na.rm = FALSE)
{
     if (missing(w)) {
         if (na.rm)
             x <- x[!is.na(x)]
         return(sum(x)/length(x))
     }
     if (length(w) != length(x))
         stop("'x' and 'w' must have the same length")
     if (na.rm) {
         i <- !is.na(x)
         w <- w[i]
         x <- x[i]
     }
     sum((x * w)[w != 0])/sum(w)
}

But, using 'w' for weights, missing values in weights will work only if 
na.rm = TRUE and they match missing values in x. As documented.

[...]
and no warning for sum(w) != 1

That's because the weights w are normalized (after removing weights 
corresponding to missing values in x).

G,

Thread (11 messages)

Matthias Gondan density with weights missing values Jul 12 Bert Gunter density with weights missing values Jul 12 Matthias Gondan density with weights missing values Jul 12 Bert Gunter density with weights missing values Jul 12 Jeff Newmiller density with weights missing values Jul 12 Matthias Gondan density with weights missing values Jul 12 Jeff Newmiller density with weights missing values Jul 12 Duncan Murdoch density with weights missing values Jul 12 Martin Maechler density with weights missing values Jul 13 Matthias Gondan density with weights missing values Jul 13 Göran Broström density with weights missing values Jul 13