"Informative" is the adjective form of "information". What's the adjective form of "data"/"datum"?

This really should be implemented: it is good for the sites, it is good netizenship, people want this, and an implementation already exists. As far as I can tell - from any publicly available information - all that's needed is (in essence) for SE to flip a switch. Just to sum up some responses, ...

One long-standing feature requests for the Stack Exchange engine is the implementation of trackbacks for mentions of the arXiv on Stack Exchange sites. In general, if you have a blog and you blog about an arXiv eprint, you can send the arXiv a specially crafted http message, and then your blog ge...

One long-standing feature requests for the Stack Exchange engine is the implementation of trackbacks for mentions of the arXiv on Stack Exchange sites. In general, if you have a blog and you blog about an arXiv eprint, you can send the arXiv a specially crafted http message, and then your blog ge...

One long-standing feature requests for the Stack Exchange engine is the implementation of trackbacks for mentions of the arXiv on Stack Exchange sites. In general, if you have a blog and you blog about an arXiv eprint, you can send the arXiv a specially crafted http message, and then your blog ge...

The bounty asks (taking things a bit out of order) Can the SE team comment on the status of the roll-out to other SE sites? Alright, here goes. If this is status-declined, can we have an official statement and some thoughts as to the reason? First off, the good (or less bad) news: thi...

It is not necessarily true that the closure of an open ball $B_{r}(x)$ is equal to the closed ball of the same radius $r$ centered at the same point $x$. For a quick example, take $X$ to be any set and define a metric $$ d(x,y)= \begin{cases} 0\qquad&\text{if and only if $x=y$}\\ 1&\text{otherwis...