FWIW, the mean of the min and max is called the midrange. — John
On Jul 22, 2014, at 8:17 AM, Spencer Russell <[email protected]> wrote: > Hi Elliot, > > The median isn't the mean of the min and max (though that was fun to say). > > Wikipedia says it well: > > "the median is the numerical value separating the higher half of a data > sample, a population, or a probability distribution, from the lower half. The > median of a finite list of numbers can be found by arranging all the > observations from lowest value to highest value and picking the middle one > (e.g., the median of {3, 3, 5, 9, 11} is 5). If there is an even number of > observations, then there is no single middle value; the median is then > usually defined to be the mean of the two middle values" > > peace, > s > > > On Tue, Jul 22, 2014 at 10:27 AM, Ivar Nesje <[email protected]> wrote: > According to Julia median is defined as > > n = length(v) > if isodd(n) > return middle(select!(v,div(n+1,2))) > else > m = select!(v, div(n,2):div(n,2)+1) > return middle(m[1], m[2]) > end > > Ivar > > kl. 16:03:47 UTC+2 tirsdag 22. juli 2014 skrev Elliot Saba følgende: > Reading your post, I'm a little confused Iain. You state: > > If we consider only packages with at least 1 package depending on them, we > find the median to be 3 dependent packages but the mean to be 10.5. This is > due to the 15 or so packages with more than 30 dependent packages. > > Now, I'm not the best at statistics, but isn't the median of x defined as > (min(x) + max(x))/2? If that is the case, (and assuming that we don't have > negative package dependency counts) I don't see how the median can be 3, but > the mean be 10.5. Perhaps you meant the mode was 3? > -E > > > On Tue, Jul 22, 2014 at 9:55 AM, Iain Dunning <[email protected]> wrote: > Hah, yeah, strangely relevant. > PkgEval runs nightly (around 1am US Eastern), but obviously with so many > people using Julia there is a lot of room for chaos inbetween runs. > > > On Tuesday, July 22, 2014 7:58:46 AM UTC-4, Tomas Lycken wrote: > Look what my RSS reader just picked up! =) > > http://iaindunning.com/2014/pkg-deps.html > > // T > > On Tuesday, July 22, 2014 12:37:59 PM UTC+2, Tomas Lycken wrote: > I still think the best way to resolve things if you should encounter > problems, is to notify the maintainers. Most people in this community respond > surprisingly fast =) > > There is some automated testing going on already, mainly thanks to [Iain > Dunning](https://github.com/IainNZ)'s amazing work with PackageEvaluator and > related tools. For example, if you click "more options" on pkg.julialang.org > and then "Show package ecosystem statistics for Julia nightly...", you'll see > some great data showing the current (and past) state of the entire ecosystem. > You'll notice a few dips in the green curve, when changes somewhere suddenly > broke a lot of stuff everywhere - and you'll also see that most of it was > resolved in a matter of a few days. This happened because semi-automated > issues were filed by the system against the packages when they broke, and > maintainers were quick to fix whatever they needed. > > In the case of your problems - someone tagging a version without specifying a > correct dependency - that will also be picked up by PkgEval, and the > maintainer will be notified. However, since PkgEval only runs every now and > then, and since quite a lot of users today "live on the edge" (and actively > report issues when they find them) it's not uncommon that problems like this > are picked up by users before PkgEval notices them. It's very likely that, as > the ecosystem matures and stabilizes, this problem won't be a problem > anymore... > > // T > > On Tuesday, July 22, 2014 11:47:32 AM UTC+2, Andreas Lobinger wrote: > Hello colleagues, > > On Monday, July 21, 2014 4:53:17 PM UTC+2, Tomas Lycken wrote: > I think this problem must be resolved by better practices among package > maintainers: in short, the goal must be that as long as you only use (the > latest) tagged versions of any packages, everything should Just Work (TM). > That means, in short, that if a package maintainer adds functionality that > depends on some specific addition to a different package, it is up to that > package maintainer to make sure not to tag a new version until the dependency > package has tagged one, in which the new behavior is included, so the > dependency can be correctly specified. > > > ... in an ideal world. All that we use around julia has a version number less > than 1.0 so hiccups are expected (at least by me). The question was rather > how i can help myself and if there is some undocumented work assumption. If i > ever publish a package i'll try hard to follow your advice. > > This interdependency things showed up also in the great julia-graphics thread > on julia-dev. Maybe some automatic testing could help? Maybe some dependency > graph could be extracted out of the METADATA? > > Wishing a happy day, > > >
