HN Explorer

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mechanical_fish
Based on this other URL:

http://www.indeed.com/jobtrends?q=ruby%2C+drupal&l=

and some clicking back and forth between the "Absolute" and "Relative" scales... I don't know what to think. The "Relative" numbers make no sense, so I wouldn't trust them for any purpose whatsoever. "Percentage growth: 375000?" I wish I could erase those graphs from my mind lest my subconscious be tainted by the memory of a single pixel.

Someone needs some unit tests, or perhaps a math teacher.

lunchbox
Example: at the beginning of the time period there was 1 Drupal posting, and now there are 3751. Each increase of 1 represents an additional 100% growth over the original, so you have 3750 * 100% = 375,000% growth.

A poor way to measure rapid growth, but that seems to be their system.

mechanical_fish
I think you're probably correct, but "poor" is much too generous a description of such a methodology. It rates at least an "awful", and "garbage" is not unwarranted.

Consider that it is only an accident of fate that there was merely 1 Drupal posting at time 0. If there had been two, I guess the entire trendline would be half as big.

Or consider this even wackier example:

http://www.indeed.com/jobtrends?q=ruby%2C+mongodb&l=&...

This goes to show that the algorithm is at least smart enough not to explode when dividing by zero. (There were, I'm pretty sure, zero mentions of "MongoDB" in job postings in 2005.) But, then, what does this graph measure? What are we dividing by for MongoDB? The number of postings at some arbitrary later time?

xanderhud
What's the proper way to do this?
tamersalama
How are fluctuations calculated if the reference is the start point? Could these be 'deleted' posts?
fauigerzigerk
Exactly. It would be useful if you could set the starting point of the period you're interested in.
lunchbox
That trend is relative. Here it is in absolute terms:

http://www.indeed.com/jobtrends?q=ruby,+java,+python,+perl&#...

Ruby started out with hardly any postings, so its relative growth is astronomical.

teaspoon
Any Ruby vs. Python comparison here is probably tainted by the fact that Rails often becomes "Ruby and Rails" or even just "Ruby" in recruiterspeak. You don't see a lot of reqs for "Python and Django" or "Python and Tornado".
donw
The 'relative' graph is rubbish. The 'absolute' graph says something that I think is fairly obvious: If you want a job, you'll have an easier time finding it if you can write Java (or C++, or C#).

I did a bit of clicking around, and most of the Ruby jobs were for Ruby on Rails, which is a little disappointing, but not surprising.

Most of the Python jobs seem to mention python as a secondary skill next to PHP, or are otherwise a massive mash of keywords. Which is even more disappointing; even though I'm more of a Ruby guy, Python is an excellent language for any serious number crunching. I can't think of anything in any other general-purpose language that comes close to SciPy/NumPy.