Genre Average Song Lengths

I was working on a different post and had to write a script to get the average song length of a genre from last.fm. I wrote a quick perl script and figured I'd get some other genres to compare. I grabbed the 250 top tags, and then grabbed the 50 top tracks for each tag.

I didn't really expect anything revolutionary.  Prog has longer songs than punk.  Some of the tags don't represent genres (eg Live), but I didn't remove them, both because they are interesting too, and I'm lazy.  Here are the results.

There's a slight positive correlation (0.23) between song length and ranking.  That is, longer genres are generally less popular.  Mean and median length across all genres are quite close at 4:20, and 4:14 respectively.

A graph and table of the top 50 most popular:

Rank	Genre	Average Length
48	progressive metal	6:40
26	progressive rock	6:02
15	ambient	5:45
24	black metal	5:38
42	trance	5:29
36	classical	5:24
29	heavy metal	5:14
40	thrash metal	5:14
49	trip-hop	5:08
19	hard rock	4:51
9	classic rock	4:48
44	favorites	4:47
11	jazz	4:38
27	death metal	4:34
25	chillout	4:33
17	experimental	4:32
50	hip hop	4:31
7	metal	4:30
45	reggae	4:29
33	industrial	4:28
10	alternative rock	4:25
38	rap	4:18
18	electronica	4:16
43	japanese	4:16
41	metalcore	4:14
1	rock	4:13
3	alternative	4:11
16	singer-songwriter	4:08
28	instrumental	4:06
5	electronic	4:04
14	folk	4:04
39	90s	4:02
21	80s	4:00
8	female vocalists	3:58
22	dance	3:55
20	hip-hop	3:54
30	british	3:52
46	acoustic	3:50
4	indie	3:46
6	pop	3:45
2	seen live	3:41
37	emo	3:41
34	soul	3:40
13	indie rock	3:39
47	country	3:38
35	blues	3:28
31	punk rock	3:26
32	soundtrack	3:16
23	hardcore	3:09
12	punk	2:58