ML1M Data Description – LensKit Codex

Rating Statistics

Ratings	999,480
Users	6,039
Items	3,705
Density	4.467%
Item Gini	0.634
Start Date	2000-04-25 23:25:58
End Date	2003-02-28 17:49:50

Item Statistics

This section describes the distribution of various item statistics from the data set.

Item Popularity

What is the distribution of popularity?

Let’s also look at this as a Lorenz curve, for clarity:

We’ll now fit a distribution.

[distfit] >INFO> fit
[distfit] >INFO> transform
[distfit] >INFO> [pareto  ] [0.00 sec] [RSS: 2.63488e-06] [loc=-222.014 scale=223.014]
[distfit] >INFO> [powerlaw] [0.00 sec] [RSS: 1.92112e-05] [loc=1.000 scale=3426.000]
[distfit] >INFO> [expon   ] [0.00 sec] [RSS: 1.50276e-05] [loc=1.000 scale=268.765]
[distfit] >INFO> [lognorm ] [0.00 sec] [RSS: 6.32251e-07] [loc=-0.765 scale=95.913]
[distfit] >INFO> [pareto  ] [0.00 sec] [RSS: 2.63488e-06] [loc=-222.014 scale=223.014]
[distfit] >INFO> [powerlaw] [0.00 sec] [RSS: 1.92112e-05] [loc=1.000 scale=3426.000]
[distfit] >INFO> [expon   ] [0.00 sec] [RSS: 1.50276e-05] [loc=1.000 scale=268.765]
[distfit] >INFO> [lognorm ] [0.00 sec] [RSS: 6.32251e-07] [loc=-0.765 scale=95.913]
[distfit] >INFO> Compute confidence intervals [parametric]

Summary of fits:

	name	score	loc	scale	arg
0	lognorm	0.000001	-0.765407	95.91261	(1.7014004296924161,)
1	pareto	0.000003	-222.013965	223.013965	(1.6653227769596757,)
2	expon	0.000015	1.0	268.765182	()
3	powerlaw	0.000019	1.0	3426.0	(0.20853226007445616,)