GoRec

blog: https://lapis-zero09.hatenablog.com/entry/2018/05/06/171536

Methods

• User/Item base
  • Pearson
  • Cosine
  • Adjusted Cosine
  • Jaccard
  • Dice
  • Simpson

input data

user_id, item_id, rating
1, 2, 4
1, 127, 1
21, 63, 2
...

ex) http://files.grouplens.org/papers/ml-100k.zip

Example

http://files.grouplens.org/papers/ml-100k.zip

Download Data

$ cd gorec
$ sh ./scripts/download_data.sh

Calc simiralities

$ cd gorec
$ go run cmd/gorec/main.go ./data/ml-100k/u.data

Output

»»»» go run cmd/gorec/main.go ./data/ml-100k/u.data
2018/12/21 04:11:59 UserSize: 943
2018/12/21 04:11:59 ItemSize: 1682

+++User Simlarity+++

Adjusted Cosine
-----------------------------
2018/12/21 04:12:18 target ID: 941
rank    id       similarity
-----------------------------
 1       91      0.243949
 2       780     0.242358
-----------------------------
2018/12/21 04:12:18 target ID: 356
rank    id       similarity
-----------------------------
 1       101     0.462062
 2       518     0.446907
 3       181     0.430992
-----------------------------


+++Item Simlarity+++

Pearson
-----------------------------
2018/12/21 04:12:38 target ID: 941
rank    id       similarity
-----------------------------
 1       91      0.373956
 2       454     0.370661
-----------------------------
2018/12/21 04:12:38 target ID: 356
rank    id       similarity
-----------------------------
 1       518     0.480340
 2       181     0.477340
 3       101     0.496726
-----------------------------

Cosine
-----------------------------
2018/12/21 04:12:42 target ID: 941
rank    id       similarity
-----------------------------
 1       454     0.414486
 2       91      0.405048
-----------------------------
2018/12/21 04:12:42 target ID: 356
rank    id       similarity
-----------------------------
 1       101     0.516649
 2       181     0.510658
 3       518     0.501872
-----------------------------

change main.go

You can change some parameter for getting similar user/item.