包含將近3900部電影共1000209筆匿名評等 其中為2000年加入MovieLens 6040 MovieLens用戶的觀看資料。
movielens 1M data 共有3900部電影和6040的用戶的相關評分共計1000209筆 資料分為3部分:
I. ratings.dat
1. 資料格式: userID::movieID::rating::timestamp
2. rating為五級距
3. timestamp為自1970/1/1開始的秒數
4. 每個用戶都至少有20個評分(已經整理過，real data此點為需要克服的問題之一)
II. users.dat
1. 資料格式: userID::gender::age::occupation::zip-code
2. Gender 分為"M"男生和"F"女生
3. 年齡分為7個級距分別以該級距最小年齡作為紀錄，如下列
1: "Under 18"
18: "18-24"
25: "25-34"
35: "35-44"
45: "45-49"
50: "50-55"
56: "56+"
4. 職業共有21個類別，如下列
0: "other" or not specified
1: "academic/educator"
2: "artist"
3: "clerical/admin"
4: "college/grad student"
5: "customer service"
6: "doctor/health care"
7: "executive/managerial"
8: "farmer"
9: "homemaker"
10: "K-12 student"
11: "lawyer"
12: "programmer"
13: "retired"
14: "sales/marketing"
15: "scientist"
16: "self-employed"
17: "technician/engineer"
18: "tradesman/craftsman"
19: "unemployed"
20: "writer"
III. movies.dat
1. 資料格式: MovieID::Title::Genres
2. 共分成18個類別(參考IMDB)，一部電影可有多個類別用"|"隔開，如下列
Action
Adventure
Animation
Children's
Comedy
Crime
Documentary
Drama
Fantasy
Film-Noir
Horror
Musical
Mystery
Romance
Sci-Fi
Thriller
War
Western
3.電影資料為人工輸入，應進行基本防呆
參考來源: http://grouplens.org/datasets/movielens/1m/
目前建構方法: ALS-WR, user-based, movie association recommender
卡方值計算可參考: http://ocw.jhsph.edu/courses/fundepiii/pdfs/lecture17.pdf