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Questions tagged [recommendation-engine]

For questions relating to recommendation engines, collaborative filtering, and personalization. Questions tend to be algorithmic or statistical in nature.

Recommendation engines are systems that suggest (recommend) to users various items for consideration. Some of the best known real world usage occurs at many major internet sites, such as Netflix, Amazon, Google, Yahoo, Pandora, last.fm, and others.

The input of such algorithms are most commonly the past purchases of the user, the rating the user gave to other goods, the items that have been purchased together ("customer who bought this also bought..."), the browsing history, etc.

For this tag, it is recommended that users focus on mathematical or statistical clarity, as it is a particularly advanced topic and implementation can take quite a bit of computational effort.

See also wikipedia.

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Python recommendation engine

Is there a recommendation engine for python similar to Java Taste?
StackUnderflow
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Building a Collaborative filtering / Recommendation System

I'm in the process of designing a website that is built around the concept of recommending various items to users based on their tastes. (i.e. items they've rated, items added to their favorites list, etc.) Some examples of this are Amazon,…
John
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Matrix factorization for collaborative filtering - new users and items?

I've been reading about using matrix factorization for collaborative filtering, but I can't seem to find an example that deals with adding a new user or item to the system, or having the user rate a new item. In these cases, the item-user matrix and…
pppnnn
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Recommendation algorithm (and implementation) for finding similar items and users

I have a database of about 700k users along with items they have watched/listened to/read/bought/etc. I would like to build a recommendation engine that recommends new items based on what users with similar taste in things have enjoyed, as well as…
vomitcuddle
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Recommendation engine in Rails

I would like to have a recommendation functionality for my Rails web app. In particular, I want to recommend a newly signed-up user other users he may want to follow. Is there an engine/gem for this purpose in Rails? If not, where should I start to…
AdamNYC
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ImportError: cannot import name 'evaluate' ( from surprise import evaluate )

from surprise import Reader, Dataset, SVD from surprise import evaluate --------------------------------------------------------------------------- ImportError Traceback (most recent call…
Tushar
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Recommendation system with matrix factorization for huge data gives MemoryError

I have three DB models (from Django) that can be used as the input for building a recommendation system: Users List - with userId, username, email etc Movies List - with movieId, movieTitle, Topics etc Saves List - with userId, movieId and…
Vlad
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How do I optimize the hyperparameters of LightFM?

I am using the LightFM recommender library on my dataset, which gives me the results in the image below. NUM_THREADS = 4 NUM_COMPONENTS = 30 NUM_EPOCHS = 5 ITEM_ALPHA = 1e-6 LEARNING_RATE = 0.005 LEARNING_SCHEDULE = 'adagrad' RANDOM_SEED = 29031994…
Tim Visser
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Pearson correlation fails for perfectly correlated sets

Consider the following examples of the Pearson correlation coefficient on sets of film ratings by users A and B: A = [2,4,4,4,4] B = [5,4,4,4,4] pearson(A,B) = -1 A = [5,5,5,5,5] B = [5,5,5,5,5] pearson(A,B) = NaN Pearson correlation seems widely…
Cam Price-Austin
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"ValueError: labels ['timestamp'] not contained in axis" error

I have this code ,i want to remove the column 'timestamp' from the file :u.data but can't.It shows the error "ValueError: labels ['timestamp'] not contained in axis" How can i correct it import numpy as np import pandas as pd import…
avaj
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ORM mapper for windows 7 phone

I thinking of using SQLite with win7 phone for development of my app. I looking for an ORM mapper which will work with Windows 7 phone and SQLite.
Gainster
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How to improve my recommendation result? I am using spark ALS implicit

First, I have some use history of user's app. For example: user1, app1, 3(launch times) user2, app2, 2(launch times) user3, app1, 1(launch times) I have basically two demands: Recommend some app for every user. Recommend similar app for every…
yyforever1988
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Why rank-based recommendation use NDCG?

rank-based recommendation system use NDCG to evaluate Recommendation accuracy. However, sometimes Accuracy rate and recall rate are used to evaluate top-n recommendation. Does it mean when NDCG is high, accuracy rate is high? But I run a ListRankMF…
Try Leung
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Apache Spark ALS recommendations approach

Trying to build recommendation system using Spark MLLib's ALS. Currently, we're trying to pre-build recommendations for all users on daily basis. We're using simple implicit feedbacks and ALS. The problem is, we have 20M users and 30M products, and…
Aram Mkrtchyan
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Solr MoreLikeThis boosting query fields

I am experimenting with Solr's MoreLikeThis feature. My schema deals with articles, and I'm looking for similarities between articles within three fields: articletitle, articletext and topic. The following query works…
JBradshaw
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