8 ms·

Introduction to Recommender Systems

194 points by swGooF 13y ago

ghc 13y ago
I can't judge the coursera course, but for anyone who is interested in this field and wants a gentle introduction, I high recommend Programming Collective Intelligence (http://shop.oreilly.com/product/9780596529321.do http://shop.oreilly.com/product/9780596529321.do). It covers many of the types of recommender systems that the coursera course is likely to cover, and comes with a lot of nice Python code examples. It's highly useful knowledge too. I ran across so many startups that needed recommender systems that I launched a company called Algorithmic.ly (http://algorithmic.ly http://algorithmic.ly) to help companies without the expertise integrate recommendation systems and other types of algorithms into their projects.
- riggins 13y ago
  Thanks for the recommendation.
  - phektus 13y ago
    Meta. Sorry :P
- dougk7 13y ago
  PCI is a great book. One book I'll recommend after reading it is "Mining of Massive Datasets" (http://infolab.stanford.edu/~ullman/mmds.html http://infolab.stanford.edu/~ullman/mmds.html) - Chapter 9 especially. It goes into more depth than what's covered in PCI and it's not too difficult to follow. I'm working on a personal project in recommender systems so I look forward to enjoy this course.
  - kops 13y ago
    Thanks for that link. Chapter 7 helped answer some of the questions I had after reading PCI.
- arms 13y ago
  I was about to buy PCI a few days ago, but was worried that the information may be out of date, considering it was published six years ago. Do you think most of the material is still pertinent?
  - ghc 13y ago
    I believe all of the material is still pertinent. It primarily uses the MovieLens data set and mostly builds off of textbook techniques and generic Python. It's not a book that will go out of data quickly.
  - kops 13y ago
    Go for it. It's a great book and except for references to friendster as the big social network and facebook a newbie, nothing else seemed dated to me. Most of the APIs used in the book are still pretty much available except probably(??) delicious API.
  - clinth 13y ago
    I was a technical reviewer of that book (although no knowledge of PCI in practice), and I found it to be less moment-specific and more general grounding and strategy than I expected. It really is a good book.
  - arms 13y ago
    Thanks for the recommendations, all. Just got my copy delivered yesterday and I'm looking forward to digging into it.
- tungwaiyip 13y ago
  In this short article I have implemented the algorithm in the Programming Collective Intelligence in 9 lines of code http://tungwaiyip.info/2012/Collaborative%20Filtering.html http://tungwaiyip.info/2012/Collaborative%20Filtering.html
eldog_ 13y ago
I'd be interested in knowing how much deep learning is changing the algorithms used in this field, given the performance of restricted boltzmann machines on the netflix data set http://www.cs.utoronto.ca/~hinton/absps/netflixICML.pdf http://www.cs.utoronto.ca/~hinton/absps/netflixICML.pdf.
- colincsl 13y ago
  I am surprised that there is no mention of this in the course syllabus -- in fact it looks like a lot of recent techniques that are missing. They don't even talking about LSA(/SVD)-based methods until the end of the course.
  - jere 13y ago
    Dumb, general question: should it really be a surprise that an Introduction course doesn't use all the recent techniques?
    - colincsl 13y ago
      I guess I often assume that topics classes like these assume some sort of background in machine learning. Perhaps that's not the case.
    - textminer 13y ago
      LSA and truncated SVDs on a user-item matrix date back to the 1980s, don't they?
- elq 13y ago
  You'd be surprised how overwhelmingly common and effective very simple methods like logistic regression and basic decision trees are for such systems. Further, RBMs and other deep learning tools require a significantly more sophisticated mathematical background than algebra and a much broader understanding overall.
- Irishsteve 13y ago
  The netflix prize touched on one of many areas related to recommender systems. As mentioned already, very simple methods can be really effective. Things such as the UI are also known to have a big impact on how 'useful' people find the recs.
riggins 13y ago
coursera is killing me with courses I want to take.
- DannoHung 13y ago
  I just wish you could take the classes at your own pace. I'm getting very little out of the "certifications" or whatever. And the TA's/Discussion forums tend towards pretty useless because of how disorganized they are.
  - srom 13y ago
    Download the resources and you'll be able to take the class at your own pace. There are several tools for that purpose on github. e.g this one: https://github.com/dgorissen/coursera-dl https://github.com/dgorissen/coursera-dl As a special gift, it's allow you to archive the courses for later review.
    - dombili 13y ago
      Another note: If you can't make that tool work (I know I couldn't), you can also use something like DownloadThemAll. It works great.
    - DannoHung 13y ago
      Mainly I just want the graders to stay up. I've taken 2 programming courses and having the auto-grader feedback really helps in figuring out how I'm doing assignments incorrectly.
      - pallandt 13y ago
        I think the main reason why any reasonably complex grader is not allowed to run after the course has officially finalized is cost(s). While for users it's free to take the course, the offering company probably has to pay fees to whatever IaaS they're using to run the grader(s). I would imagine to make it 'cost-effective' for their purposes, they'd be interested in as many people as possible benefiting from the grader's functionality if they're being charged by the hour for example or some other block-allocation unit. I would suggest giving Udacity a try as well. Most of their courses do not have deadlines. For example, here is a great course they offer on web development: https://www.udacity.com/course/cs253 https://www.udacity.com/course/cs253 , co-authored by one of the Hipmunk and Reddit creators.
victorhooi 13y ago
Hmm, seems interesting = I'm currently doing the Machine Learning one also via Coursera, run by Andrew Ng, and it's good gentle introduction to the subject. It's a shame we can't view the course content for this one earlier...haha.
- pallandt 13y ago
  I may be wrong, but I think it's the 1st time the course is being offered, I don't personally remember seeing it before in their course list.
  - cgag 13y ago
    I think that was one of the first courses they offered actually.
    - pallandt 13y ago
      I think you're probably confusing it with something similarly named. See http://www.cs.umn.edu/news/news.php?id=1293 http://www.cs.umn.edu/news/news.php?id=1293 which confirms it's being offered for the 1st time.
mark_l_watson 13y ago
If you want a quick start without taking a class, install the Apache Mahout project - one of the Hadoop map-reduce examples is a recommendation system. You can hack away, and run on Elastic MapReduce if you need to scale. (https://cwiki.apache.org/confluence/display/MAHOUT/Recommender+Documentation https://cwiki.apache.org/confluence/display/MAHOUT/Recommend...)
axansh 13y ago
Thanks coursera. Thank you very much. Looking forward for this course. You save my some $$$ :) Will surely donate you.
oneeyedpigeon 13y ago
I couldn't possibly recommend a site that requires javascript to display any content whatsoever.
- jwr 13y ago
  Why not? JavaScript has become a part of the web, just as much as HTML and CSS. You might as well shun sites that use the <ul> tag, or CSS to style content.
  - oneeyedpigeon 13y ago
    JavaScript should certainly be used to enhance content and ad functionality. But the core content should always be available without JS, since not all consumers of that content will have JS enabled, or be able to interpret it.
- Ntrails 13y ago
  <div style="text-align:center; margin-bottom:10px;">Please use a <a href="/browsers">modern browser </a> with JavaScript enabled to use Coursera.</div> Good job there folks
- rypskar 13y ago
  At least they use noscript and give you a warning if you don’t have javascript enabled, there are so many sites that don’t check if javascript and cookies are enabled
arek2 13y ago
I'll drop a link to my (non-free) e-book: http://arek-paterek.com/book/ http://arek-paterek.com/book/
javindo 13y ago
Interesting anecdote: A graduate of my university works for Google who originally had a very complex "machine learning pipeline" for the product recommendations but he has since re-implemented the feature in, as he calls it, a "much simpler bloom filter algorithm".
fmela 13y ago
So many great online courses, and so little time!

194 points by swGooF 13y ago

ghc 13y ago

I can't judge the coursera course, but for anyone who is interested in this field and wants a gentle introduction, I high recommend Programming Collective Intelligence (http://shop.oreilly.com/product/9780596529321.do http://shop.oreilly.com/product/9780596529321.do). It covers many of the types of recommender systems that the coursera course is likely to cover, and comes with a lot of nice Python code examples. It's highly useful knowledge too. I ran across so many startups that needed recommender systems that I launched a company called Algorithmic.ly (http://algorithmic.ly http://algorithmic.ly) to help companies without the expertise integrate recommendation systems and other types of algorithms into their projects.

riggins 13y ago
Thanks for the recommendation.
- phektus 13y ago
  Meta. Sorry :P
dougk7 13y ago
PCI is a great book. One book I'll recommend after reading it is "Mining of Massive Datasets" (http://infolab.stanford.edu/~ullman/mmds.html http://infolab.stanford.edu/~ullman/mmds.html) - Chapter 9 especially. It goes into more depth than what's covered in PCI and it's not too difficult to follow. I'm working on a personal project in recommender systems so I look forward to enjoy this course.
- kops 13y ago
  Thanks for that link. Chapter 7 helped answer some of the questions I had after reading PCI.
arms 13y ago
I was about to buy PCI a few days ago, but was worried that the information may be out of date, considering it was published six years ago. Do you think most of the material is still pertinent?
- ghc 13y ago
  I believe all of the material is still pertinent. It primarily uses the MovieLens data set and mostly builds off of textbook techniques and generic Python. It's not a book that will go out of data quickly.
- kops 13y ago
  Go for it. It's a great book and except for references to friendster as the big social network and facebook a newbie, nothing else seemed dated to me. Most of the APIs used in the book are still pretty much available except probably(??) delicious API.
- clinth 13y ago
  I was a technical reviewer of that book (although no knowledge of PCI in practice), and I found it to be less moment-specific and more general grounding and strategy than I expected. It really is a good book.
- arms 13y ago
  Thanks for the recommendations, all. Just got my copy delivered yesterday and I'm looking forward to digging into it.
tungwaiyip 13y ago
In this short article I have implemented the algorithm in the Programming Collective Intelligence in 9 lines of code http://tungwaiyip.info/2012/Collaborative%20Filtering.html http://tungwaiyip.info/2012/Collaborative%20Filtering.html

eldog_ 13y ago

I'd be interested in knowing how much deep learning is changing the algorithms used in this field, given the performance of restricted boltzmann machines on the netflix data set http://www.cs.utoronto.ca/~hinton/absps/netflixICML.pdf http://www.cs.utoronto.ca/~hinton/absps/netflixICML.pdf.

colincsl 13y ago
I am surprised that there is no mention of this in the course syllabus -- in fact it looks like a lot of recent techniques that are missing. They don't even talking about LSA(/SVD)-based methods until the end of the course.
- jere 13y ago
  Dumb, general question: should it really be a surprise that an Introduction course doesn't use all the recent techniques?
  - colincsl 13y ago
    I guess I often assume that topics classes like these assume some sort of background in machine learning. Perhaps that's not the case.
  - textminer 13y ago
    LSA and truncated SVDs on a user-item matrix date back to the 1980s, don't they?
elq 13y ago
You'd be surprised how overwhelmingly common and effective very simple methods like logistic regression and basic decision trees are for such systems. Further, RBMs and other deep learning tools require a significantly more sophisticated mathematical background than algebra and a much broader understanding overall.
Irishsteve 13y ago
The netflix prize touched on one of many areas related to recommender systems. As mentioned already, very simple methods can be really effective. Things such as the UI are also known to have a big impact on how 'useful' people find the recs.

riggins 13y ago

coursera is killing me with courses I want to take.

DannoHung 13y ago
I just wish you could take the classes at your own pace. I'm getting very little out of the "certifications" or whatever. And the TA's/Discussion forums tend towards pretty useless because of how disorganized they are.
- srom 13y ago
  Download the resources and you'll be able to take the class at your own pace. There are several tools for that purpose on github. e.g this one: https://github.com/dgorissen/coursera-dl https://github.com/dgorissen/coursera-dl As a special gift, it's allow you to archive the courses for later review.
  - dombili 13y ago
    Another note: If you can't make that tool work (I know I couldn't), you can also use something like DownloadThemAll. It works great.
  - DannoHung 13y ago
    Mainly I just want the graders to stay up. I've taken 2 programming courses and having the auto-grader feedback really helps in figuring out how I'm doing assignments incorrectly.
    - pallandt 13y ago
      I think the main reason why any reasonably complex grader is not allowed to run after the course has officially finalized is cost(s). While for users it's free to take the course, the offering company probably has to pay fees to whatever IaaS they're using to run the grader(s). I would imagine to make it 'cost-effective' for their purposes, they'd be interested in as many people as possible benefiting from the grader's functionality if they're being charged by the hour for example or some other block-allocation unit. I would suggest giving Udacity a try as well. Most of their courses do not have deadlines. For example, here is a great course they offer on web development: https://www.udacity.com/course/cs253 https://www.udacity.com/course/cs253 , co-authored by one of the Hipmunk and Reddit creators.

victorhooi 13y ago

Hmm, seems interesting = I'm currently doing the Machine Learning one also via Coursera, run by Andrew Ng, and it's good gentle introduction to the subject. It's a shame we can't view the course content for this one earlier...haha.

pallandt 13y ago
I may be wrong, but I think it's the 1st time the course is being offered, I don't personally remember seeing it before in their course list.
- cgag 13y ago
  I think that was one of the first courses they offered actually.
  - pallandt 13y ago
    I think you're probably confusing it with something similarly named. See http://www.cs.umn.edu/news/news.php?id=1293 http://www.cs.umn.edu/news/news.php?id=1293 which confirms it's being offered for the 1st time.

mark_l_watson 13y ago

If you want a quick start without taking a class, install the Apache Mahout project - one of the Hadoop map-reduce examples is a recommendation system. You can hack away, and run on Elastic MapReduce if you need to scale. (https://cwiki.apache.org/confluence/display/MAHOUT/Recommender+Documentation https://cwiki.apache.org/confluence/display/MAHOUT/Recommend...)

axansh 13y ago

Thanks coursera. Thank you very much. Looking forward for this course. You save my some $$$ :) Will surely donate you.

oneeyedpigeon 13y ago

I couldn't possibly recommend a site that requires javascript to display any content whatsoever.

jwr 13y ago
Why not? JavaScript has become a part of the web, just as much as HTML and CSS. You might as well shun sites that use the <ul> tag, or CSS to style content.
- oneeyedpigeon 13y ago
  JavaScript should certainly be used to enhance content and ad functionality. But the core content should always be available without JS, since not all consumers of that content will have JS enabled, or be able to interpret it.
Ntrails 13y ago
<div style="text-align:center; margin-bottom:10px;">Please use a <a href="/browsers">modern browser </a> with JavaScript enabled to use Coursera.</div> Good job there folks
rypskar 13y ago
At least they use noscript and give you a warning if you don’t have javascript enabled, there are so many sites that don’t check if javascript and cookies are enabled

arek2 13y ago

I'll drop a link to my (non-free) e-book: http://arek-paterek.com/book/ http://arek-paterek.com/book/

javindo 13y ago

Interesting anecdote: A graduate of my university works for Google who originally had a very complex "machine learning pipeline" for the product recommendations but he has since re-implemented the feature in, as he calls it, a "much simpler bloom filter algorithm".

fmela 13y ago

So many great online courses, and so little time!