Live data from Hacker News

Map Reduce: A simple introduction (2010)

ksat.me

1–10 of 37 posts

Re: Map Reduce: A simple introduction (2010)

#3

This is a fantastic explanation. anyone got any favourite uses of this / other resources to share of similar clarity?

I'm a big fan of (and occasional poster to) Reddit's Explain Like I'm Five, where you can ask questions and people are supposed to answer them in simple, accessible terms (if not in the "Little Timmy" literal 5yo sort of speech)

You can find it at http://www.reddit.com/r/explainlikeimfive

Re: Map Reduce: A simple introduction (2010)

#7

This is a fantastic explanation. anyone got any favourite uses of this / other resources to share of similar clarity?

I really like this one:

http://www.michaelnielsen.org/ddi/how-the-bitcoin-protocol-a...

He designs his own cryptocoin to explain the choices made by bitcoin and how it works.

Re: Map Reduce: A simple introduction (2010)

#8
Map Reduce seems very interesting, but every example I have seen explains it in terms of counting frequency of words in documents. I would love to have someone explain it with an actual business example. I can't think of many real world uses where counting the frequency of words would matter to most businesses. (besides maybe some analysis of log files)

Re: Map Reduce: A simple introduction (2010)

#9
post #8

Map Reduce seems very interesting, but every example I have seen explains it in terms of counting frequency of words in documents. I would love to have someone explain it with an actual business example. I can't think of many real world uses where counting the frequency of words would matter to most businesses. (besides maybe some analysis of log files)

The earliest search engines could be described as pretty much exactly this map-reduce.

Re: Map Reduce: A simple introduction (2010)

#10
post #8

Map Reduce seems very interesting, but every example I have seen explains it in terms of counting frequency of words in documents. I would love to have someone explain it with an actual business example. I can't think of many real world uses where counting the frequency of words would matter to most businesses. (besides maybe some analysis of log files)

Here's a tiny twist on WordCount that many, many companies use MR for (often their first foot in the water): you have many gigabytes or terabytes of web access logs and need to bill customers via some API scheme like /api/3001?x=1&y=2 where "3001" there is the customer ID. You add some regex and now you're doing "WordCount" on the customer ID (per day, month, etc).
Post reply on HN