Some examples of MapReduce applications

Here are a few examples of big data problems that can be solved with the MapReduce framework:

1. Given a repository of text files, find the frequency of each word. This is called the WordCount problem.

2. Given a repository of text files, find the number of words of each word length.

3. Given two matrices in sparse matrix format, compute their product.

4. Factor a matrix given in sparse matrix format.

5. Given a symmetric graph whose nodes represent people and edges represent friendship, compile a list of common friends.

6. Given a symmetric graph whose nodes represent people and edges represent friendship, compute the average number of friends by age.

7. Given a repository of weather records, find the annual global minima and maxima by year.

8. Sort a large list. Note that in most implementations of the MapReduce framework, this problem is trivial, because the framework automatically sorts the output from the map() function.

9. Reverse a graph.

10. Find a minimal spanning tree (MST) of a...