title: What is the formula to calculate parallel efficiency of map reduce algorithm?
body: <p>Is there any formula which can tell us parallel efficiency of map reduce algorithm? (in other words how I can mathematically prove that MR algorithm A is better than MR algorithm B)</p>
  
  <p>I googled it but I could find just the definition of speed-up and efficiency for parallel algorithms on <a href="http://en.wikipedia.org/wiki/Speedup" rel="nofollow">wiki</a> but it will be good if someone can show how those formulas are applied to MR algorithms</p>