Why so big difference among different compressor and platforms?

[GoogleCodeExporter]

two apks with elsim, results as following:
1 elsim.exe in windows
warning: compressor SNAPPY is not supported (use zlib default compressor)
Elements:
     IDENTICAL: 1408
     SIMILAR:   514
     NEW:       76
     DELETED:   1
     SKIPPED:   0
warning: compressor SNAPPY is not supported (use zlib default compressor)
    --> methods: 92.890752% of similarities

2 elsim in linux with snappy
Elements:
     IDENTICAL: 1408
     SIMILAR:   437
     NEW:       64
     DELETED:   78
     SKIPPED:   0
    --> methods: 91.919089% of similarities

3 elsim in linux with ZLIB
Elements:
     IDENTICAL: 1408
     SIMILAR:   484
     NEW:       40
     DELETED:   31
     SKIPPED:   0
    --> methods: 92.338823% of similarities

4 elsim in linux with BZ2
Elements:
     IDENTICAL: 1408
     SIMILAR:   502
     NEW:       43
     DELETED:   13
     SKIPPED:   0
    --> methods: 91.555399% of similarities

because the two apks are similar but one is obfuscated in code.
so seems the windows elsim.exe with zlib is a best result.

Why? Why 1 and 3 different since both use zlib? 

Original issue reported on code.google.com by lingtong...@gmail.com on 17 Jul 2013 at 4:38