1118856Sphk$FreeBSD$
2118856Sphk
3118856SphkA small tool to do the statistics legwork on benchmarks etc.
4118856Sphk
5118856SphkPrepare your data into two files, one number per line
6118856Sphkrun 
7118856Sphk	./ministat data_before data_after
8118856Sphk
9118856Sphkand see what it says.
10118856Sphk
11118856SphkYou need at least three data points in each data set, but the more
12118856Sphkyou have the better your result generally gets.
13118856Sphk
14118856SphkHere are two typical outputs:
15118856Sphk
16118856Sphkx _1
17118856Sphk+ _2
18118856Sphk+--------------------------------------------------------------------------+
19118856Sphk|x            +    x+      x            x   x             +           ++   |
20118856Sphk|        |_________|______AM_______________|__A___________M_______________||
21118856Sphk+--------------------------------------------------------------------------+
22118856Sphk    N           Min           Max        Median           Avg        Stddev
23118856Sphkx   5         36060         36138         36107       36105.6     31.165686
24118856Sphk+   5         36084         36187         36163       36142.6     49.952978
25118856SphkNo difference proven at 95.0% confidence
26118856Sphk
27118856SphkHere nothing can be concluded from the numbers.  It _may_ be possible to
28118856Sphkprove something if many more measurements are made, but with only five
29118856Sphkmeasurements, nothing is proven.
30118856Sphk
31118856Sphk
32118856Sphkx _1
33118856Sphk+ _2
34118856Sphk+--------------------------------------------------------------------------+
35118856Sphk|                                                               +          |
36118856Sphk|                               x                               +         +|
37118856Sphk|x                    x         x          x                    +         +|
38118856Sphk|         |_______________A_____M_________|                   |_M___A____| |
39118856Sphk+--------------------------------------------------------------------------+
40118856Sphk    N           Min           Max        Median           Avg        Stddev
41118856Sphkx   5         0.133         0.137         0.136        0.1354  0.0015165751
42118856Sphk+   5         0.139          0.14         0.139        0.1394 0.00054772256
43118856SphkDifference at 95.0% confidence
44118856Sphk        0.004 +/- 0.00166288
45118856Sphk        2.95421% +/- 1.22812%
46118856Sphk        (Student's t, pooled s = 0.00114018)
47118856Sphk
48118856SphkHere we have a clearcut difference, not very big, but clear and unambiguous.
49118856Sphk
50118856Sphk
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