b-a の分布
---------
-8.0, 0,
-7.5, 0,
-7.0, 4,
-6.5, 2,
-6.0, 0,
-5.5, 2,
-5.0, 6,
-4.5, 14,
-4.0, 12,
-3.5, 13,
-3.0, 9,
-2.5, 18,
-2.0, 24,
-1.5, 32,
-1.0, 35,
-0.5, 27,
0.0, 22,
0.5, 27,
1.0, 40,
1.5, 58,
---------------
2.0, 39,
2.5, 30,
3.0, 19,
3.5, 27,
4.0, 30,
4.5, 32,
5.0, 28,
5.5, 20,
6.0, 11,
6.5, 10,
7.0, 9,
7.5, 12,
8.0, 4,
8.5, 4,
9.0, 0,
9.5, 2,
10.0, 2,
10.5, 0,
11.0, 0,
----------
計, 624,
標本平均Average, 1.43108975,
標本分散, 10.52329625,
標本標準偏差, 3.24396305,
最頻値mode, 1.5,
中央値median, 1.5