row.names	gruppe	mittel	verlaen
1	a	1	-0.3
2	a	2	 1.4
3	a	3	 0.7
4	a	4	 2.7
5	b	1	 0.5
6	b	2	 1.1
7	b	3	-0.2
8	b	4	 0.8
9	c	1	 1.3
10	c	2	-0.1
11	c	3	-0.4
12	c	4	 1.9
13	d	1	-0.5
14	d	2	 0.7
15	d	3	 1.0
16	d	4	 3.1
17	e	1	 0.6
18	e	2	 1.1
19	e	3	-0.1
20	e	4	 0.5