computer failure data, STAT 554

Computer Failure Data

The values below are the numbers of times a DEC-20 computer at Open University broke down in each of 128 consecutive weeks of operation, starting in late 1983.

4
0
0
0
3
2
0
0
6
7
6
2
1
11
6
1
2
1
1
2
0
2
2
1
0
12
8
4
5
0
5
4
1
0
8
2
5
2
1
12
8
9
10
17
2
3
4
8
1
2
5
1
2
2
3
1
2
0
2
1
6
3
3
6
11
10
4
3
0
2
4
2
1
5
3
3
2
5
3
4
1
3
6
4
4
5
2
10
4
1
5
6
9
7
3
1
3
0
2
2
1
4
2
13
0
2
1
1
0
3
16
22
5
1
2
4
7
8
6
11
3
0
4
7
8
4
4
5