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7.1 Example of the error definitions

Manual counting is assumed to be error-free.

Public Transport System:

Hagener Straßenbahn AG
(The vehicle was not empty when counting started.)

Comparative counting:

April 1, 1998

Vehicle:

O 405 GN, with 3 doors

 

Stops

manual counting

IRMA counting

Error (absolute value)

In

Out

In

Out

Out

Out

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47

2
2
24
4
2
3
8
2
0
0
1
0
0
3
0
1
3
1
0
0
1
0
0
7
0
13
25
4
3
3
11
1
0
0
1
4
2
0
0
1
1
4
4
1
0
2
3

1
4
29
2
4
0
11
6
0
0
4
2
3
6
0
2
2
14
2
0
0
4
1
5
2
8
7
9
2
0
7
2
0
0
0
0
0
0
0
2
4
0
0
0
0
0
1

2
2
21
5
2
1
8
2
0
0
1
0
0
1
0
0
3
1
0
0
1
0
0
7
0
13
26
4
3
4
12
1
0
0
2
2
1
0
0
1
1
3
4
1
0
2
3

1
5
27
2
4
0
11
6
0
0
4
2
2
7
0
2
2
13
2
0
0
4
1
4
1
8
6
11
2
0
7
2
0
0
0
0
0
0
0
2
3
0
0
0
0
0
1

0
0
3
1
0
2
0
0
0
0
0
0
0
2
0
1
0
0
0
0
0
0
0
0
0
0
1
0
0
1
1
0
0
0
1
2
1
0
0
0
0
1
0
0
0
0
0

0
1
2
0
0
0
0
0
0
0
0
0
1
1
0
0
0
1
0
0
0
0
0
1
1
0
1
2
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0

Total

147

146

140

142

17

12

In this example,

the passenger error is

=

(140 + 142) - (147 + 146)
–––––––––––––––––––––
147 + 146

x 100% = -4%,

 

 

 

 

the balanced boarding passenger error is

=

140 - 147
–––––––––––––––––––––
147

x 100% = -5%,

 

 

 

 

the balanced alighting passenger error is

=

142 - 146
–––––––––––––––––––––
146

x 100% = -3%,

 

 

 

 

the unbalanced error is

=

17 + 12
–––––––––––––––––––––
147 + 146

x 100% = 10%.


If no manually determined comparison figures are available for the evaluation of the counting accuracy, the mean deviation can be calculated.

the mean deviation

=

absolute value of the difference between boarding

and alighting passengers of automatic counting

at all stops and all doors of a vehicle

––––––––––––––––––––––––––––––––––––––––––
Sum of boarding passengers and alighting passengers

of automatic counting

at all stops and all doors of a vehicle


In this example,

is the mean deviation

=

ABS(140 - 142)
–––––––––––––––––––––
140 + 142

x 100% = 1%.