Table 22 An overview of the proxies... | Emerald Publishing

Table 22

An overview of the proxies

Proxy	Allows statements related to the	Example
Reliability	Probability of not providing the expected level of service	The illustration of the average reliability of the bridges, tracks, earthworks and switches (0·995, 0·9525, 0·9987 and 0·9314 with strategy 1 and 0·999, 0·9768, 0·9997 and 0·9103 with strategy 2) gives an indication of how likely it is that a failure might happen. Figure 6 gives an indication that if strategy set 2 is followed, the railway network will be more reliable than if strategy set 1 is followed; however, it can be seen that this is not the case for objects of all types. There is, however, no information as to how much one should spend to remedy this or who is predominantly affected by this
Availability	Amount of time that railway objects are likely to not provide the expected level of service	The illustration of the average availability of the bridges, tracks, earthworks and switches (0·9997, 0·9990, 0·9946 and 0·9988 with strategy 1 and 0·9948, 0·9996, 0·9997 and 0·9994 with strategy 2) gives an indication of how long objects will be working as intended. It can be seen (Figure 7) that if strategy set 2 is followed, the railway objects will be providing the expected level of service for more time than if strategy set 1 is followed. There is, however, no information as to how much one should spend to remedy this or who is predominantly affected by this
Safety	Probability of users being injured or losing their lives	The illustration of the average probability of being injured or killed due to an accident on a bridge, track, earthwork and switch (0·9998, 0·9952, 0·9995 and 0·9931 with strategy 1 and 1·0000, 0·9977, 0·9999 and 0·9910 with strategy 2) enables one to see (Figure 8) that following strategy set 1 will result in far fewer injuries or fatalities than following strategy set 2. This allows discussion as to how much one should spend to prevent accidents. It does not, however, enable the full picture
State	The improvement or deterioration of the objects	The illustration of state gives an overall approximate view of whether or not the infrastructure is getting worse and the probability that it will fail (Figure 9). It also gives an idea of the amount of money one will need to spend in the future. It is, however, meaningful only if one compares it to an optimal trajectory of the state over time

Proxy	Allows statements related to the	Example
Reliability	Probability of not providing the expected level of service	The illustration of the average reliability of the bridges, tracks, earthworks and switches (0·995, 0·9525, 0·9987 and 0·9314 with strategy 1 and 0·999, 0·9768, 0·9997 and 0·9103 with strategy 2) gives an indication of how likely it is that a failure might happen. Figure 6 gives an indication that if strategy set 2 is followed, the railway network will be more reliable than if strategy set 1 is followed; however, it can be seen that this is not the case for objects of all types. There is, however, no information as to how much one should spend to remedy this or who is predominantly affected by this
Availability	Amount of time that railway objects are likely to not provide the expected level of service	The illustration of the average availability of the bridges, tracks, earthworks and switches (0·9997, 0·9990, 0·9946 and 0·9988 with strategy 1 and 0·9948, 0·9996, 0·9997 and 0·9994 with strategy 2) gives an indication of how long objects will be working as intended. It can be seen (Figure 7) that if strategy set 2 is followed, the railway objects will be providing the expected level of service for more time than if strategy set 1 is followed. There is, however, no information as to how much one should spend to remedy this or who is predominantly affected by this
Safety	Probability of users being injured or losing their lives	The illustration of the average probability of being injured or killed due to an accident on a bridge, track, earthwork and switch (0·9998, 0·9952, 0·9995 and 0·9931 with strategy 1 and 1·0000, 0·9977, 0·9999 and 0·9910 with strategy 2) enables one to see (Figure 8) that following strategy set 1 will result in far fewer injuries or fatalities than following strategy set 2. This allows discussion as to how much one should spend to prevent accidents. It does not, however, enable the full picture
State	The improvement or deterioration of the objects	The illustration of state gives an overall approximate view of whether or not the infrastructure is getting worse and the probability that it will fail (Figure 9). It also gives an idea of the amount of money one will need to spend in the future. It is, however, meaningful only if one compares it to an optimal trajectory of the state over time