MRT improved: Meaningless statistics?

By: Leong Sze Hian

Reliability of MRT lines improves

I refer to the article “Reliability of North-South and Circle MRT Lines improves; East-West Line maintains same standard” (Straits Times, Apr 24).

It states that “In the year ending Q1, the NSL clocked an average of 180,000km before a delay lasting more than 5 mins, bettering the 156,000km registered in the year ending Q4, 2016.”

According to the article “MRT network performance up 30 per cent in 2016 from 2015” (Straits Times, Jan 12) –

Trains travelled longer distances before delays?

“last year, trains clocked 174,000 train-km travelled between delays of more than five minutes, a 30 per cent increase from 133,000 train-km in 2015.”

Last year’s was 174,000 or 156,000 km? 

So, how is it that “last year, trains clocked 174,000 train-km travelled between delays of more than five minutes” has now been apparently become “before a delay lasting more than 5 mins, bettering the 156,000 km registered in the year ending Q4, 2016”?

So, is it 174,000 or 156,000 km travelled between delays of more than five minutes, in the last year?

As to “The EWL, however, maintained the same level of Mean Kilometre Between Failure (MKBF) – a key measurement of reliability -of 145,000 km for both periods.

The CCL improved its MKBF to 282,000km from 228,000km previously” –

Who cares how many km travelled between delays?

arguably, what commuters may be more irked by – may not be how many km were travelled between (before the next delay) delays of more than five minutes, but rather how many delays of more than five minutes there were and whether these have increased.

How many longer delays?

What is perhaps even more important from the perspective of commuters may be how many delays there were of more than 10, 15, 30 minutes, one hour, etc – and whether these have increased?

Analogy?

As an analogy – it may be akin to telling you that you walked longer before you got hit by the next accident, but without telling you how serious the accidents were, or whether the number of accidents has increased?

Less meaningful statistics?

This may in a sense be somewhat like telling you the statistics that has less meaning or arguably, no meaning at all to you.