Tag Archives: Stable system of trouble

UK railway suicides – 2014 update

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It’s taken me a while to sit down and blog about this news item from October 2014: Sharp Rise in Railway Suicides Say Network Rail . Regular readers of this blog will know that I have followed this data series closely in 2013 and 2012.

The headline was based on the latest UK government data. However, I baulk at the way these things are reported by the press. The news item states as follows.

The number of people who have committed suicide on Britain’s railways in the last year has almost reached 300, Network Rail and the Samaritans have warned. Official figures for 2013-14 show there have already been 279 suicides on the UK’s rail network – the highest number on record and up from 246 in the previous year.

I don’t think it’s helpful to characterise 279 deaths as “almost … 300”, where there is, in any event, no particular significance in the number 300. It arbitrarily conveys the impression that some pivotal threshold is threatened. Further, there is no especial significance in an increase from 246 to 279 deaths. Another executive time series. Every one of the 279 is a tragedy as is every one of the 246. The experience base has varied from year to year and there is no surprise that it has varied again. To assess the tone of the news report I have replotted the data myself.

RailwaySuicides3

Readers should note the following about the chart.

  • Some of the numbers for earlier years have been updated by the statistical authority.
  • I have recalculated natural process limits as there are still no more than 20 annual observations.
  • There is now a signal (in red) of an observation above the upper natural process limit.

The news report is justified, unlike the earlier ones. There is a signal in the chart and an objective basis for concluding that there is more than just a stable system of trouble. There is a signal and not just noise.

As my colleague Terry Weight always taught me, a signal gives us license to interpret the ups and downs on the chart. There are two possible narratives that immediately suggest themselves from the chart.

  • A sudden increase in deaths in 2013/14; or
  • A gradual increasing trend from around 200 in 2001/02.

The chart supports either story. To distinguish would require other sources of information, possibly historical data that can provide some borrowing strength, or a plan for future data collection. Once there is a signal, it makes sense to ask what was its cause. Building  a narrative around the data is a critical part of that enquiry. A manager needs to seek the cause of the signal so that he or she can take action to improve system outcomes. Reliably identifying a cause requires trenchant criticism of historical data.

My first thought here was to wonder whether the railway data simply reflected an increasing trend in suicide in general. Certainly a very quick look at the data here suggests that the broader trend of suicides has been downwards and certainly not increasing. It appears that there is some factor localised to railways at work.

I have seen proposals to repeat a strategy from Japan of bathing railway platforms with blue light. I have not scrutinised the Japanese data but the claims made in this paper and this are impressive in terms of purported incident reduction. If these modifications are implemented at British stations we can look at the chart to see whether there is a signal of fewer suicides. That is the only real evidence that counts.

Those who were advocating a narrative of increasing railway suicides in earlier years may feel vindicated. However, until this latest evidence there was no signal on the chart. There is always competition for resources and directing effort on a false assumptions leads to misallocation. Intervening in a stable system of trouble, a system featuring only noise, on the false belief that there is a signal will usually make the situation worse. Failing to listen to the voice of the process on the chart risks diverting vital resources and using them to make outcomes worse.

Of course, data in terms of time between incidents is much more powerful in spotting an early signal. I have not had the opportunity to look at such data but it would have provided more, better and earlier evidence.

Where there is a perception of a trend there will always be an instinctive temptation to fit a straight line through the data. I always ask myself why this should help in identifying the causes of the signal. In terms of analysis at this stage I cannot see how it would help. However, when we come to look for a signal of improvement in future years it may well be a helpful step.

Deconstructing Deming X – Eliminate slogans!

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10. Eliminate slogans, exhortations and targets for the workforce.

W Edwards Deming

Neither snow nor rain nor heat nor gloom of night stays these couriers from the swift completion of their appointed rounds.

Inscription on the James Farley Post Office, New York City, New York, USA
William Mitchell Kendall pace Herodotus

Now, that’s what I call a slogan. Is this what Point 10 of Deming’s 14 Points was condemning? There are three heads here, all making quite distinct criticisms of modern management. The important dimension of this criticism is the way in which managers use data in communicating with the wider organisation, in setting imperatives and priorities and in determining what individual workers will consider important when they are free from immediate supervision.

Eliminate slogans!

The US postal inscription at the head of this blog certainly falls within the category of slogans. Apparently the root of the word “slogan” is the Scottish Gaelic sluagh-ghairm meaning a battle cry. It seeks to articulate a solidarity and commitment to purpose that transcends individual doubts or rationalisation. That is what the US postal inscription seeks to do. Beyond the data on customer satisfaction, the demands of the business to protect and promote its reputation, the service levels in place for individual value streams, the tension between current performance and aspiration, the disappointment of missed objectives, it seeks to draw together the whole of the organisation around an ideal.

Slogans are part of the broader oral culture of an organisation. In the words of Lawrence Freedman (Strategy: A History, Oxford, 2013, p564) stories, and I think by extension slogans:

[make] it possible to avoid abstractions, reduce complexity, and make vital points indirectly, stressing the importance of being alert to serendipitous opportunities, discontented staff, or the one small point that might ruin an otherwise brilliant campaign.

But Freedman was quick to point out the use of stories by consultants and in organisations frequently confused anecdote with data. They were commonly used selectively and often contrived. Freedman sought to extract some residual value from the culture of business stories, in particular drawing on the work of psychologist Jerome Bruner along with Daniel Kahneman’s System 1 and System 2 thinking. The purpose of the narrative of an organisation, including its slogans and shared stories, is not to predict events but to define a context for action when reality is inevitably overtaken by a special cause.

In building such a rich narrative, slogans alone are an inert and lifeless tactic unless woven with the continual, rigorous criticism of historical data. In fact, it is the process behaviour chart that acts as the armature around which the narrative can be wound. Building the narrative will be critical to how individuals respond to the messages of the chart.

Deming himself coined plenty of slogans: “Drive out fear”, “Create joy in work”, … . They are not forbidden. But to be effective they must form a verisimilar commentary on, and motivation for, the hard numbers and ineluctable signals of the process behaviour chart.

Eliminate exhortations!

I had thought I would dismiss this in a single clause. It is, though, a little more complicated. The sports team captain who urges her teammates onwards to take the last gasp scoring opportunity doesn’t necessarily urge in vain. There is no analysis of this scenario. It is only muscle, nerve, sweat and emotion.

The English team just suffered a humiliating exit from the Cricket World Cup. The head coach’s response was “We’ll have to look at the data.” Andrew Miller in The Times (London) (10 March 2015) reflected most cricket fans’ view when he observed that “a team of meticulously prepared cricketers suffered a collective loss of nerve and confidence.” Exhortations might not have gone amiss.

It is not, though, a management strategy. If your principal means of managing risk, achieving compelling objectives, creating value and consistently delivering customer excellence, day in, day out is to yell “one more heave!” then you had better not lose your voice. In the long run, I am on the side of the analysts.

Slogans and exhortations will prove a brittle veneer on a stable system of trouble (RearView). It is there that they will inevitably corrode engagement, breed cynicism, foster distrust, and mask decline. Only the process behaviour chart can guard against the risk.

Eliminate targets for the workforce!

This one is more complicated. How do I communicate to the rest of the organisation what I need from them? What are the consequences when they don’t deliver? How do the rest of the organisation communicate with me? This really breaks down into two separate topics and they happen to be the two halves of Deming’s Point 11.

I shall return to those in my next two posts in the Deconstructing Deming series.

 

Deconstructing Deming III – Cease reliance on inspection

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3. Cease dependence on inspection to achieve quality. Eliminate the need for massive inspection by building quality into the product in the first place.

W Edwards Deming Point 3 of Deming’s 14 Points. This at least cannot be controversial. For me it goes to the heart of Deming’s thinking.

The point is that every defective item produced (or defective service delivered) has taken cash from the pockets of customers or shareholders. They should be more angry. One day they will be. Inputs have been purchased with their cash, their resources have been deployed to transform the inputs and they will get nothing back in return. They will even face the costs of disposing of the scrap, especially if it is environmentally noxious.

That you have an efficient system for segregating non-conforming from conforming is unimpressive. That you spend even more of other people’s money reworking the product ought to be a matter of shame. Lean Six Sigma practitioners often talk of the hidden factory where the rework takes place. A factory hidden out of embarrassment. The costs remain whether you recognise them or not. Segregation is still more problematic in service industries.

The insight is not unique to Deming. This is a common theme in Lean, Six Sigma, Theory of Constraints and other approaches to operational excellence. However, Deming elucidated the profound statistical truths that belie the superficial effectiveness of inspection.

Inspection is inefficient

When I used to work in the railway industry I was once asked to look at what percentage of signalling scheme designs needed to be rechecked to defend against the danger of a logical error creeping through. The problem requires a simple application of Bayes’ theorem. I was rather taken aback at the result. There were only two strategies that made sense: recheck everything or recheck nothing. I didn’t at that point realise that this is a standard statistical result in inspection theory. For a wide class of real world situations, where the objective is to segregate non-conforming from conforming, the only sensible sampling schemes are 100% or 0%.

Where the inspection technique is destructive, such as a weld strength test, there really is only one option.

Inspection is ineffective

All inspection methods are imperfect. There will be false-positives and false-negatives. You will spend some money scrapping product you could have sold for cash. Some defective product will escape onto the market. Can you think of any examples in your own experience? Further, some of the conforming product will be only marginally conforming. It won’t delight the customer.

So build quality into the product

… and the process for producing the product (or delivering the service). Deming was a champion of the engineering philosophy of Genechi Taguchi who put forward a three-stage approach for achieving, what he called, off-line quality control.

  1. System design – in developing a product (or process) concept think about how variation in inputs and environment will affect performance. Choose concepts that are robust against sources of variation that are difficult or costly to control.
  2. Parameter design – choose product dimensions and process settings that minimise the sensitivity of performance to variation.
  3. Tolerance design – work out the residual sources of variation to which performance remains sensitive. Develop control plans for measuring, managing and continually reducing such variation.

Is there now no need to measure?

Conventional inspection aimed at approving or condemning a completed batch of output. The only thing of interest was the product and whether it conformed. Action would be taken on the batch. Deming called the application of statistics to such problems an enumerative study.

But the thing managers really need to know about is future outcomes and how they will be influenced by present decisions. There is no way of sampling the future. So sampling of the past has to go beyond mere characterisation and quantification of the outcomes. You are stuck with those and will have to take the consequences one way or another. Sampling (of the past) has to aim principally at understanding the causes of those historic outcomes. Only that enables managers to take a view on whether those causes will persist in the future, in what way they might change and how they might be adjusted. This is what Deming called an analytic study.

Essential to the ability to project data into the future is the recognition of common and special causes of variation. Only when managers are confident in thinking and speaking in those terms will their organisations have a sound basis for action. Then it becomes apparent that the results of inspection represent the occult interaction of inherent variation with threshold effects. Inspection obscures the distinction between common and special causes. It seduces the unwary into misguided action that exacerbates quality problems and reputational damage. It obscures the sad truth that, as Terry Weight put it, a disappointment is not necessarily a surprise.

The programme

  1. Drive out sensitivity to variation at the design stage.
  2. Routinely measure the inputs whose variation threatens product performance.
  3. Measure product performance too. Your bounded rationality may have led you to get (2) wrong.
  4. No need to measure every unit. We are trying to understand the cause system not segregate items.
  5. Plot data on a process behaviour chart.
  6. Stabilise the system.
  7. Establish capability.
  8. Keep on measuring to maintain stability and improve capability.

Some people think they have absorbed Deming’s thinking, mastered it even. Yet the test is the extent to which they are able to analyse problems in terms of common and special causes of variation. Is that the language that their organisation uses to communicate exceptions and business performance, and to share analytics, plans, successes and failures?

There has always been some distaste for Deming’s thinking among those who consider it cold, statistically driven and paralysed by data. But the data are only a means to getting beyond the emotional reaction to those two impostors: triumph and disaster. The language of common and special causes is a profound tool for building engagement, fostering communication and sharing understanding. Above that, it is the only sound approach to business measurement.

Sad news on railway suicide statistics

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I recently blogged about statistics of suicides on British railways here and here. Some very worthwhile programmes had been put in place with the objective of reducing these tragic deaths. However, my view at the point of my earlier posts was that this was a stable system of trouble, that there was neither a deteriorating trend nor any sign of improvement.

I now have the statistics for 2012/2013 to hand, released without any framing press notice. Here is the updated process behaviour chart.
RailwaySuicides2

Readers should note the following about the chart.

  • Some of the numbers for earlier years have been updated by the statistical authority.
  • I have recalculated natural process limits as there are still no more than 20 annual observations.
  • There is still no signal of improvement or deterioration.

I fear that this is the tough discipline of the chart. It confronts us with current reality and deprives us of the opportunity to find comforting messages. Only a signal on the chart would be evidence of improvement. Statistics are not there to be selectively reported only when they fit our wishes and hopes. Statistics are to be charted, and reported, and discussed, and used as a basis for managing any operation; year in, year out.

Remember that in leading any operation the manager is confined to the retreating picture in the rearview mirror. Without the process behaviour chart, the manager is deprived even of that rear view.

It is a sad picture but improvement only comes from confronting current failure and finding new ways to intervene and redesign. Nobody will benefit from an ultimately vain quest for comforting messages.

Trouble at the EU

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I enjoy Metro the UK national free morning newspaper. It has a very straightforward non-partisan style. This morning there was an article dealing with the European Union’s (EU’s) accounting difficulties. There were a couple of very telling admissions from an EU bureaucrat. We lawyers love an admission.

Aidas Palubinskas, from the European Court of Auditors, … described the error rate as ‘relatively stable from year to year’.

He admits that the EU’s accounting is a stable system of trouble. That is a system where there is only common cause variation, variation common to the whole of the output, but where the system is still incapable of reliably delivering what the customer wants. Recognising that one is embedded in such a problem is the first step towards operational improvement. W Edwards Deming addressed the implications of the stable system and the strategy for its improvement at length in his seminal book Out of the Crisis (1982). The problems are not intractable but the solution demands leadership and adoption of the correct improvement approach.

Unfortunately, the second half of the quote is less encouraging.

He said the errors highlighted in its report were ‘examples of inefficiency, but not necessarily of waste’.

This makes me fear that the correct approach is far off for the EU. Everything that is not efficient, timely and effective delivery of what the customer wants is waste, as Toyota call it muda. Waste represents the scope of opportunity for improvement, for improving service and simultaneously reducing its cost. The first step in improvement is taken by accepting that waste is not inevitable and that it can be incrementally eliminated through use of appropriate tools under competent leadership.

The next step to improvement is to commit to the discipline of eliminating waste progressively. That requires leadership. That sort of leadership is often found in successful organisations. The EU, however, faces particular difficulties as an international bureaucracy with a multi-partisan political master and a democratically disengaged public. It is not easy to see where leadership will come from. This is a common problem of state bureaucracies.

Palubinskas is right to seek to analyse the problems as a stable system of trouble. However, beyond that, the path to radical improvement lies in rejecting the casual acceptance of waste and in committing to continual improvement of every process for delivery of service.