Alex Steer

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The Titanic, risk and uncertainty

1896 words | ~9 min

It's a hundred years since the Titanic sank. With the centenary, a lot of the questions about why the ship went down are being raised again. For me, the Titanic case is an important reminder about the relationship between risk and uncertainty, and how we react to extreme events.

Fates and flaws

Thomas Hardy, in his poem The Convergence of the Twain, saw the loss of the Titanic rather typically as an act of God or Fate against human vanity:

The Immanent Will that stirs and urges everything
Prepared a sinister mate
For her — so gaily great —
A Shape of Ice, for the time far and dissociate.

And as the smart ship grew
In stature, grace, and hue,<
In shadowy silent distance grew the Iceberg too.

Alien they seemed to be;
No mortal eye could see
The intimate welding of their later history,

Or sign that they were bent
By paths coincident
On being anon twin halves of one august event.

There is a touch of this, too, in the Spectator's reaction, from the 20th April 1912, which  it has re-published on its blog this week.

The destruction of the largest ship afloat on her maiden voyage, of a ship reputed to be unsinkable, of a ship followed everywhere with admiring thoughts as the last word in ingenuity, in luxury, and in the impressive accomplishments of science, brings to every thoughtful person a deep sense of powerlessness, of smallness, and humility. Even in these moments of crushing personal sorrow one is conscious — perhaps only to deepen the sorrow — of the overwhelming reverses of human confidence.

Happily, though, the article changes course fast, and shows an early public interest in the forensics of the disaster:

Although we do not know as we write these lines the details of the wreck, it is certain that the 'Titanic' struck an iceberg, and that there were not enough boats to take off more than about one in every three of the passengers. All the lifeboats carried by the 'Titanic' were picked up by the ‘Carpathia,' and the passengers in them — chiefly women and children — were saved. Although there was a slight swell there was no wind, and one cannot possibly escape from the conclusion that if there had been enough boats all the passengers might have been saved. Most people have learned with astonishment that it is possible for a ship like the ‘Titanic' to pass the Board of Trade tests with an insufficient number of boats.

I'd like to stick with the Spectator piece because it's so unusual. Looking back at archive material from the time, it's clear that in the days and weeks after the sinking the analysis of causes became increasingly sentimental. Yes, valuable criticisms like the one above, or the fault with the watertight bulkheads, were identified and raised. But we have also ended up with a long tradition of thought about the Titanic which tries to identify 'human confidence' or other moral flaws as the real reason the ship went down. From cowardly owners, to unwise claims about unsinkability, to a rash captain's decision to sail too close to the ice.

Here's how the Baltimore Morning Sun put the matter, just three days after the event:

Editorial Cartoon depicting Death playing cards

Image from the Library of Virginia, used with thanks.

The Titanic sinking was seen as a tragedy, and thinking about tragic events in the early decades of the 20th century centred largely on the idea of the 'tragic flaw' in human character that inevitably leads to disaster. For a scholarly exposition of this, see for example Oxford Professor of Poetry A.C. Bradley's Shakespearean Tragedy, published in 1904. The Titanic seemed to have no shortage of Bradleian tragic figures. That same mode of thinking can be seen in James Cameron's 1997 film Titanic, where you can pretty much pick which combination of character flaws (by Captain Smith, Mr Ismay, Mr Andrews, etc.) led to the disaster.

What's important about this line of analysis is the uniqueness. We try to see what was uniquely wrong with the Titanic that led to its demise - so of course it's easy to look at the unique combination of people who were on it, or the unique marketing claims that were made about the unsinkability of the ship. With the centenary we see a lot of this 'unique tragic flaw' theory turning up again in new clothes - such as Francis Wilson's Wall Street Journal piece, 'How bad management helped sink the Titanic', which is really just a Bradleian tragic analysis dressed up in MBA-speak.

Burying the survivors

Here's the problem with the 'unique tragic flaw' way of looking at extreme events. You ignore all the ships that didn't sink in 1912.

With a grim irony, the cognitive error that leads us to focus on the Titanic is called 'survivorship bias'. I don't have figures to hand, but imagine that in 1911-12 a hundred large cruise ships set off across the Atlantic, all similarly built and provisioned. Only one of them hits an  iceberg, and sinks, and causes the deaths 1,500 people.

We tend to look at the one that sank and ask, 'What was different?' That's a natural question - but it leads us to attribute all the causes of the disaster to things that were different about Titanic. And that leads us to assume, without questioning the evidence, that all the causes of the sinking were aberrations - things about Titanic, or its crew, that were unique. Specifically, we end up with the idea that the Titanic took unique risks, and paid the price.

Gary Cooper puts this superbly in an article on the ship's captain, Edward Smith, on the BBC News site:

Though Smith was undoubtedly a forceful sailor who pushed his ships hard in conditions that may have daunted other captains, it is a fact of history that providing the weather was calm and clear - as it was that night - it was not unusual for any captain to sail ships into ice regions at speed and several captains from other shipping companies testified to this at the disaster inquiries. [my emphasis]

Our survivorship bias tells us that Titanic must have done something abnormal - from offending the fates to sailing too fast, too close to the ice. In other words, the problem was one of risk.

In fact, it's just as likely that the problem was not risk. To use Frank Knight's model, risk exists within a model where the potential probability of outcomes is known. If you and I flip a coin to decide who wins it, you know there is a 50% risk of loss. In scenarios where you can't calculate all the factors, we're not talking about risk - we're talking about uncertainty. In a highly uncertain situation, you can do all the things you normally do, and have a completely unpredictable outcome.

It seems the builders and owners and operators of the Titanic did the same as the builders, owners and operators of other ships. It's just that they happened to hit an iceberg. Of course, they had watertight bulkheads and lifeboats designed to cope with certain levels of damage. In other words, they treated icebergs and other events as calculable risks. Like the risk-management models that failed during the financial crisis, they assumed that the chances of a catastrophic event were low enough not to be worth insuring against. And in most cases, they were right - but in the Titanic's case, they were unprepared.

Futurists tell you that trying to calculate the risk from extreme events is pointless. Extreme events operate in the domain of uncertainty, and there's just not enough data (because they're so rare) to model the probability accurately. All you can do, in the end, is try to be resilient against the impact of those extreme events that you can imagine. And if you're a shipping company whose goal is to travel at high speed through the icy waters of the North Atlantic, you can definitely imagine a collision with an Iceberg. By getting hung up on likelihood, the White Star Line seem to have been blinded to possibility - the idea that a big enough Iceberg could destroy a whole ship, not just disable part of it. By this reckoning, the loss of the Titanic wasn't anything unique to do with the Titanic - it was a failure of resilience throughout the entire fleet, that just happened to make itself known one April night.

I'm going to end with a long quote from the 1912 Spectator piece. More than anything I've read on the subject from the last hundred years, this captures the difference between risk and uncertainty, the need for resilience, but also the inevitability of surprise.

The truth is, as we said the other day in writing about the Oceans, that every passenger ship puts to sea with the assumption that disaster will not happen. Far too much is taken for granted. The whole subject ought now to be threshed out and the proper provision of boats or rafts insisted on for ships of whatsoever size they may be. Even if seamen declare it impossible to manage more than an inadequate number of life boats, we cannot see why other means of life saving should not be perfected, such, for example, as having the top deck entirely detachable, so that in the last resort it could be floated off in sections, each of which would be a duly equipped raft. As for increasing the buoyancy of the ship herself we do not know whether experiments which are being tried with submarines would be possible with ships of great size. Perhaps not; the inflation of special floats in an emergency would probably not be possible on a large scale. But, however that may be, it is necessary seriously to meet the tragically established fact that all the bulkheads of the largest ship in the world may be so damaged, strained, or knocked away that she will sink just like a cheaply built tramp steamer.

# Alex Steer (15/04/2012)