Foreign exchange platform puts the brakes on high-frequency traders

EBS has changed its rules to discourage algobots.

EBS, a major interbank trading platform in in the foreign exchange market, is considering imposing a major change in the way it runs its market in order to discourage high-frequency trading from taking place.

EBS currently runs on the principle of "first in, first out" trading, where trades are dealt with in the exact order they are made. That is the way most people expect the market to work – but it also gives an advantage to those who can get their trades in quickest. That leads to the arms race that high-frequency trading has seen in the last few years, where traders pay to place their servers close to the exchange, to whittle off those last few microseconds.

Instead of this model, EBS is considering bundling together incoming trades and dealing with them in a random order. That way, every trade that came in in (for example) the tenth of a second between 12:00:00.0 and 12:00:00.1 would be grouped together and dealt in a random order, removing the advantage that the trader who got in at 12:00:00.01 would normally have.

Speaking to the FT, the chief executive of EBS explained why the company has made the decision:

The first twenty years of algorithmic trading have added great transparency and led to the compression of spreads – all great things. But there is a line beyond which marginal speed and smaller trade sizes add no value and actually harm the markets. At some point we, the public markets across asset classes, crossed that line.

The ‘first in, first out’ model sounds fair and plausible, but in modern public markets it implies ‘winner takes all’.

The classic example of how high(er)-frequency trading can have positive effects comes from the fact that the desire to shave seconds off the response time to financial information is the reason why the undersea cables linking London to New York are so high quality. Without that motivation to profit, the cables might not have been laid for decades after, and certainly wouldn't be as fast as they are now. (In fact, the USD/GBP exchange rate is still known as "cable" now, after the first transatlantic cable laid in 1858).

But as the speed of trades has increased ever higher, the side-benefits are shrinking. The difference in liquidity between a market where a tenth of a second and a thousandth of a second matters is minuscule; even if spreads might be a tiny bit tighter than they otherwise would be, no normal trader is helped by that "improvement".

So EBS's speed limit is a welcome step. By dealing with trades in a semi-random order, it removes the incentive to spend millions on shaving off the smallest fractions of time. Ironically, the companies which will benefit most in the short term are the high-frequency traders themselves, who already have the technology to trade speedily, and now don't need to worry about investing more on ever-diminishing returns. But eventually, more and more traders will match that capability, until the market becomes a level playing field again.

The other reason why traders – even high-speed ones – ought to thank EBS is that if the exchanges get HFT under control, then there's one less reason for governments to step in. Discouraging high-frequency trades is one of the strongest reasons for introducing a financial transaction tax. That hits everyone, not just the speedy traders.

A new data-centre in Manhattan. Photograph: Getty Images

Alex Hern is a technology reporter for the Guardian. He was formerly staff writer at the New Statesman. You should follow Alex on Twitter.

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Inside Big Ben: why the world’s most famous clock will soon lose its bong

Every now and then, even the most famous of clocks need a bit of care.

London is soon going to lose one of its most familiar sounds when the world-famous Big Ben falls silent for repairs. The “bonging” chimes that have marked the passing of time for Londoners since 1859 will fall silent for months beginning in 2017 as part of a three-year £29m conservation project.

Of course, “Big Ben” is the nickname of the Great Bell and the bell itself is not in bad shape – even though it does have a huge crack in it.

The bell weighs nearly 14 tonnes and it cracked in 1859 when it was first bonged with a hammer that was way too heavy.

The crack was never repaired. Instead the bell was rotated one eighth of a turn and a lighter (200kg) hammer was installed. The cracked bell has a characteristic sound which we have all grown to love.

Big Ben strikes. UK Parliament.

Instead, it is the Elizabeth Tower (1859) and the clock mechanism (1854), designed by Denison and Airy, that need attention.

Any building or machine needs regular maintenance – we paint our doors and windows when they need it and we repair or replace our cars quite routinely. It is convenient to choose a day when we’re out of the house to paint the doors, or when we don’t need the car to repair the brakes. But a clock just doesn’t stop – especially not a clock as iconic as the Great Clock at the Palace of Westminster.

Repairs to the tower are long overdue. There is corrosion damage to the cast iron roof and to the belfry structure which keeps the bells in place. There is water damage to the masonry and condensation problems will be addressed, too. There are plumbing and electrical works to be done for a lift to be installed in one of the ventilation shafts, toilet facilities and the fitting of low-energy lighting.

Marvel of engineering

The clock mechanism itself is remarkable. In its 162-year history it has only had one major breakdown. In 1976 the speed regulator for the chimes broke and the mechanism sped up to destruction. The resulting damage took months to repair.

The weights that drive the clock are, like the bells and hammers, unimaginably huge. The “drive train” that keeps the pendulum swinging and that turns the hands is driven by a weight of about 100kg. Two other weights that ring the bells are each over a tonne. If any of these weights falls out of control (as in the 1976 incident), they could do a lot of damage.

The pendulum suspension spring is especially critical because it holds up the huge pendulum bob which weighs 321kg. The swinging pendulum releases the “escapement” every two seconds which then turns the hands on the clock’s four faces. If you look very closely, you will see that the minute hand doesn’t move smoothly but it sits still most of the time, only moving on each tick by 1.5cm.

The pendulum swings back and forth 21,600 times a day. That’s nearly 8m times a year, bending the pendulum spring. Like any metal, it has the potential to suffer from fatigue. The pendulum needs to be lifted out of the clock so that the spring can be closely inspected.

The clock derives its remarkable accuracy in part from the temperature compensation which is built into the construction of the pendulum. This was yet another of John Harrison’s genius ideas (you probably know him from longitude fame). He came up with the solution of using metals of differing temperature expansion coefficient so that the pendulum doesn’t change in length as the temperature changes with the seasons.

In the Westminster clock, the pendulum shaft is made of concentric tubes of steel and zinc. A similar construction is described for the clock in Trinity College Cambridge and near perfect temperature compensation can be achieved. But zinc is a ductile metal and the tube deforms with time under the heavy load of the 321kg pendulum bob. This “creeping” will cause the temperature compensation to jam up and become less effective.

So stopping the clock will also be a good opportunity to dismantle the pendulum completely and to check that the zinc tube is sliding freely. This in itself is a few days' work.

What makes it tick

But the truly clever bit of this clock is the escapement. All clocks have one - it’s what makes the clock tick, quite literally. Denison developed his new gravity escapement especially for the Westminster clock. It decouples the driving force of the falling weight from the periodic force that maintains the motion of the pendulum. To this day, the best tower clocks in England use the gravity escapement leading to remarkable accuracy – better even than that of your quartz crystal wrist watch.

In Denison’s gravity escapement, the “tick” is the impact of the “legs” of the escapement colliding with hardened steel seats. Each collision causes microscopic damage which, accumulated over millions of collisions per year, causes wear and tear affecting the accuracy of the clock. It is impossible to inspect the escapement without stopping the clock. Part of the maintenance proposed during this stoppage is a thorough overhaul of the escapement and the other workings of the clock.

The Westminster clock is a remarkable icon for London and for England. For more than 150 years it has reminded us of each hour, tirelessly. That’s what I love about clocks – they seem to carry on without a fuss. But every now and then even the most famous of clocks need a bit of care. After this period of pampering, “Big Ben” ought to be set for another 100 or so years of trouble-free running.

The Conversation

Hugh Hunt is a Reader in Engineering Dynamics and Vibration at the University of Cambridge.

This article was originally published on The Conversation. Read the original article.