Do you know your fixed-incomederivatives from your collater-alised debt obligations, youroptions from your futures? Orare you more knowledgeableabout Indiana Jones than DowJones? Whether you have stocksor a pension or are merely tryingto get the best price for your carinsurance, the invisible hand ofthe market makes the world goround, as Adam Smith taught us.

For generations universitiestaught The Wealth of Nationsbut showed little interest inanalysing real-world marketmovements, assuming no theoryworthy of the name could bewrung from such a maelstrom of numbers. Even thoughCambridge was founded at just the time Magna Carta was

formalising the right of foreignmerchants to trade in England, it took nearly 800 years for theuniversity to decide it needed abusiness school – and even thenit proved a hard sell. The firstAmerican business school –Wharton, in Philadelphia – was founded in 1881, theCambridge economics tripos in1903, the Judge Business Schoolnot until 1990.

Yet Cambridge has always lovednumbers. For centuries the cur-riculum was dominated by math-ematics, which had such cachetthat until the 1820s it was theonly route to an honours degree.Robert Malthus (Jesus 1784)invented modern demography;Charles Babbage (Trinity 1811)developed the earliest calculatingmachine; Alfred Marshall (St John’s 1862) pioneered theeconomic analysis of marketsand industries; John MaynardKeynes (King’s 1902) laid thefoundations for macro-economictheory; and Alan Turing (King’s1931) founded the subject wenow call computer science. Allstarted out as mathematicians.

Finance was central to TheGeneral Theory of Employment,Interest and Money (1936), andtwo of Keynes’s successors –James Meade (Trinity 1930) andRichard Stone (Caius 1931) –were awarded Nobel Prizes forEconomics for their work devel-oping modern national account-ing. Yet for putting Cambridgebelatedly on the internationalfinancial map we have to thankan American: the venture capitalist and philanthropist Bill Janeway (Pembroke 1965).

Attracted by the legacy ofKeynes, Janeway originally cameto Cambridge as a MarshallScholar to write a PhD on theWall Street Crash and Americandepression. ‘Cambridge wasextraordinary after Princeton,where I had spent my life shuttling from class after class.Suddenly I was given a lot ofresearch time, which I used to deeply immerse myself inKeynes. I loved his sense of theworld as a place of radical uncer-tainty in which we nonethelesshave to make decisions, the consequences of which we haveto live with forever. You getexactly the same issues inDickens’ Little Dorrit!’

Leading universities did not treatcapital markets finance as part ofeconomics because ‘economists

found it difficult to model thedynamic behaviour of boomsand busts’. As a result, as busi-ness schools developed, enclavesof academics interested infinance coalesced only slowly.The first serious attempt toexplain the behaviour of capitalmarkets came in the 1950s fromAmerican mathematicians whoused models drawn from physicsto develop ‘modern portfoliotheory’, but the evolution ofmore suitable models, based on economic principles andprobabilistic ideas, required newmathematical methodologiesand took rather longer.

Cambridge began to takefinance seriously in 1996 when it appointed Canadian MichaelDempster to the Judge BusinessSchool as its first professor offinance, but the real turningpoint came five years later whenBill Janeway – wealthy from athirty-year career providing pri-vate equity for high-tech start-ups – decided, with his wifeWeslie, to give Cambridge $20m to set up a CambridgeEndowment for Research inFinance (CERF). The idea, hesays, was ‘to look at how finan-cial mathematics had evolved inthe previous thirty or forty years– from historical, economic andinstitutional perspectives.’

CERF works with CambridgeFinance, a university-wideresearch initiative started in 2003by Dempster, mathematicianChris Rogers, and the econo-mists Hashem Pesaran and JohnEatwell. Today it embraces notjust those founding disciplinesbut lawyers and land economiststoo. The risk and uncertainty sur-rounding financial markets arethe common denominators. ‘If market volatility were only afunction of external events likefloods and earthquakes, riskmodels would be a lot simpler,’says Janeway. ‘It’s the behaviourof human beings that makesthem so complicated. What isrational for me depends on whatyou do, and so on.’ Using gametheory, for instance, mathemati-cians can now construct sophisti-cated models to simulate a richrepertoire of human reactions.

For mathematician Chris Rogersevery working day involves prob-ing randomness and risk. Theday we meet he has just cycledin across the fields from Harston,past autumnal hedgerows andfiery ash trees to the university’siconic new mathematics centre

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Calculated risksIf it’s risky, quantify it. If it’s uncertain, avoid it.Louise Simpson explores the extraordinaryworld of financial mathematics

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on Clarkson Road. ‘Finance isnot a science,’ he assures me.‘You can’t replicate 1963! It’sone thing looking at moleculesof water – we know they willalways behave in the same way.But you can’t apply physical lawsto a million people. They won’tobey identical rules even if theyare subject to the same inputs.’

Professor Rogers heads a lab ofaround fifteen researchers, allstudying financial mathematicswith an eye to becoming aca-demics or bankers. In recentyears the subject has acquiredcult status, he says. ‘In the twenty-first century maths is thelanguage of the educated classes.It’s central to everything. Take a train or turn on an electricalappliance and mathematics ispart of it.’ Every year Rogers’group takes about four top PhD students from the 20–30enquiries he receives. ‘You haveto do this face to face,’ he says,indicating a chalkboard coveredwith impenetrable equationsbehind him. ‘You can’t baseselection on paper qualificationsand testimonials. We ask poten-tial students to work throughsome basic maths modellingbefore progressing to harderstuff. If they can’t do that, I just wait for the interview to be over!’

The models Rogers’ team use topredict financial behaviour aremore sophisticated than most ofthose in use commercially. ‘Banksrely on quite basic models, somedating back a hundred years.They aren’t very interested innew models when they canmake so much money fromunsophisticated ones!’ At pres-ent, he’s analysing this summer’seconomic crash and developinginsurance pricing models forhuge but remote risks such ashurricanes and earthquakes. ‘For mathematicians modellinginsurance is very interestingbecause the premiums dependon how recent the last naturaldisaster was. Companies com-pete against one another, and ifthere hasn’t been a disaster for a while they relax and sell coverfor less. Then a big disaster likeHurricane Katrina comes along,the claims come in, and peoplerealise they’re vulnerable andraise their premiums.’ Financialmathematicians create modelsthat bring together all these vari-ables to predict what may ormay not happen in the future:rather like the Jeff Goldblumcharacter in Independence Day

who calculates the real risk ofthe alien invasion and usesmaths to save the planet. Handy stuff in a crisis!

Michael Dempster, the universi-ty’s foundation professor offinance, collaborates with ChrisRogers but in general approachesrisk and uncertainty from a morecommercial angle, applying theory to the markets. Educatedat Toronto, Carnegie Mellon andOxford (where he was also aprofessor), he has just moved to an emeritus position at theCentre for MathematicalSciences where his office is awash with boxes.

Cut through the technicalitiesand financial mathematics isn’tnecessarily conceptually complex,says Dempster. ‘Futures, forinstance, come out of our agri-cultural roots. They’re just con-tracts for the physical delivery of something in the future for aprice determined by the marketat delivery time. If a farmer has a contract for next year’s hogs,that stops the hog cycle whereprices are low so no one growshogs. If the price goes up,

everyone grows hogs and so theprice of hogs falls again. Withfutures contracts, the farmer isassured that next year he can sellhis hogs, so this sort of cyclicalpattern is erased.’

One of the biggest boosts tounderstanding financial marketscame with the Sputnik pro-gramme launched by the SovietUnion in 1957 to demonstratethe viability of space satellites.This really pushed out theboundaries of stochastic mathe-matics, says Dempster. ‘Scientistswere dealing with the randomeffects of the white noise of theuniverse, and the likelihood ofthis beach-ball-sized satellitebeing hit, driven off course,

exploding, or whatever. Andwhen the space-race was over,those same risk analysts mor-phed into financial mathemati-cians, working with problemsthat were pretty much parallel.’

Dempster enjoys creating modelsfor uncertainty as well as risk,but draws a strict distinctionbetween the two. ‘Having aheart attack is risky, but life afterdeath is uncertain. In otherwords, if you can apply proba-bilistic laws to something, you’redealing with risk (as you are withinsurance pricing). If you’re deal-ing with uncertainty, you can’tapply any laws because youdon’t have a clue what risk isentailed. Bayesian statisticiansdon’t accept this view, but that’sbecause – like many probabilistsworking in higher mathematics –they believe probability, evensubjective probability, willdescribe everything.’

Ten years on, the future of finan-cial mathematics in Cambridgeseems assured, thanks to theJaneways’ generosity and theacademic leadership of Dempsterand his colleagues in Cambridge

Finance. Only last month the uni-versity received a generous giftfrom Sir Evelyn de Rothschild(Trinity 1952) to fund a new pro-fessorship of finance that wouldfocus on venture capital. Newstudent courses are also comingon stream. The Judge BusinessSchool next year launches a one-year Master of Finance degree to add to its existing MPhils infinance and financial research.

Business degrees attract out-standing students from China,Korea, Japan and America, withas many women as men pro-gressing from them to work inthe world’s top banks. With luck,some will one day be able to giveback to society as generously asBill Janeway, for whom economic

progress is all about how wecompute and confront risk.‘Social progress is highly depend-ent on investments in innovativetechnology,’ he says. ‘We wouldbe nowhere without the risk takers of capital markets.’

Academics take pleasure in thesuccess of their students, so it’s no surprise to find MichaelDempster delighted that one ofhis recent graduates is alreadyrunning the Options desk at theUnion Bank of Switzerland inHong Kong. What’s perplexing is to discover that neither he norChris Rogers much fancies theirchances speculating on thestockmarket. They say it’s too risky. �

Louise Simpson (Girton 1982)directs the Cambridge office ofthe communications consultancyThe Knowledge Partnership

Number crunchers. From left: Chris Rogers, Michael Dempster and Bill Janeway

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