Winners and losers: “The more often people look at their portfolios, the less willing they will be to take on risk, because if you look at it more often, you will experience more lossesm” says Richard Thaler. Photograph: Spencer Platt/Getty Images

In a world populated by Spock-like econs, all of us would conduct our financial affairs in a rational, self-interested manner. However, the world is p(...)

NYSE traders: Critics say cap-weighted indices run the risk of significant declines if a handful of constituent stocks tumble and that tracker funds will end up being too invested in overpriced stocks, and too little in underpriced stocks. Photograph: Brendan McDermid/Reuters

Traditionally, investors had two choices – track stock markets by buying low-cost index funds, or opt for more expensive active funds that try to beat(...)

Winner’s curse: Apple shareholders suffered a torrid time shortly after the company smashed the market capitalisation record in August 2012, descending from a high of $705 (€520) per share to a low of $385 (€284) just seven months later. Photograph: David Paul Morris/Bloomberg

All over the world, the “top dogs” in stock sectors go on to suffer years of underperformance, according to prominent money manager Rob Arnott. Just a(...)

Traders work on the floor of the New York Stock Exchange: Research indicates that returns are usually dictated more by chance than skill. Photograph: Justin Lane/EPA

Does luck trump skill in investment. Research indicates that returns are usually dictated more by chance than skill, and it’s hard to tell the differe(...)

Traders working on the floor of the New York Stock Exchange earlier this month. The momentum effect can be found in 212 years of US data. Photograph: Reuters/Brendan McDermid

It sounds too good to be true – just buy stocks that are rising, and forget all that agonising over company balance sheets and earnings reports and so(...)

Nobel Prize winner Eugene Fama

Renowned value investor Jeremy Grantham has harsh words for Alan Greenspan, Ben Bernanke and incoming Federal Reserve chief Janet Yellen in his latest(...)

Picking stocks: investors have reason to be grateful to devotees of the efficient market hypothesis and behavioural finance.  photograph: andrew burton/getty images

Are markets efficient, or are investor actions governed by animal instincts? Is it pointless trying to beat the market, or are stocks prone to systema(...)

Economist, author and Yale University professor Robert Shiller

Eugene Fama’s academic career is built on the efficient market hypothesis (EMH), dismissed by Robert Shiller as “one of the most remarkable errors in(...)

Planet Business

Image of the week: Nobel pride Robert Shiller had a lot to be proud of before any committee for the Nobel economics prize got involved, but still(...)

Robert Shiller: has explored different ways in which asset prices can behave strangely

At first glance it is tempting to laugh at the 2013 Nobel Prize in Economics being shared between an academic who invented the “efficient markets hypo(...)