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In essence, all markets are prediction markets. The value of assets traded in a market depends on
information that is not fully revealed and will not be known for some time, if ever. Market
valuations are explicitly or implicitly predictions of that unknown information, perhaps the future
value of a commodity, the expected cash flows generated by a firm, or the outcome of a potential
corporate merger.
While commodities futures are often used as financial instruments to hedge long or short positions,
the markets also reward traders with better information while punishing those with worse
information. Giving traders incentives to reveal good information is the core function of
prediction markets, even where no underlying assets, in the traditional sense, are available to be
traded. Prediction markets trade future events or outcomes, and the settling process amounts to
using a documented and published formula to determine winners and losers and to pay out incentives.
Many experiments and real-world tests show that market mechanisms can be implemented simply to
create predictions and that these systems work rather well.
Perhaps the best known of all prediction markets are the Iowa Electronic Markets, which enable
traders to forecast the outcomes of future elections. The power of these markets to generate
forecasts accurate and stable enough to inform decision makers has been demonstrated for nearly two
decades [5]. Another set of experiments at Hewlett Packard demonstrated the ability of prediction
markets to call future sales more effectively than traditional forecasting processes [6].
In our research at Intel we are extending the idea of prediction markets to create "forecasting
markets," which are essentially prediction markets or similar IAMs integrated into the company's
standard, ongoing forecasting processes. Participants reveal not just an expected outcome but a
series of expected outcomes for the same variable over time. So, the forecasting market captures
individual and collective assessments about trends such as increasing or decreasing demand just as
weather forecasts anticipate warming and cooling trends.
We believe that three factors enable markets to outperform other types of forecasting systems and
more effectively move information from source to decision maker. First, the features of anonymity
and incentives work together to draw out good information. The experiments of Kay-Yut Chen and
Charles Plott at Hewlett Packard suggest that people provide the best information when rewarded to
do so and when protected from potential ramifications of expressing their honest opinions.
Incentives encourage participants to search for the best information they can find and reward
trading behavior that is unbiased. Anonymity helps prevent biases created by the presence of formal
or informal power, the social norms of group interaction, and expectations of management. We found
many individuals at Intel who told us that their opinions sometimes differ from stated targets or
unstated expectations. Looking back at forecasts that were off substantially, we have been told
that teams sometimes did not believe the forecast they published but were pressured, perhaps
overtly, to adjust forecasts upward or downward. To the extent anonymity and incentives curb bias
and motivate the hunt for good information, they should improve the signal created by market
mechanisms.
Second, the simple mechanism of aggregating data through a survey or market has two remarkable
properties. It smoothes results over time, which is great for guiding supply, and it tends to
produce a group forecast more accurate than the forecast of at least a majority of individual
participants. A study by Scott Page demonstrated that even among a fairly homogeneous group this
effect holds true. In the context of forecasting selection order in professional sports drafts, he
found that averaging the individual forecasts of experts soundly outperformed the forecasts of any
individual [7].
Finally, in many forecasting examples it has been found that increasing the diversity of a pool of
participants increases the accuracy of the collective forecast. As long as each additional
participant brings some information, adding more, diverse opinions improves the collective
judgment. This condition holds true in many cases because good information tends to be positively
correlated and sums, while errors are often negatively correlated and cancel [8].
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