Some of the literature reviews on a comprehensive test of the efficiency rubber
futures on the futures markets have emphasized the informational role that the markets
perform. The price information they yield facilitates both production and storage
decisions. For example, assuming the futures market is efficient, Cox finds empirical
evidence to indicate that the futures trading increased the information incorporated in a
commodity‟s spot prices more fully reflect available market information when there is
futures trading. Cox (1976: 1215-1237); Peck (1976: 407-423); Turnovsky (1979:
301-327); and Grossman (1989: 218). Cox argues that futures trading can alter the
amount of information reflected in expected prices because speculators aided by
futures trading may be more informed about future conditions and because the
information incorporated in a futures price can be acquired cheaply by individuals who
do not trade in the futures markets. Cox‟s empirical results are drawn from the onion,
potato, pork belly, cattle, and frozen orange juice markets.
The forward pricing role of the futures markets became important when trading
in contracts for non-storable commodities was initiated. Peck (1976: 407-423) revives
the notion of the forward pricing role and argues that the futures markets provide
forward prices that could be used by a producer in formulating the production
decision. Her paper consists of an examination of the effects a forward price might
have on the stability of commodity prices. The conclusions are that the futures markets
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dampen price fluctuations by facilitating the storage decision and that the producer use
of the futures price in production decisions creates converging price fluctuations.
These results are similar to those given in a much earlier discussion by Johnson (1947)
who argues that if producers made their production decisions in relation to forward
prices, greater individual and industry stability could be achieved.
Turnovsky (1979: 301-327) suggests that Peck‟s paper suffers from several
limitations. Turnovsky considers the implications of an efficient futures market for
commodity price stabilization. Theoretically, he shows the introduction of an efficient
futures market will tend to stabilize spot prices. This result is similar to Samuelson‟s
(1971: 335-337) demonstration that competitive speculation stabilizes prices to the
optimal extent - speculators buy low and sell high. The allocation of welfare gains or
losses from the introduction of a commodity futures market is also considered by
Turnovsky. It is found in general that the allocation of the benefits from a futures
market to the various groups in the economy tends to be an intractable exercise.
However, in the case where no private storage exists, it is found that the futures market
yields net gains to producers and losses to consumers. McKinnon (1967: 844-861) and
Turnovsky (1979: 301-327) both conclude that the introduction of an efficient futures
market will almost certainly stabilize spot prices and that its main benefits occur
through its effects on production decisions. It is also suggested that the introduction of
the futures markets may be an effective and cheaper alternative to buffer stock
stabilization.
These results may suffer from the fact that the price information provided by
the futures markets does not have a large enough time horizon to yield all of the
benefits alluded to by McKinnon and Turnovsky. Grossman (1989: 218) argues that
the private and social incentives for the operation of a futures market are a function of
how much information spot prices alone can convey from „informed‟ to „uninformed‟
traders in the market. He reasons that the trading activity of informed firms in the
present spot market makes the spot price a function of their information, and
uninformed traders can use the spot price as a statistic which reveals all of the
informed traders‟ information. However, he argues that the spot price will not reveal
all of the informed traders‟ information because there are many other random factors
that determine the price. With the introduction of a futures market, the uninformed
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firms will have the futures price as well as the spot price transmitting the informed
firms‟ information to them, and this is the informational role of the futures markets.
He seems to ignore the influence of random factors in determining the futures price
and the fact that spot and futures prices are likely to be determined simultaneously.
Stein (1987: 1123-1145) shows that it is the theoretically possible for the price
destabilization to arise with the introduction of more speculators. The new speculators
change the informational content of prices and affect the reaction of incumbent traders.
The entry of new speculators lowers the informational content of prices to existing
traders. Crain and Lee (1996: 325-343) found a high degree of correlation between
changing U.S. farm programs and changing spot and futures price variability. Some
farm programs raise price volatility while other programs tend to lower volatility. The
effect is so strong that they find the seasonality effects of volatility to not be as
important as the impact of farm programs.