smallholder market participation concepts and evidence from eastern and southern africa abstract this paper reviews the evidence on smallholder market participation with a focus on staple foodgrains i e cereals in eastern and southern africa in an effort to help better identify what interventions are most likely to break smallholders out of the semi subsistence poverty trap that appears to ensnare much of rural africa the conceptual and empirical evidence suggests that interventions aimed at facilitating smallholder organization at reducing the costs of intermarket commerce and perhaps especially at improving poorer households access to improved technologies and productive assets are central to stimulating smallholder market participation and escape from semi subsistence poverty traps macroeconomic and trade policy tools appear less useful in inducing market participation by poor smallholders in the region

information to guide policy responses to higher global food prices the data and analyses required abstract national decision makers must understand the degree to which their country and population groups within it are exposed to the negative effects of higher global food prices or could exploit new economic opportunities offered by higher prices this paper provides a conceptual overview of the range of data and analyses that will permit leaders and analysts serving them to assess the broad implications of higher global food prices for a country and its population groups what we find is that there are a relatively small number of types of policy responses that governments might take in the face of a food price rise consequently relatively well defined sets of data need to be compiled and types of analyses used by government to generate the information needed to broadly guide efforts to prevent food price increases from becoming crises and to derive any possible benefits international joint action can be employed profitably both to collect this data and to build national capacity to conduct the analyses needed to guide policy formulation and general program design in the face of the risks and the opportunities of higher food prices and to evaluate the effectiveness of those policy responses

implicit delivery options and optimal delivery strategies for financial futures contracts abstract futures contract specification usually allow the short position some variation as to when where how much and what is to be delivered in this paper we derive the optimal delivery policy for the treasury bond futures contracts and find that our policy produces profits that are positive and statistically significant this indicates that future prices are too high in that the short position can earn profits by skillfully exercising his delivery options we find the actual delivery policies of market participants depart substantially from the optimal strategy the implications of these findings for futures traders and bond dealers are discussed

valuation and optimal exercise of the wild card option in the treasury bond futures market the chicago board of trade treasury bond futures contract allows the short position several delivery options as to when and with which bond the contract will be settled the timing option allows the short position to choose any business day in the delivery month to make delivery in addition the contract settlement price is locked in at 2 00 p m when the futures market closes despite the facts that the short position need not declare an intent to settle the contract until 8 00 p m and that trading in treasury bonds can occur all day in dealer markets if bond prices change significantly between 2 00 and 8 00 p m the short has the option of settling the contract at a favorable 2 00 p m price this phenomenon which recurs on every trading day of the delivery month creates a sequence of 6 hour put options for the short position which has been dubbed the wild card option this paper presents a valuation model for the wild card option and computes estimates of the value of that option as well as rules for its optimal exercise the treasury bond futures contract on the chicago board of trade gives several delivery options to the short position the quality option which allows the short to deliver any of several eligible delivery bonds has already been studied fairly extensively because many bonds are eligible to be delivered against the futures contract and the conversion factors used to adjust for the bond actually delivered do not perfectly reflect relative price differences the short side trader will choose to deliver the cheapest eligible bond kilcollin 71 presents a discussion and analysis of conversion factors and their effects on the optimal delivery bond gay and manaster 4 present a theoretical valuation model for the quality option when two classes of commodities with uncertain end of period spot prices may be delivered garbade and silber 3 provide a similar analysis and estimate parameters of the valuation formula for a variety of agricultural commodity futures kane and marcus 6 have used monte carlo simulations to value the quality option in the treasury bond futures market in contrast the various timing options embedded in the delivery process have received comparatively little attention one of the most important of these is the so called wild card option the wild card option arises because the futures market closes each trading day at 2 p m central standard time which locks in the futures settlement price for the rest of the day while the short trader has until 8 p m of each trading day in the delivery month to declare an intent to deliver

a cross section analysis of household demand for food and nutrients in tanzania abstract undernutrition and malnutrition are still problems of unacceptable proportions in many developing countries however the debate on the roles of income and other socio economic variables such as women s education and household size on food and nutrient demand continues this study examines the demand for food and nutrients amongst households in tanzania using recent survey data a quadratic almost ideal demand system quaids is employed to estimate price and expenditure elasticities as well as the impact of socio economic variables on food demand patterns a moment based instrumental variable approach is then used to analyse the determinants of nutrient demand the results show that income and other socio economic variables exert significant effects on the demand for food and nutrients the estimated expenditure elasticities for the nutrients range from 0 307 for iron to 1 26 for vitamin b12 the elasticities are higher for those micronutrients that are consumed through animal products and lower for those micronutrients that are mainly obtained through staple foods these results reflect the higher expenditure elasticities for meat fish eggs milk and milk products as well as fruits and vegetables relative to cereals and pulses reinforcing the assertion that the demand for vitamins a and b12 as well as calcium and zinc will increase with rising income

an empirical analysis of implicit delivery options in the treasury bond futures contract abstract assuming perfect frictionless and efficient markets this paper develops a framework to estimate the composite value of the quality wild card and end of month options implicit in the t bond futures contract the value of delivery options is shown to be the excess of forward price of the cheapest bond over its conversion factor times the exercise price of futures contract empirical results indicate that the option values over the last quarter of the nearby contract are on average less than 0 5 percent of the mean futures price which is substantially lower than the value reported by previous studies further scrutiny reveals that although the empirical estimates are contaminated by non synchronous bond data they are consistent with certain known theoretical properties of option values

the delivery option on forward contracts many futures contracts contain a delivery option which allows the short position a choice to deliver one of several varieties of a commodity several authors have argued that deliv ery options can have considerable value for a forward contract with a delivery option this paper shows that a continuously adjusted hedge will drive the value of the delivery option towards zero assuming perfect and frictionless markets tract the option to deliver one of several grades of a commodity on the delivery date recent papers by garbade and silber 3 and gay and manaster 4 have examined this delivery option and have suggested that this option reduces the futures price prior to the delivery date this paper examines a perfect market with continuous prices with an infinite number of deliverable varieties with ac tive forward markets for all deliverable varieties and without marking to market under these assumptions the value of the delivery option is shown to ap proach zero the paper shows that a continuously adjusted hedge exists that guarantees this result therefore the attachment of value to the delivery option

options on the minimum or the maximum of two risky assets analysis and applications this paper provides analytical formulas for european put and call options on the minimum or the maximum of two risky assets the properties of these formulas are discussed in detail options on the minimum or the maximum of two risky assets are useful to price a wide variety of contingent claims of interest to financial economists applications discussed in this paper include the valuation of foreign currency debt option bonds compensation plans risk sharing contracts secured debt and growth opportunities involving mutually exclusive investments

a comparison of futures and forward prices abstract this paper uses the pricing models of cox ingersoll and ross 1981 richard and sundaresan 1981 and french 1982 to examine the relation between futures and forward prices for copper and silver there are significant differences between these prices the average differences are generally consistent with the predictions of the futures and forward price models however these models are not helpful in describing intra sample variations in the futures forward price differences this failure is apparently caused by measurement errors in both the price differences and in the explanatory variables

an ex post valuation of the quality option implicit in the treasury bond futures contract abstract this paper develops three empirical estimates of the value of the quality delivery option implicit in the treasury bond futures contract a an ex ante value as given by the excess of forward price of the cheapest to deliver bond over its conversion factor times the futures price b an ex post value equal to the payoffs to a strategy of buying and holding a short futures long forward position at the start and delivering the cheapest bond at the expiration of futures contract and c another ex post value equal to the sum of payoffs to a continuous rollover strategy involving a short futures long forward position in the cheapest to deliver bonds three months prior to delivery the average values of the three estimates are 464 329 and 2 075 respectively the differences among the three estimates appear to be largely due to nonsynchronous spot futures data

the delivery option on forward contracts a note a number of futures contracts conveys to the short position various delivery options re garding the quality and exact timing of delivery moreover the compensation to the long position is not solely determined by the market value of the delivered asset at the time of delivery sometimes the long position can hedge this delivery risk by holding an appropriate portfolio of the underlying asset it often has been stated that whenever the long position can form a dynamic hedge against the delivery risk the delivery option has a zero value this paper demonstrates the implication of such erroneous intuition to the pricing of options it is shown that the root of the issue is the property of diffusion processes whereas within a given time interval a random variable either will never cross a given boundary or else cross it an inflnite number of times

food price changes and household welfare what do we learn from two different approaches the use of a marginal approach can significantly distort the predicted effects of large price variations on monetary welfare over the medium to longer term this paper aims at shedding some light

nominal contracts in a bimetallic standard as its central feature a bimetallic standard grants nominal debtors an option to deliver either of two metals with results from the option pricing literature construction of a formula to evaluate the bimetallic option in debt instruments is straightforward with this formula one can compute the option value in a wide range of nineteenth century u s treasury securities posession of the option values permits an adjustment of the yields on u s securities to make them comparable to yields on nonmetallic european securities evaluating the option allows the estimation of transfers from debtors to creditors copyright 1986 by american economic association

intra day tests of the efficiency of the treasury bill futures market in this paper we use intra day prices to examine the efficiency of the treasury bill futures market the use of intra day data allows us to carefully match in time trades in the futures and cash markets by matching trades and allowing delays between observing apparent inefficiencies and the trade we are examining realistic trading strategies we find profitable arbitrage swaps and a preferred strategy for initial purchase these profits do not depend on an assumption of an equilibrium model hence these tests are direct tests of efficiency rather than a joint test of efficiency and equilibrium t his paper examines the efficiency of the treasury bill futures market this subject has been examined before by capozza and cornell 1979 cornell 1981 lang and rasche 1978 rendleman and carabini 1979 vignola and dale 1979 poole 1978 and puglisi 1978 there are a number of reasons why this paper makes an important contribution to the literature the first reason is that by using trade by trade futures prices we can make more realistic assumptions about the pnces at which trades could have taken place this paper uses intra day prices to examine efficiency prior studies at best used closing prices to examine apparent inefficiencies and assumed that transactions took place at these closing prices there are two problems with this procedure first simultaneous transactions cannot actually occur at closing prices there is almost an hour difference between the closing of the chicago futures and new york spot markets thus when the closing spot market price is observed the futures market has been closed for about an hour closing prices could be used to judge apparent discrepancies however it would be necessary to execute trades at the open making decisions based on closing prices and then assuming trades can take place at these prices is an approximation which could significantly affect results in addition using only closing prices ignores any intra day trades which could lead to profits in this study we match in time intra day prices in the spot and futures market these matched prices are used to identify apparently profitable trading rules we then assume trades take place at prices which are observed later in the day this is a test of a trading rule which an investor could actually follow as we discuss later in the paper our results differ from prior studies these differences are primarily due to using intra day prices and carefully matching times so that information used to initiate trades would actually be available to the investor at the time of the trade the second reason is that we examine more complex trading strategies than those which have been employed in other studies the random walk literature provides a useful analogy the original random walk studies simply correlated past and future prices or returns later studies examined filter rules and other more complicated trading rules in this study we employ alternative trading rules of increased complexity to test for the existence of trading profits finally we explicitly examine the consequence of t bills futures contracts being futures rather than forward contracts futures contracts unlike forward contracts involve flows every settlement day the intermediate cash flows on futures contracts can affect the profitability of any strategy the only prior study that even considered this effect is the one by rendleman and carabini 1979 they used the theoretical model of cox ingersoll and ross 1981 to try to estimate whether the difference between forward and futures prices was likely to be large enough to affect the payoff from alternative trading strategies this is a useful first attempt however ultimately the effect of daily settlement or marking to the market has to be examined directly as part of trading strategies to see if it affects the outcome of these strategies there are other problems with prior studies these involve gross estimates of prices and averaging data in a way that can mask inefficiencies since these problems are discussed in some detail in rendleman and carabini there is no reason to review them further here probably no area in finance has received more attention than the efficiency literature the reader may well wonder why even given the approximareceived for publication august 23 1982 revision accepted for publication may 20 1983 new york university new york university and baruch college respectively the authors would like to thank the center for the study of futures markets at columbia business school for financial support

prices and unit values in poverty measurement and tax reform analysis researchers often use unit values household expenditures on a commodity divided by the quantity purchased as proxies for market prices when calculating poverty lines and estimating consumer demand equations such proxies are often needed because community price surveys in developing economies are either absent or suffer quality problems however using unit values may result in biases due to measurement error and quality effects in a household survey experiment information on prices was obtained in three ways from unit values from a market price survey and from the opinions of householders who were shown pictures of items and asked to report the local price the three sets of price data are used to calculate poverty lines estimate price elasticities and analyze marginal tax reforms there are substantial biases when unit values are used as a proxy for market price even when sophisticated correction methods are applied performance was better for the price opinions of household members the results highlight the importance of price collection methods and the need to consider the wider costs of having potentially unreliable community level price data

how does real exchange rate influence income inequality between urban and rural areas in china abstract the channels through which the real exchange rate influences urban rural per capita real income inequality are analyzed using yearly data for 28 chinese provinces due to the higher share of tradable goods produced in urban than rural areas the real depreciation of the chinese currency raised the urban bias contrary to the effect usually expected this rise was however mitigated because of the impact of the exchange rate on the urban rural consumer price ratio real public wages and the ratio of industrial agricultural protection rates it disappeared for coastal provinces due to the strong development of outward oriented rural industrial activities

a class of proximity sensitive measures of relative deprivation abstract we introduce a new class of generalized measures of relative deprivation the class takes the form of a power mean of order p a characteristic of the class is that depending on the value of the proximity sensitive parameter p the class is capable of accommodating both a decreasing weight the case of p 1 and an increasing weight the case of p 0 1 accorded to given changes in the incomes of the individuals who are wealthier than the reference individual depending on their proximity in the income distribution to the reference individual

the relation between forward prices and futures prices abstract this paper consolidates the results of some recent work on the relation between forward prices and futures prices it develops a number of propositions characterizing the two prices these propositions contain several testable implications about the difference between forward and futures prices many of the propositions show that equilibrium forward and futures prices are equal to the values of particular assets even though they are not in themselves asset prices the paper then illustrates these results in the context of two valuation models and discusses the effects of taxes and other institutional factors

forward and futures prices evidence from the foreign exchange markets empirical studies of the treasury bill markets have revealed substantial differences between the futures price and the implied forward price these differences have been attributed to taxes transaction costs and the settling up procedure employed in the futures market this paper examines the forward and futures prices in foreign exchange in an attempt to distinguish between the competing explanations empirical studies of the treasury bill market have revealed differences between the futures price or rate and the implicit forward price derived from the term structure of interest rates 1 these differences have generally been attributed to market imperfections such as taxes and transaction costs see for example arak 1 capozza and cornell 2 and rendelman and carabini 6 recently however cox ingersoll and ross 3 henceforth cir derived a model in which forward and futures prices need not be equal even in perfect markets without taxes as long as interest rates are stochastic the significance of the cir effect may be hard to investigate using only data from the bill market because of the potentially complicating effects of taxes and transaction costs unique to this market by using data from the foreign exchange market we are able to eliminate the tax effect and reduce the impact of transaction costs the question we address is whether the discrepancies observed in the treasury bill market are also observed in the foreign exchange market if they are then we have evidence that the differences are due to a combination of the cir effect and the transaction costs common to both markets if they are not then either the magnitude of the cir effect is much less in the foreign exchange market or the treasury bill results are due to the unique tax treatment and transaction costs of that market this paper is organized as follows in section i the trading mechanics of the forward and futures markets in foreign exchange are discussed section ii reviews the explanations for the discrepancies between the forward and futures prices for treasury bills the institutional differences between the foreign exchange and bill markets are also summarized to show which of these explanations cannot apply to the foreign exchange market in section iii the data are decribed and the empirical results are presented the conclusions are summarized in the final section