does the great recession imply the end of the great moderation international evidence in this paper we examine whether or not the great recession had a temporary or permanent effect on output growth volatility after years of low macroeconomic volatility since the early eighties based on break detection methods applied to a set of advanced countries our empirical results do not give evidence to the end of the great moderation period but rather that the great recession is characterized by a dramatic short lived effect on the output growth but not on its volatility we show that neglecting the breaks both in mean and in variance can have large effects on output volatility modeling based on garch specifications

a comprehensive analysis of farmland value determination a county level analysis this study develops a comprehensive model of farmland value determination to analyze the effects of various economic variables such as net farm income government payments macroeconomic factors and demographic conditions on farmland values for the counties along the snake river valley in idaho land values net farm income and population show considerable variation among the counties therefore use of county level cross sectional and time series data helps to assess the impacts of various factors on land values more accurately the empirical results show that net farm income wheat yield population and credit availability have positive effects and property tax rates interest rates and debt to asset ratio have negative effects on farmland values

labor supply of husbands and wives a simultaneous equations approach labor supply functions for married men and women are formulated as a dynamic simultaneous equations system which is estimated using panel data controlling for fixed individual effects allows marginal labor supply responses to be disentangled from permanent patterns in hours worked due to assortative mating the results suggest that the labor supply of husbands and wives without pre school children is not jointly determined in the short run while families with young children exhibit strong interactions in work hours and negative cross earnings effects neither the joint utility model of family labor supply nor an ad hoc traditional family model is supported by these results the data are for the united states and concern 381 couples from the denver income maintenance experiment excerpt

distinguishing between whole farm vs partial farm participation in the conservation reserve program by distinguishing between the decision to participate in the conservation reserve program crp and the decision for whole farm vs part farm participation we model participation as separate binary decisions our results suggest the farm characteristics and other factors affect the decision to participate in crp differently than the decision regarding whole farm vs part farm participation this model formulation also helps to clarify the conditions under which the effect of crp payments on the acreage enrolled in the program is positive or negative

cash rents and land values in u s agriculture a firm level land valuation model is deduced which depends on the expected growth rate in net cash returns to land inflation expectations and property income and capital gains taxes it is then aggregated to obtain an aggregate two sector land valuation model that model is then estimated for twenty four individual states for the period 1960 81 in addition a pooled cross sectional regression model is estimated combining the twenty four state data the model results demonstrate that significant state differences exist in the land market and that in many states agricultural land values are influenced by nonagricultural demand for land

real options approach to inter sectoral migration of u s farm labor the core of the literature on inter sectoral labor migration is based on net present value models of investment in which individuals are assumed to migrate to take advantage of positive wage differentials in this article we argue that a real options approach taken together with the adjustment costs associated with sectoral relocation may provide a basis for explaining the migration of farm labor out of the agricultural sector given the irreversibility of migration decisions and uncertainty in the economy potential migrants might choose to postpone migration even in the face of positive wage differentials using annual u s employment data from between 1948 and 2009 our results indicate that large elasticities between economic incentives and out farm migration are observed after a high threshold of wage differentials between farm and off farm sectors is surpassed

farming efficiency and the determinants of multiple job holding by farm operators the extent to which farm families engage inoff farm employment activities is a topic ofcentralimportancetounderstandingthe nan cial well being of farm households the degreeof nancial stress experienced by u s farmfamilies is always a concern to policy makers yet policyconsiderationsoftenignorethesub stantial involvement of most farm householdsin nonfarm labor markets it has been shownthat whentheentirefarmhouseholdisconsid ered the average u s farm household hasa higher total income and much greater assetholdings than is the case for nonfarm house holds see e g goodwin mishra et al pre sented data for 2000 suggesting that when allfarms are considered 92 of total householdincomecamefromnonfarmsources ofcourse such gures depend on how one chooses to de neafarm whenoneconsiderslargeandverylarge commercial farms the share of farm in come in total household income ranges from50 to 75

common persistence in conditional variances since the introduction of the autoregressive conditional heteroskedastic arch model in engle 1982 numerous applications of this modeling strategy have already appeared a common finding in many of these studies with high frequency financial or monetary data concerns the presence of an approximate unit root in the autoregressive polynomial in the univariate time series representation for the conditional second order moments of the process as in the so called integrated generalized arch igarch class of models proposed in engle and bollerslev 1986 in the igarch models shocks to the conditional variance are persistent in the sense that they remain important for forecasts of all horizons this idea is readily extended to a multivariate framework even though many time series may exhibit persistence in variance it is likely that several different variables share the same common long run component in that situation the variables are naturally defined to be co persistent in variance and the co persistent linear combination is interpretable as a long run relationship conditions for co persistence to occur in the multivariate linear garch model are presented these conditions parallel the conditions for linear co integration in the mean as developed by engle and granger 1987 the presence of co persistence has important implications for asset pricing relationships and in optimal portfolio allocation decisions an empirical example relating to the time series properties of nominal u s dollar exchange rates for the deutschemark and the british pound provides a simple illustration of the ideas

on measuring child costs with applications to poor countries the theoretical basis for measuring child costs is discussed and detailed consideration is given to two straightforward procedures for calculation engel s food share method and rothbarth s adult good method each of these methods embodies different definitions of child costs so that the same empirical evidence can generate quite different estimates depending on the method used it is shown that true costs are generally overstated by engel s method and understated by rothbarth s procedure although the latter unlike the former can provide a sensible starting point for cost measurement our estimates from sri lankan and indonesian data suggest that children cost their parents about 30 40 percent of what they spend on themselves

exchange rate volatility and u s monetary policy an arch application this paper examines the effect of shifts in u s monetary policy regimes on the stochastic process that generates foreign exchange rates to account for the observed behavior of the data record the author models nominal dollar exchange rates as univariate autoregressive conditional heteroskedastic processes he then tests the stability of this process across u s monetary policy regimes for four of the currencies in the sample accounting for regime shifts improves the fit of the model regime shifts also appear to diminish the degree of persistence of variance making it less likely that exchange rates are integrated in variance copyright 1989 by ohio state university press

determinants of land value volatility in the u s corn belt understanding land value volatility and its reaction to exogenous shocks helps land owners investors and lenders assess risk land value volatility the variance of the unpredictable component of

measuring chronic poverty without a panel abstract a new method of decomposing cross sectional poverty estimates into chronic and transient components is demonstrated using data from a recent household survey in papua new guinea this method is simpler than previously used panel methods because it does not require data on every household in every period the only requirement is that a subset of the surveyed households have a repeat observation made on their welfare indicator some time after the initial observation in the setting considered the chronic and transient components of headcount poverty are roughly equal while three quarters of the mean poverty gap is transient in the sense of being due to within year fluctuations in expenditures

poverty and household size the widely held view that larger families tend to be poorer in developing countries has influenced research and policy the scope for size economies in consumption cautions against this view we find that the correlation between poverty and size vanishes in pakistan when the size elasticity of the cost of living is about 0 6 this turns out to be the elasticity implied by a modified version of the food share method of setting scales by contrast some measures of child nutritional status indicate an elasticity of unity consideration of the weight attached to child versus adult welfare may help resolve the non robustness of demographic profiles of poverty excerpt

unemployment benefits and labor market transitions a multinomial logit model with errors in classification this paper utilizes validation data on survey response error in the current population survey to generalize the standard multinomial logit model to allow for spurious events that result from classification error the authors basic approach could be used with other stochastic models of discrete events as well they illustrate their algorithm by studying the effect of unemployment insurance on transitions from unemployment to employment and on labor force withdrawal their results confirm earlier work suggesting that unemployment insurance lengthens unemployment spells and show that correcting for classification error strengthens the apparent effect of unemployment insurance on spell durations copyright 1995 by mit press

assessing the extent and nature of chronic poverty in low income countries issues and evidence discussions of chronic poverty have mostly considered its monetary dimensions with current evidence suggesting that such poverty is much more transient than chronic but chronic poverty is a real and important phenomenon potentially more important quantitatively than it first appears once account is taken of different methodological approaches and inevitable measurement difficulties the chronic poor have distinctive characteristics such as lack of assets or high dependency rates which may account for their persistent poverty the paper argues that it is also necessary to develop concepts of chronic poverty further covering relevant nonmonetary dimensions and not just relying on panel data

the persistence in volatility of the us term premium 1970 1986 abstract this paper examines the persistence of the volatility of the risk premia for excess holding period returns of the term structure using a garch m model of the conditional variance the finding of a high degree of persistence cannot be sustained once allowance is made for a structural break in the unconditional variance caused by a change in the operation of us monetary policy during 1979 1982

volatility persistence and stock valuations some empirical evidence using garch summary in this paper issues of volatility persistence and the changing risk premium in the stock market are investigated using the garch estimation technique we get a point estimate of the index of relative risk aversion of 4 5 and confirm the existence of changing equity premiums in the us during 1962 1985 the persistence of shocks to the stock return volatility is so high that the data cannot reject a non stationary volatility process specification the results of this paper are consistent with malkiel and pindyck s hypothesis that it is the unforseen rise ini the investment uncertainty during 1974 that causes the market to plunge

parametric and semiparametric modeling of the off farm labor supply of agrarian households in transition bulgaria the reaction of labor marketsto economic reforms is an important indicator of the progress of transition because of diminished government support and the breakup of state and collective enterprises labor market adjustments in the transition economies have been particularly severe in the agricultural sector thisarticle evaluatesthe off farm labor market for a sample of agrarian households in transition bulgaria we give particular attention to the distributional assumptions that underlie standard approaches to the evaluation of labor supply a variety of specification tests are considered and support for standard maximum likelihood estimates which rely on normality as a maintained hypothesis is mixed alternative semiparametric distribution free estimators are also considered the empirical results indicate that five years after the initiation of the transition off farm labor supply patterns for bulgarian agricultural households are similar to what is commonly observed in developed market economies labor supply is positively affected by factors such as education and work experience which are hypothesized to increase off farm wages social benefit programs providing monetary or in kind support payments are shown to significantly decrease off farm work copyright 2002 oxford university press

quasi maximum likelihood estimation of multivariate probit models farm couples labor participation joint estimation of farmers farm and off farm work participation requires a multivariate probit model in which the number of equations is twice the number of household members where there are more than two such equations i suggest a quasi maximum likelihood method which requires only two levels of numerical integration the method maximizes the use of sample information given this numerical feasibility condition it is used for estimating a joint participation model of farm couples farm and off farm work the model yields conclusions about comparative advantages of men and women in farm off farm and housework which cannot be obtained with a more limited setup

linking the price of agricultural land to use values and amenities the recent appreciation in agricultural land values across the united states has raised a number of important questions for farmers farmland owners lenders and policy makers while traditional economic theory suggests that farmland values are determined by the discounted stream of expected returns previous research has shown that agricultural land values are actually driven by a complex set of factors this study leverages the unique characteristics of a national land based usda survey on farmland values and cash rents to estimate broad national level determinants of the market value of cropland and pastureland our results support past research findings that indicate farmland values are only partially explained by agricultural returns we find that multiple nonagricultural attributes of farmland also contribute to the market value

the future of farm policy analysis a household perspective farms farmers farm families and even farm policy have changed since the new deal now it is time to bring the methods of farm policy analysis and the scope of data collection up to date agricultural economics by tradition an empirical discipline can once again offer important insights into the design implementation and effectiveness of policy to succeed in this century though requires an emphasis on understanding microeconomic behavior at the farm household level

income smoothing and consumption smoothing one way that risk averse households protect consumption levels is to borrow and use insurance mechanisms another way common in low income economies is to diversify economic activities and make conservative production and employment choices households thus tend toward limiting exposure only to shocks that can be handled with available credit and insurance typically both types of mechanisms are studied independently but much more can be learned by studying them together first we obtain a more complete picture of risks costs and insurance possibilities second it opens the way to considering biases in standard tests of credit and insurance

using repeated cross sections to explore movements into and out of poverty movements in and out of poverty are of core interest to both policymakers and economists yet the panel data needed to analyze such movements are rare in this paper the authors build on the methodology used to construct poverty maps to show how repeated cross sections of household survey data can allow inferences to be made about movements in and out of poverty they illustrate that the method permits the estimation of bounds on mobility and provide non parametric and parametric approaches to obtaining these bounds they test how well the method works on data sets for vietnam and indonesia where we are able to compare our method to true panel estimates the results are sufficiently encouraging to offer the prospect of some limited basic insights into mobility and poverty duration in settings where historically it was judged that the data necessary for such analysis were unavailable

data for measuring poverty and inequality changes in the developing countries abstract how does income distribution change with economic growth i distinguish between two aspects of income distribution poverty and inequality and discuss how to measure each i then review what data we would want and what data we have on changes in poverty and inequality in different countries i conclude with suggestions on how to overcome some of the current data deficiencies

risk and farm operator labour supply this study uses a large increase in us federal crop insurance subsidies as a natural experiment to identify the importance of risk for farm operator labour supply subsidy increases induced greater crop insurance coverage which in turn reduced farmers financial risks crop insurance participation data are merged with farm level census of agriculture data from 1992 and 1997 to compare how individuals off farm labour supply changed in response to the policy induced change in insurance coverage the empirical approach controls for unobserved heterogeneity and accounts for the censored nature of the data it is found that greater insurance coverage reduces the off farm labour supply of operators who produced at least 100 000 of output and increased the labour supply of small farm operators who produced less than 25 000 of output

farm income variability and the supply of off farm labor if farmers are risk averse greater farm income variability should increase off farm labor supply this effect is confirmed for a sample of kansas farmers off farm employment of farmers and their spouses is also found to be significantly influenced by farm experience off farm work experience farm size leverage efficiency and farm specific education in addition farm operators and spouses who receive significant income support through government farm programs are less likely to work off the farm this may suggest that policy changes reducing farm income support payments may increase off farm employment of farmers and their spouses

understanding farmland price changes this paper develops a structural model of land prices which includes the multidimensional effects of inflation on capital erosion savings return erosion and real debt reduction as well as the effect of changes in the opportunity cost of capital the results show that inflation and changes in the real returns on capital are major explanatory factors in farmland price swings in addition to returns to farming additionally the effects of credit market constraints and expectations schemes are considered explicitly in the analytical model

land price volatility in a geographically dispersed market historical evidence and theory lead to a hypothesis that land price variation increases with distance to market this hypothesis is tested with county data from five cornbelt states during the period 1969 to 1987 when price changes were unusually large our data support the hypothesis in the 70s prices increased more in the western cornbelt than in the eastern cornbelt in the 80s the western cornbelt experienced the more precipitous price declines our hypothesis explains why great plains farmers have experienced greater financial problems during times of stress than have many other farmers

expected poverty under risk induced welfare variability two of the most widely accepted stylised facts about agriculture in south asia sub saharan africa and elsewhere are that income is highly uncertain from one year to another and that deep and widespread poverty exists and yet there has been very little analysis of the joint problems of poverty and risk this paper offers a methodological approach to the issue of how risk affects poverty and applies it to household level data for dry areas of rural india the following questions are addressed under what conditions can one expect an increase in the riskiness of an income or consumption stream to increase poverty how should one measure the contribution of risk to poverty and what long term benefits in terms of reduced poverty can be expected from policies aimed at stabilising incomes of the poor such policies have been widely discussed in the indian subcontinent of late and their effect on rural

arch models properties estimation and testing abstract the aim of this survey paper is to provide an account of some of the important developments in the autoregressive conditional heteroskedasticity arch model since its inception in a seminal paper by engle 1982 this model takes account of many observed properties of asset prices and therefore various interpretations can be attributed to it we start with the basic arch models and discuss their different interpretations arch models have been generalized in different directions to accommodate more and more features of the real world we provide a comprehensive treatment of many of the extensions of the original arch model next we discuss estimation and testing for arch models and note that these models lead to some interesting and unique problems there have been numerous applications and we mention some of these as we present different models the paper includes a glossary of the acronyms for the models we describe

rational expectations econometric analysis of changes in regime an investigation of the term structure of interest rates abstract this paper is of interest both for its methodological contribution of new tools for analyzing rational expectations models and for its substantive conclusions concerning the term structure of interest rates during the monetary experiment of october 1979 the paper studies systems subject to changes in regime interpreted here as occasional discrete shifts in the parameters governing the time series behavior of exogenous economic variables the specification is shown to be quite tractable both theoretically and empirically the technique is used to analyze yields on three month treasury bills and ten year treasury bonds during 1962 to 1987 a constant parameter linear model for short term rates is shown to be inconsistent both with the univariate time series properties of short rates and with the observed bivariate relation between long and short rates under the expectations hypothesis of the term structure an alternative nonlinear model that admits the possibility of changes in regime affords a much better description of the univariate process for short rates moreover the cross equation restrictions implied by the expectations hypothesis of the term structure are consistent with the nonlinear specification indeed the residuals of the restricted relation have a standard error of only 0 8 basis points this is a third less than that of a completely unrestricted linear regression of long rates on short rates and compares with an unconditional standard deviation of long rates of 142 basis points i conclude that once the recognition by bond traders of changes in regime is taken into account the expectations hypothesis of the term structure of interest rates holds up fairly well for these data

returns interest rates and inflation how they explain changes in farmland values weather in the corn belt and northern plains and the elimination of traditional commodity programs have refocused attention on farmland valuation this study uses a statistical formulation of information provided by individual regressors to examine the sensitivity of farmland values to changes in inflation returns on agricultural assets and the cost of capital the results indicate that inflation provides the most information on changes in farmland values however the regional results indicate that regions that tend to be more sensitive to changes in the return on agricultural assets also rely more heavily on government payments

issues in measuring and modeling poverty economists have relied heavily on household incomes or expenditures normalized for differences in household specific prices and demographics in their research and policy advice related to poverty and inequality recognizing the conceptual and empirical problems that confound such measures does not mean that they should be ignored instead it indicates the need for supplementary measures to capture the missing items implementing a genuinely multidimensional approach will often make the welfare rankings of social states more difficult but that fact points to the nonrobustness of low dimensional rankings this may have its own policy ramifications with the possibility of correspondence between policy instruments and welfare objectives the model types used to understand the poverty and inequity determination processes will be affected not only will there be more dependent variables to consider but variables will have potentially complex relationships these relationships will often be hard to empirically disentangle despite richer integrated and longitudinal data sets such data open rich and relevant agenda for research into the dynamics of poverty along multiple dimensions a simultaneous attack on these issues from all three fronts measurement modeling and data offers hope of establishing a credible empirical foundation for public action in fighting poverty

expectation volatility and liquidity in the housing market measuring housing price volatility is fundamental to understanding the dynamics of housing price risk this article aims to explore whether a liquidity factor plays a role in explaining the second moment i e the volatility of housing prices housing price volatility is measured as the conditional variance of a generalized auto regressive conditional heteroscedasticity garch model under the adaptive expectations framework the empirical evidence reveals that volatility transmits from smaller housing units to larger housing units which indirectly supports the trade up effect discussed in the literature in addition less liquid housing classes are more sensitive to unexpected liquidity shocks and the starter housing class is extraordinarily sensitive to negative liquidity shocks consistent with friction search theory pricing errors are alleviated as the trading volume increases because the valuation price tends to be more accurate as more information is available

the persistence of volatility and stock market fluctuations this paper examines the potential influence of changing volatility in stock market prices on the level of stock market prices it demonstrates that volatility is only weakly serially correlated implying that shocks to volatility do not persist these shocks can therefore have only a small impact on stockmarket prices since changes in volatility affect expected required rates of return for relatively short intervals these findings lead us to be skeptical of recent claims that the stock market s poor performance during the 1970 s can be explained by volatility induced increases in risk premia this abstract was borrowed from another version of this item this abstract was borrowed from another version of this item this abstract was borrowed from another version of this item this abstract was borrowed from another version of this item this abstract was borrowed from another version of this item this abstract was borrowed from another version of this item this abstract was borrowed from another version of this item this abstract was borrowed from another version of this item this abstract was borrowed from another version of this item this abstract was borrowed from another version of this item this abstract was borrowed from another version of this item this abstract was borrowed from another version of this item this abstract was borrowed from another version of this item this abstract was borrowed from another version of this item this abstract was borrowed from another version of this item this abstract was borrowed from another version of this item this abstract was borrowed from another version of this item this abstract was borrowed from another version of this item

nonlinearity breaks and long range dependence in time series models we study the simultaneous occurrence of long memory and nonlinear effects such as parameter changes and threshold effects in time series models and apply our modeling framework to daily realized measures of integrated variance we develop asymptotic theory for parameter estimation and propose two model building procedures the methodology is applied to stocks of the dow jones industrial average during the period 2000 to 2009 we find strong evidence of nonlinear effects in financial volatility an out of sample analysis shows that modeling these effects can improve forecast performance supplementary materials for this article are available online

volatility persistence in crude oil markets financial market participants and policy makers can benefit from a better understanding of how shocks can affect volatility over time this study assesses the impact of structural changes and outliers on volatility persistence of three crude oil markets brent west texas intermediate wti and organization of petroleum exporting countries opec between january 2 1985 and june 17 2011 we identify outliers using a new semi parametric test based on conditional heteroscedasticity models these large shocks can be associated with particular event patterns such as the invasion of kuwait by iraq the operation desert storm the operation desert fox and the global financial crisis as well as opec announcements on production reduction or us announcements on crude inventories we show that outliers can bias i the estimates of the parameters of the equation governing volatility dynamics ii the regularity and non negativity conditions of garch type models garch igarch figarch and hygarch and iii the detection of structural breaks in volatility and thus the estimation of the persistence of the volatility therefore taking into account the outliers on the volatility modelling process may improve the understanding of volatility in crude oil markets

determinants of housing price volatility in canada a dynamic analysis this article tries to identify the determinants of housing price volatility and to examine the dynamic effects of these determinants on volatility using quarterly data for canada the generalized autoregressive conditional heteroskedastic garch and the vector autoregressive var models have been employed to analyse possible time variation of the housing price volatility and the interactions between the volatility and the key macroeconomic variables we find the evidence of time varying housing price volatility for canada our var granger causality and variance decomposition vdc analyses demonstrate that housing price volatility is affected significantly by gross domestic product gdp growth rate housing price appreciation rate and inflation on the other hand volatility affects gdp growth rate housing price appreciation and volatility itself the impulse response analysis reveals the asymmetric of the positive and negative shocks the findings of this article have important implications particu

are farmers decisions to work off the farm related to their decisions to participate in the conservation reserve program since both working off the farm and participating in the conservation reserve program crp remove important resources from us agricultural production we utilize two econometric specifications to test hypotheses regarding whether these two decisions by farmers are independent we find statistical evidence that decisions to participate in crp and work off the farm are correlated characteristics of farm households and farm operations affect both decisions directly and indirectly as do local economic conditions and participation in other farm programs to illustrate their importance we simulate the combined direct and indirect effects of changes in decoupled payments and farm size on the probabilities of farm households engaging in these two activities we also illustrate that the probability of engaging in these two activities depends on whether the farm is located in a state or local agricultural district or participates in a related farmland retention program

structural adjustment policies income distribution and poverty a review of the jamaican experience abstract although jamaica has had structural adjustment and standby loans from the world bank and the international monetary fund imf since 1977 the implementation of typical structural adjustment policies such as trade and financial liberalization privatization and labor market reform has for the most part occurred only since 1989 during 1989 1993 when the jamaican economy underwent the most drastic liberalization policies inequality and poverty declined although there were sharp jumps in both inequality and poverty in 1991 when financial liberalization occurred the overall decline in poverty is attributed to the strong performance of domestic agriculture and the increased inflow of remittances and seems unlikely to be sustained

chronic and transient poverty in rural china abstract this paper rectifies the poverty decomposition framework of rodgers and rodgers 1993 which violates the focus axiom of sen 1976 an empirical application of the rectified technique reveals that poverty in rural china was dominated by the chronic component

modeling and forecasting the volatility of petroleum futures prices we investigate volatility models and their forecasting abilities for three types of petroleum futures contracts traded on the new york mercantile exchange west texas intermediate crude oil heating oil 2 and unleaded gasoline and suggest some stylized facts about the volatility of these futures markets particularly in regard to volatility persistence or long memory properties in this context we examine the persistence of market returns and volatility simultaneously using the following arfima garch class models arima garch arfima garch arfima igarch and arfima figarch although the arfima figarch model better captures long memory properties of returns and volatility the out of sample analysis indicates no unique model for all three types of petroleum futures contracts suggesting that investors should be careful when measuring and forecasting the volatility risk of petroleum futures markets

sudden changes in variance and time varying hedge ratios abstract this paper analyzes the influence of sudden changes in the unconditional volatility on the estimation and forecast of volatility and its impact on futures hedging strategies we employ several multivariate garch models to estimate the optimal hedge ratios for the spanish stock market including in each one some well known patterns that may affect volatility forecasts asymmetry and sudden changes the main empirical results show that more complex models including sudden changes in volatility outperform the simpler models in hedging effectiveness both with in sample and out of sample analysis however the evidence is stronger when the loss distribution tail is used as a measure for the effectiveness value at risk var and expected shortfall es suggesting that traditional measures based on the variance of the hedged portfolio should be used with caution

forecasting volatility and volume in the tokyo stock market long memory fractality and regime switching abstract we investigate the predictability of both volatility and volume for a large sample of japanese stocks the particular emphasis of this paper is on assessing the performance of long memory time series models in comparison to their short memory counterparts since long memory models should have a particular advantage over long forecasting horizons we consider predictions of up to 100 days ahead in most respects the long memory models arfima figarch and the recently introduced multifractal model dominate over garch and arma models however while figarch and arfima also have quite a number of cases with dramatic failures of their forecasts the multifractal model does not suffer from this shortcoming and its performance practically always improves upon the naive forecast provided by historical volatility as a somewhat surprising result we also find that for figarch and arfima models pooled estimates i e averages of parameter estimates from a sample of time series give much better results than individually estimated models

the complex dynamics of smallholder technology adoption the case of sri in madagascar this article explores the dynamics of smallholder technology adoption with particular reference to a high yielding low external input rice production method in madagascar we present a simple model of technology adoption by farm households in an environment of incomplete financial and land markets we then use a probit model and symmetrically censored least squares estimation of a dynamic tobit model to analyze the decisions to adopt expand and disadopt the method we find that seasonal liquidity constraints discourage adoption by poorer farmers learning effects both from extension agents and from other farmers exert significant influence over adoption decisions

persistence in variance structural change and the garch model this article examines the persistence of the variance as measured by the generalized autoregressive conditional heteroskedasticity garch model in stock return data in particular we investigate the extent to which persistence in variance may be overstated because of the existence of and failure to take account of deterministic structural shifts in the model both an analysis of daily stock return data and a monte carlo simulation experiment confirm the hypothesis that garch measures of persistence in variance are sensitive to this type of model misspecification

how relevant is volatility forecasting for financial risk management it depends if volatility fluctuates in a forecastable way volatility forecasts are useful for risk management hence the interest in volatility forecastability in the risk management literature volatility forecastability however varies with horizon and different horizons are relevant in different applications moreover existing assessments of volatility forecastability are plagued by the fact that they are joint assessments of volatility forecastability and an assumed model and the results can vary not only with the horizon but also with the assumed model to address this problem we develop a model free procedure for assessing volatility forecastability across horizons perhaps surprisingly we find that volatility forecastability decays quickly with horizon volatility forecastability although clearly of relevance for risk management at the short horizons relevant for say trading desk management may be much less important at longer horizons

modelling the conditional volatility of commodity index futures as a regime switching process commodity index futures offer a versatile tool for gaining different forms of exposure to commodity markets volatility is a critical input in many of these applications this paper examines issues in modelling the conditional variance of futures returns based on the goldman sachs commodity index gsci given that commodity markets tend to be choppy webb 1987 a general econometric model is proposed that allows for abrupt changes or regime shifts in volatility transition probabilities which vary explicitly with observable fundamentals such as the basis garch dynamics seasonal variations and conditional leptokurtosis the model is applied to daily futures returns on the gsci over 1992 1997 the results show clear evidence of regime shifts in conditional mean and volatility once regime shifts are accounted for garch effects are minimal consistent with the theory of storage returns are more likely to switch to the high variance state when the basis is negative than when the basis is positive the regime switching model also performs well in forecasting the daily volatility compared to standard garch models without regime switches the model should be of interest to sophisticated traders who base their trading strategies on short term volatility movements managed commodity funds interested in hedging an underlying diversified portfolio of commodities and investors of options and other derivatives tied to gsci futures contracts copyright 2001 john wiley sons ltd

heteroskedasticity in stock return data volume versus garch effects this paper provides empirical support for the notion that autoregressive conditional heterqskedasticity arch in daily stock return data reflects time dependence in the process generating information flow to the market daily trading volume used as a proxy for information arrival time is shown to have significant explanatory power regarding the variance of daily returns which is an implication of the assumption that daily returns are subordinated to intraday equilibrium returns furthermore arch effects tend to disappear when volume is included in the variance equation the autoregressive conditiqnal heteroskedasticity arch process of engle 1982 has been shown to provide a good fit for many financial return time series 1 arch imposes an autoregressive structure on conditional variance allqwing volatility shocks to persist over time this persistence captures the propensity of returns of like magnitude to clu ter in time and can explain the well documented nonnormality and nonstability of empirical asset return distributions see especially fama 1965 an appealing explanation for the presence of arch is based upon the hypothesis that daily returns are generated by a maiture of distributions in which the rate of daily information arrival is the stochastic mixing variable as suggested by diebold 1986 gallant hsieh and tauchen 1988 and stock 1987 1988 arch might capture the time series properties e g serial correlation of this mixing variable hqwever this linkage has not been broadly documented with the datia the objective of this study is to examine the validity of this explanation for daily stock returns the empirical strategy exploits the implication of the mixture model that the variance of daily price increments is heteroskedastic specifically positively related to the rate of daily information arrival using daily trading volume as a proxy for the mixing variable we show that for a sample of 20 common stocks arch effects vanish when volume is included as an explanatory variable in the conditional variance equation