does a blue revolution help the poor evidence from bangladesh the rapid growth in aquaculture production globally and in bangladesh is well documented over 2000 2010 per capita production of aquaculture grew 76 while the consumer price of fish declined 45 previous studies have suggested pro poor effects of aquaculture based on fish production and consumption patterns this study attempts to quantify the contribution of aquaculture to income growth and poverty reduction in bangladesh using household survey data and a microsimulation approach based on an expanded version of deaton s concept of net benefit ratio we estimate that aquaculture s contribution to income growth between 2000 and 2010 was 2 1 including both price and quantity effects this income growth was translated into poverty reduction of 1 7 percentage points although these estimates seem small they represent almost 10 of the overall poverty reduction in bangladesh during the first decade of the 21st century put differently of the 18 million bengalis who escaped poverty during 2000 2010 about 1 8 million of them managed to do so because of the rapid growth in aquaculture which contributed to rural income while making fish more accessible to consumers

does size matter reassessing the relationship between aquaculture and poverty in bangladesh abstract aquaculture has long been promoted by development institutions in bangladesh on the understanding that it can alleviate poverty most of this attention has focused on forms of the activity commonly referred to as small scale this article draws on concepts from the literature on agricultural growth and elaborates a typology of aquaculture based on relations of production which suggests that in bangladesh quasi capitalist forms of aquaculture may possess greater potential to reduce poverty and enhance food security than the quasi peasant modes of production generally assumed to do so the implications of this conclusion are explored

who suffers the penalty a panel data analysis of earnings gaps in vietnam in spite of its predominant economic weight in developing countries little is known about the informal sector earnings structure compared to that of the formal sector taking advantage of the rich vhlss dataset in vietnam in particular its three wave panel data 2002 2004 2006 we assess the magnitude of various formal informal earnings gaps while addressing heterogeneity at three different levels the worker the job wage employment vs self employment and the earnings distribution we estimate fixed effects and quantile regressions to control for unobserved individual characteristics our results suggest that the informal sector earnings gap highly depends on the workers job status and on their relative position in the earnings distribution penalties may in some cases turn into premiums by comparing our results with studies in other developing countries we draw conclusions highlighting vietnam s labour market specificity

the gender wage gap in three african countries this study examined the size and determinants of the gender wage gap in ethiopia uganda and the ivory coast the analysis includes decomposition of wage differences and sector decomposition by gender using oaxaca and neumark methods data were obtained from the 1990 survey of adolescent fertility reproductive behavior and employment status of youth in urban ethiopia the 1985 1986 and 1987 ivory coast living standards surveys and the 1992 integrated survey of uganda the samples were restricted to urban population the sample population was aged 15 59 in the ivory coast and uganda and 15 30 years in ethiopia the analysis focused on uncorrected estimates index problems that were encountered in uganda suggest caution in drawing inferences decomposition varied widely across the 3 countries there were substantial gender wage differences in uganda and ethiopia which are attributed to wage generating characteristics neumark interpretations suggest that favoritism of men and discrimination against women were equally important in ethiopia while discrimination against women was key in uganda gaps by sector were wider in the private sector in ethiopia comparable in uganda and wider in the public sector in the ivory coast the processes that accounted for sector wage gaps by gender varied between countries the wage gap appears narrower in descriptive statistics which shows that women were overrepresented in the better paid public sector the gender gaps in ethiopia and ivory coast would be 17 and 20 greater respectively if men and women were equally allocated by sector in uganda sector equity would increase the gap by 5

the returns to schooling a selectivity bias approach with a continuous choice variable the essence of selection bias is that we do not observe nonoptimal choices this applies whether the choice variable is discrete or continuous this paper extends the selection bias methodology to the case where the choice variable is continuous and the choice set is ordered the leading practical application of this analysis is the schooling choice problem schooling is treated as a continuous choice variable and selectivity corrected rates of return are estimated the findings suggest selectivity is of considerable importance and support the comparative advantage hypothesis of willis and rosen 18

some results in the theory of arbitrage pricing this paper derives a stronger version of huberman s recent preference free pricing theorem this pricing result relates the expected return on an asset to its factor responses and the covariance structure of the residuals from a linear factor model it must characterize any infinite asset economy in which no arbitrage opportunities are present whether or not the factor model has uncorrelated residuals this result provides the intuition for the role of residual risk in the pricing model and eliminates some classes of arbitrage opportunities still present under huberman s bound some applications to empirical tests and performance measurement are also discussed the arbitrage pricing theory is one of several financial pricing models which attempts to explain the cross sectional variation in expected returns on assets in certain respects it is similar to the capital asset pricing model but there are both substantive and subtle differences one of the key advantages of the apt is that it derives a simple linear pricing relation approximating that in the capm without some of the latter s objectionable assumptions perhaps the key disadvantage of the apt is that it provides no clues as to what might be important factors nor as to how to interpret the factor premiums which appear in the pricing equation this paper serves several purposes after reviewing the linear factor model formulation in section i it derives in section ii a stronger version of huberman s 9 recent preference free pricing theorem this pricing result relates the expected return on an asset to its factor responses and the covariance structure of the residuals this relation must characterize any infinite asset economy in which no arbitrage opportunities are present whether or not a linear factor model with uncorrelated residuals is the appropriate returns generating mechanism section iii specializes this result by eliminating the effects of residual covariances and compares the results here to those of previous apt models when applied to the standard linear factor model with uncorrelated residuals this new pricing bound eliminates arbitrage opportunities which remain under huberman s bound this result also provides for the first time the intuition for the role of residual risk in the approximate pricing relation section v provides an interpretation of the factor premiums and gives a valid asset pricing model interpretation to the apt which is consistent with merton s

dynamic models for fixed income portfolio management under uncertainty abstract we develop multi period dynamic models for fixed income portfolio management under uncertainty using multi stage stochastic programming with recourse the models integrate the prescriptive stochastic programs with descriptive monte carlo simulation models of the term structure of interest rates extensive validation experiments are carried out to establish the effectiveness of the models in hedging against uncertainty and to assess their performance vis a vis single period models an application to tracking the salomon brothers mortgage index is reported with very encouraging results results that establish the efficacy of the models in hedging against out of sample scenarios are also reported for an application from money management the multi period models outperform classical models based on portfolio immunization and single period models

hedonic wages and labor market search this article investigates the consequences of labor market search for the theory of hedonic wages we find that the introduction of search has surprising consequences for the theory of hedonic wages in particular we demonstrate that the equilibrium distribution of wage and nonwage amenity bundles generally bears little resemblance to workers underlying preferences a consequence of this analysis is that estimates of workers marginal willingness to pay derived from the conventional hedonic wage methodology are biased in addition we demonstrate that search generates differences between firm level and employee level data that can cause substantial deviations in the estimates of hedonic wage equations

improving developing country food security through aquaculture development lessons from asia abstract this paper provides a framework for examining aquaculture s linkages to food and nutritional security by elucidating key hypotheses concerning the role of aquaculture in household food and income systems in developing countries taking examples from developing asia where aquaculture showed a steady growth over the last decade the implications of aquaculture development are examined from the standpoint of its impact on employment income and consumption analysis revealed clear evidence of positive income and consumption effects of aquaculture on households however employment effects are still not significant the context of targeting small scale and subsistence oriented farmers as a means of improving food security in the developing countries has also been analyzed by identifying key socio economic and policy factors affecting aquaculture adoption and its impact on the poor the paper concludes that national policies for aquaculture development will need to concurrently address the food security and poverty questions more sharply than has been done at present by providing institutional and infrastructure support for access to resources such as land and water and to markets by poor households finally more empirical evidence should be collected on the varied opportunities aquaculture would provide to improve the income employment and food consumption levels within households

note a note on the use of the capm as a strategic planning tool a recent paper by naylor and tapon naylor thomas h francis tapon 1982 the capital asset pricing model an evaluation of its potential as a strategic planning tool management sci 28 1166 1173 showed that the capital asset pricing model capm can be an important strategic planning tool but their specific strategic suggestions were incorrect the proper conclusion to draw from the capm is that a company should purchase a business if its expected return exceeds the expected return in equilibrium of a business in the same risk class in the absence of synergy each potential acquisition should be evaluated on its own merit independent of the other businesses in a company s portfolio when all firms are in equilibrium no gain may be made from merger or takeover

farming fish for profits a small step towards food security in sub saharan africa abstract in addition to volatile fluctuations due to seasonal or regional factors food security has two main components access and availability this paper presents a diagrammatical model to indicate how aquaculture particularly private sector aquaculture can contribute to these components of food security in sub sahara africa food accessibility is increased when commercial aquaculture generates employment without such employment the poor might never translate their need for food into effective demand food availability is increased either immediately when aquaculture output is sold in the domestic market or later when the foreign exchange earned from aquaculture exports is used to import food this paper does not argue that commercial aquaculture will eliminate poverty within sub sahara africa the sector is too marginal however it can be one small step among others moreover driven by the private sector commercial aquaculture does not need onerous public or donor funding it therefore should not be ignored by policy makers at the local level the impact on communities can be dramatic this is illustrated in the kariba area of zimbabwe where commercial tilapia farms provide jobs and incomes in an impoverished region these incomes enable workers and their families to purchase food in addition the farms supply the local population with whole fish and fish heads which are a source of protein some policy options are suggested to promote private investment in the sector with an emphasis on polices that incur few government expenditures

evidence on the glass ceiling effect in france using matched worker firm data in this article we investigate the relevance of the glass ceiling hypothesis in france according to which there exist larger gender wage gaps at the upper tail of the wage distribution using a matched worker firm data set of about 1 30 000 employees and 14 000 employers we estimate quantile regressions and rely on a principal component analysis to summarize information specific to the firms our different results show that accounting for firm related characteristics reduces the gender earnings gap at the top of the distribution but the latter still remains much higher at the top than at the bottom furthermore a quantile decomposition shows that the gender wage gap is mainly due to differences in the returns to observed characteristics rather than in differences in characteristics between men and women

estimating the demand for calories in india this article examines the long run relationship between per capita calorie intake per capita income and food prices using aggregate data for india 1961 1992 cointegration analysis yields an income elasticity of calorie intake of 0 34 while the food price elasticity is insignificant thus economic growth in india as measured by increasing per capita income has significantly improved calorie intake future income growth can alleviate further inadequate nutrition however significant improvements in calorie intake cannot be made directly by food subsidies a further result is that calorie intake is granger caused by income and not vice versa income generation is unconstrained by calorie intake

a dynamic bank portfolio planning model with multiple scenarios multiple goals and changing priorities abstract the paper discusses a practical application of a two stage linear goal programming model to the management of the domestic and foreign currency denominated assets and liabilities of a large bank in finland the planning horizon includes three one year planning periods a number of alternative scenarios are used to describe uncertainty concerning future developments in these periods the scenarios are related to general economic conditions as well as the state of the domestic and foreign financial markets the bank is assumed to have multiple conflicting goals with different and changing priorities the goals deal with expected profits risk liquidity capital adequacy growth customer relationships and several other aspects of the bank s operations

misspecification of capital asset pricing this study documents empirical anomalies which suggest that either the simple one period capital asset pricing model capm is misspecified or that capital markets are inefficient in particular portfolios based on firm size or earnings price e p ratios experience average returns systematically different from those predicted by the capm furthermore the abnormal returns persist for at least two years this persistence reduces the likelihood that these results are being generated by a market inefficiency rather the evidence seems to indicate that the equilibrium pricing model is misspecified however the data also reveals that an e p effect does not emerge after returns are controlled for the firm size effect the firm size effect largely subsumes the e p effect thus while the e p anomaly and value anomaly exist when each variable is considered separately the two anomalies seem to be related to the same set of missing factors and these factors appear to be more closely associated with firm size than e p ratios

a new approach to testing asset pricing models the bilinear paradigm we propose a new approach to estimating and testing asset pricing models in the context of a bilinear paradigm introduced by kruskal 18 this approach is both simple and at the same time quite general as an illustration we apply it to the special case of the arbitrage pricing model where the number of factors is pre specified the data appear to be generally in conflict with a five or seven factor representation of the model used by roll and ross 30 when we consider the number of replications of our test and the large number of observations on which it is performed the frequency with which we reject the three factor apm does not lead us to conclude that this model is unrepresentative of security returns further the rejection of the five and seven factor versions is to be expected if the three factor version is correct the paradigm gives insight into the appropriate specification of the model and suggests that there may be a small number of economy wide factors that affect security returns tests of asset pricing models on the basis of observed stock market data have represented a staple of the financial economics literature of the past twenty years the early work is reviewed in the famous paper by jensen 12 and papers by fama and macbeth 6 rosenberg and marathe 31 and roll and ross 30 there has been a great deal of confusion regarding what testable propositions are implied by these models see discussion in roll 29 in this paper we show that at a minimum all asset pricing models yet proposed imply a simple easily testable hypothesis which we refer to as the bilinear hypothesis while specific models may imply further testable propositions if the bilinear hypothesis is rejected the model is inconsistent with the data and should be rejected our test exploits the fact that the economic content of any equilibrium asset pricing model can be expressed in the form of a potentially refutable constraint on the set of parameters of the process generating security returns this constraint specifies that given a set of security specific characteristics there exists a linear relationship common across securities relating expected returns to these

how many stocks make a diversified portfolio we show that a well diversified portfolio of randomly chosen stocks must include at least 30 stocks for a borrowing investor and 40 stocks for a lending investor this contradicts the widely accepted notion that the benefits of diversification are virtually exhausted when a portfolio contains approximately 10 stocks we also contrast our result with the levels of diversification found in studies of individuals portfolios

compensating wage differentials and shift work preferences we study if there are compensating wage differentials paid for shift work using french matched employer employee data for male full time blue collar workers there is a significant shift premium of 16 that has a significant impact on shift work choice

rethinking aquaculture for resource poor farmers perspectives from bangladesh expectations about the unfulfilled potential of aquaculture as a source of animal protein for the poor of bangladesh are currently running high evidence suggests that social and economic constraints to intensification are as yet poorly understood and may constitute an important barrier to improving resource utilisation both public sector agencies and ngos are currently engaged in a range of aquaculture initiatives this paper critically surveys a selection of ongoing aquaculture research and extension programmes it is suggested that current approaches are unlikely to benefit those with low incomes in bangladesh since there are problems with both the conceptualisation of the problem of aquaculture and the types of institutional arrangements being deployed to tackle it the paper ends with several recommendations about future priorities in terms of the nature and style of aquaculture research

factor pricing in a finite economy abstract prior theoretical derivations of the arbitrage pricing theory apt bound an aggregate measure of the deviation of mean asset returns from that predicted by a linear pricing equation it is conceivable given this bound that some assets might be badly mispriced by the model in this paper a more intuitive derivation of the factor pricing equation is presented which describes the deviation on an asset by asset basis the deviation is shown to be small for assets in a realistic finite economy and is arbitrarily close to zero for those assets with arbitrarily small size relative to aggregate wealth it follows that the linear pricing equation provides a good approximation for the mean returns of all traded assets

the economic value of stock and call options on the swedish financial market abstract the intense trading activity and the very existence of organized stock option markets suggest that these financial contracts provide noticeable economic benefits as compared to trades on the stock market in this paper we test the efficiency of recursive optimization strategies on a combined portfolio of stocks and call options series listed on the swedish stock market for comparison the same recursive optimization is performed on a portfolio purely consisting of stocks the portfolio efficiency of the recursive optimization strategy is also compared to results obtained with call options using a black scholes strategy

some empirical tests of the theory of arbitrage pricing we estimate the parameters of ross s arbitrage pricing theory apt using daily return data during the 1963 78 period we compare the evidence on the apt and the capital asset pricing model capm as implemented by market indices and find that the apt performs well the theory is further supported in that estimated expected returns depend on estimated factor loadings and variables such as own variance and firm size do not contribute additional explanatory power to that of the factor loadings

vector forecasting and dynamic portfolio selection empirical efficiency of recursive multiperiod strategies abstract in the paper we present a dynamic portfolio selection system the system combines recent results from the domains of time series analysis portfolio theory and multiperiod linear programming under uncertainty the performance of the decision support system is tested empirically against a dynamic super criterion defined in the study we demonstrate that suitable combination of ex ante and ex post information with initial balances for the planning horizon yields better portfolio efficiency through time than a strategy relying purely on ex ante information the system was programmed on abo academy s vax 8800 computer mainly in fortran with access to the imsl library and ifps optimum

a simple approach to arbitrage pricing theory the following sections are included introductionarbitrage pricingdiscussionreferencesdiscussion notes on the arbitrage pricing theorypure arbitrage pricing theoryapproximate arbitrage and the aptapproximate factor modelsthe competitive equilibrium version of the aptconclusionnotereferences this abstract was borrowed from another version of this item

a new linear programming approach to bond portfolio management this paper derives and tests a new linear programming lp approach to bond portfolio management the model elicits possible tax clientele effects in the pricing of u s gov ernment coupon bonds and simultaneously derives the optimal tax specific bond portfolio analytically the model derives these results by exploiting for a given tax bracket the price differential of an after tax stream of cash flows it accomplishes this objective by purchasing at the ask price underprieed bonds for the specific tax bracket while sim ultaneously selling at the bid price overpriced bonds the model requires that the net cash flow inclusive of purchased and sold bonds be nonnegative at all future dates the problem s formulation standardizes the position taken in each bond to a maximum of one unit one of the model s appealing features is the parsimonious number of required calcu lations only one lp program need be run per tax bracket in addition to obtaining an optimally chosen tax specific bond portfolio the model also measures the after tax term structure of spot u s government interest rates for both tax exempt and taxable investors finally the superior monthly holding period rates of return on the optimal taxspecific bond portfolio demonstrate an important property ofthe model s output

cost of capital to the hospital sector this paper provides estimates of the cost of equity and debt capital to for profit and non profit hospitals in the u s for the years 1972 83 the cost of equity is estimated using alternatively the capital asset pricing model and arbitrage pricing theory we find that the cost of equity capital using either model substantially exceeded anticipated inflation the cost of debt capital was much lower accounting for the corporate tax shield on debt and capital paybacks by cost based insurers lowered the net cost of capital to hospitals

the quality of employment qoe in nine latin american countries a multidimensional perspective abstract this paper proposes a methodology for measuring the quality of employment from a multidimensional and public policy perspective in latin american developing countries argentina bolivia brazil chile colombia ecuador mexico paraguay peru and uruguay using household and labour force survey data from 2015 the purpose of this paper is to demonstrate that the qoe can be measured using a multidimensional methodology that can inform policy makers about the state of their labour markets in a way that complements traditional variables such as participation or unemployment rates which are not always good indicators of labour market performance in developing countries with large informal sectors building on the framework of the capability approach as well as on previous work on multidimensional poverty we use the alkire foster af method to construct a synthetic indicator of the quality of employment qoe at an individual level we select three dimensions that must be considered as both instrumentally and intrinsically important to workers and the functions and capabilities generated by their employment situation income job security and employment conditions job security is then divided into two sub dimensions occupational status and job tenure as is employment conditions social security affiliation and excessive working hours a threshold is then established within each dimension and sub dimension to determine whether a person is deprived or not within each dimension before establishing an overall cut off line and calculating composite levels of deprivation the results generated by this indicator are first highly relevant to policy makers as they allow for the precise identification of groups of vulnerable workers as well as of dimensions and indicators which contribute to deprivation in the labour market second they extend the debate about employment in developing countries to variables not commonly considered by the literature as being critical to the well being of workers and their dependents such as occupational status and job tenure third this paper highlights important difference between latin american countries both in terms of the overall qoe index result as well as its component dimensions while chile presents the best results in the region paraguay presents the worst followed by mexico bolivia and peru however chile peru columbia and brazil for example have the biggest problem with job rotation finally the paper highlights that low rates of unemployment are not necessarily related to low rates of deprivation in terms of the qoe in fact in some countries analysed e g mexico the opposite is true

contribution of fisheries and aquaculture to food security and poverty reduction assessing the current evidence following a precise evaluation protocol that was applied to a pool of 202 articles published between 2003 and 2014 this paper evaluates the existing evidence of how and to what extent capture fisheries and aquaculture contribute to improving nutrition food security and economic growth in developing and emergent countries in doing so we evaluate the quality and scientific rigor of that evidence identify the key conclusions that emerge from the literature and assess whether these conclusions are consistent across the sources the results of the assessment show that while some specific topics are consistently and rigorously documented thus substantiating some of the claims found in the literature other areas of research still lack the level of disaggregated data or an appropriate methodology to reach consistency and robust conclusions more specifically the analysis reveals that while fish contributes undeniably to nutrition and food security the links between fisheries aquaculture and poverty alleviation are complex and still unclear in particular national and household level studies on fisheries contributions to poverty alleviation lack good conceptual models and produce inconsistent results for aquaculture national and household studies tend to focus on export value chains and use diverse approaches they suggest some degree of poverty alleviation and possibly other positive outcomes for adopters but these outcomes also depend on the small scale farming contexts and on whether adoption was emergent or due to development assistance interventions impacts of fish trade on food security and poverty alleviation are ambiguous and confounded by a focus on international trade and a lack of consistent methods the influences of major drivers decentralization climate change demographic transition are still insufficiently documented and therefore poorly understood finally the evaluation reveals that evidence based research and policy narratives are often disconnected with some of the strongest and long lasting policy narratives lacking any strong and rigorous evidence based validation building on these different results this paper identifies six key gaps facing policy makers development practitioners and researchers

optimality of myopic strategies for multi stock discrete time market with management costs the paper studies multi stock discrete time market models with serial correlations and with some management costs we found a market structure that ensures that the optimal strategy is myopic for the case of either power or log utility function

give a man a fishpond modeling the impacts of aquaculture in the rural economy abstract the rapid growth of fish farming over the past three decades has generated heated debate over the role of aquaculture in rural development and poverty reduction central to these debates is the question of whether and how aquaculture impacts local incomes and employment yet little empirical evidence exists on the issue to address this question we propose a local economy wide impact evaluation lewie model which nests fish farm models within a general equilibrium model of their local economy the model is calibrated using primary data collected from 1102 households in myanmar s main aquaculture zone representative of 60 of the country s aquaculture farms using this model we examine the impact of aquaculture on the incomes and labor market outcomes of fish farming households but also crop farms and non farm households in the cluster simulating one acre increases in pond plot surface we find that 1 aquaculture generates much higher incomes per acre than agriculture 2 aquaculture generates larger income spillovers than agriculture for non farm households by way of retail and labor markets 3 small commercial fish farms generate greater spillovers than large fish farms these results bolster the notion that fish farming and in particular small scale commercial aquaculture may have a significant role to play in rural development and poverty reduction

general factor models and the structure of security returns based on markowitz s pioneering study 40 sharpe 56 and lintner 38 advanced the first positivist formulations of the capital asset pricing model capm their models were subsequently refined by mossin 45 fama 15 black 1 and others even though the capm has been studied extensively it has not been empirically validated according to roll 48 the capm cannot be tested in an unambiguous fashion because of a number of intractable measurement and computational difficulties and the joint nature of the hypotheses to be tested

employment vulnerability and earnings in urban west africa this article develops indicators of vulnerability in employment in seven economic capitals of west africa and studies their links with individual incomes quantitative distributional and qualitative analyses show that vulnerability compensating mechanism is mainly seen in the informal sector in the upper tail of the earnings distribution and particularly in the circumstance of visible underemployment employment vulnerability is not compensated for the poorest workers in the private sector long job queues and weak institutional protection of workers may have reduced bargaining power in the formal sector

wage differentials employer size and unemployment the unique equilibrium solution to a game in which a continuum of individual employers choose permanent wage offers and a continuum of workers search by sequentially sampling from the set of offers is characterized wage dispersion is a robust outcome provided that workers search while employed as well as when unemployed the unique nondegenerate equilibrium distribution of wage offers is constructed for three cases 1 identical workers and employers 2 identical employers and an atomless distribution of worker supply prices and 3 identical workers and an atomless distribution of job productivities copyright 1998 by economics department of the university of pennsylvania and the osaka university institute of social and economic research association

a super criterion for testing portfolio efficiency empirical evidence on finnish stock data abstract in this paper a markovian super criterion is formulated for testing the portfolio efficiency of competing capital market theories the portfolio efficiency of the arbitrage pricing theory apt and the capital asset pricing model capm is tested on finnish weekly price index data over the 1970 1983 time frame the efficiency test results imply that the apt dominates the capm a considerable deviation between the expected pareto frontier and the best expectational frontier according to the apt is observed

is aquaculture pro poor empirical evidence of impacts on fish consumption in bangladesh summary aquaculture is widely held to contribute to poverty reduction and food security in the global south but robust evidence is limited using nationally representative data from bangladesh this study analyses changes in fish consumption from 2000 to 2010 rapid expansion of commercial aquaculture pegged down fish prices resulting in increased fish consumption by extreme poor and moderate poor consumers and those in rural areas these outcomes are closely linked to the pro poor nature of national economic growth during this period these findings contribute to a broadening of the debate on whether the growth of aquaculture in bangladesh has been pro poor