you can t save alone commitment in rotating savings and credit associations in kenya abstract this article examines one reason why individuals develop and maintain local level financial savings organizations known as rotating savings and credit organizations or roscas economic theories suggest that individuals form roscas to finance the purchase of a lumpy durable good in response to intrahousehold conflict over savings or to provide themselves with insurance the article proposes an additional hypothesis for rosca participation saving requires discipline and some roscas may be formed to provide a collective mechanism for commitment in the presence of time inconsistent preferences data from 70 roscas located in western kenya indicate that the commitment hypothesis is plausible and broadly consistent with the design and patterns of participation in these roscas as many rosca participants put it you can t save alone

beyond the stern review lessons from a risky venture at the limits of the cost benefit analysis this paper argues that debates amongst economists triggered by the stern review are partly relevant focusing on key parameters translating real ethical issues and partly misplaced in that they do not consider enough other determinants of climate change damages i the specifications of the utility function used for the assessments preference for the environment preference for smooth growth paths ii the interplay between uncertainty and the sequentiality of the decision and iii whether the growth engines behind the integrated assessment models can account for transient disequilibrium and sub optimality we derive some suggestions for any future research agenda in integrated assessment modelling whatever the position of the analysts about the relevance of the intertemporal optimisation framework and the bayesian approach to uncertainty in the climate affair

the national and international impacts of coal to gas switching in the chinese power sector abstract we evaluate the national and international impacts on energy consumption and production trade and economic activity of chinese coal to gas switching in the electric power sector we find that assumptions about growth rates in electricity generation from renewables are the key determinant in evaluating the economic consequences for coal to gas switching in china the ability to supplement natural gas generation with renewables leads to smaller reductions in chinese and global economic activity than the alternatives

the changing climate of climate change economics climate change economics is now four decades old much of what it has achieved as a field of academic enquiry can be linked back to issues of integrated assessment modelling this paper shows that the standard approach is going through a major change in scope as of the last five years the conventional focus on determining optimal mitigation paths based on modelling the social cost of carbon is being enlarged to embrace promising new waves of research these are 1 the economics of insurance against catastrophic risks 2 the economics of trade and climate and 3 the economics of climate change adaptation the paper helps to bridge the gap between economics and climate policy by showing that the analytical toolkit of climate change economics has shifted towards more realistic representations of climatic policy

on the demand for natural gas in urban china abstract using a set of unbalanced panel data for chinese s cities during the period of 2006 2009 this study aims to estimate the price and income elasticities of residential demand for natural gas natural gas consumption is specified as a function of its own price substitute prices urban wages and other supply climate and housing characteristics using a feasible generalised least squares fgls technique which controls for panel heteroskedasticity and panel correlation we find that natural gas consumption is price elastic and income inelastic when other covariates e g the supply of natural gas pipeline and heating degree days are controlled in addition there are large variations in demand behaviours across china s regions there is a substantial income effect on demand for natural gas in southern china whereas the northern regions are found to have a higher price effect in addition the substitution effect between coal and natural gas is significant in north china but is not significant in south china these findings have several important policy implications for natural gas pricing and supply cost analysis in the context of china

quasi hyperbolic discounting and retirement abstract some people have self control problems regularly this paper adds endogenous retirement to laibson s quasi hyperbolic discounting savings model quarterly journal of economics 112 1997 443 477 earlier selves think that the deciding self tends to retire too early and may save less to induce later retirement still earlier selves may think the pre retirement self does this too much saving more to induce early retirement the consumption pattern may be different from that with exponential discounting other observational non equivalence includes the impact of changing mandatory retirement rules or work incentives on savings and a possibly negative marginal propensity to consume out of increased future earnings naive agents are briefly considered

the demand for coal among china s rural households estimates of price and income elasticities abstract china s residential sector has experienced rapid electrification and gasification among rural households however coal still accounts for a large share of energy use especially in the north use of coal for cooking and heating brings large health and pollution risks from a theoretical viewpoint economic tools such as taxes and subsidies have the potential to play a crucial role in addressing this issue in this paper a provincial level dataset is used to estimate the price and income elasticities of aggregate coal demand by rural households we find that coal is a non giffen inferior good for the rural household sector this means that future income growth may help to induce switching from coal demand is becoming more price elastic as rural incomes grow we also find that rural residential coal demand is more price and income responsive in the south than the north perhaps because of fewer substitution options in the north our results provide benchmarks and parameters for policy simulation research

can market oriented economic reforms contribute to energy efficiency improvement evidence from china since china accelerated its market oriented economic reforms at the end of 1992 its energy intensity has declined 3 6 annually over 1993 2005 however its energy intensity declined 4 2 annually during its first reform period 1979 1992 therefore can we conclude that the accelerated marketization since the end of 1992 has made no contribution to its energy efficiency improvement in order to answer this challenging question we examine the changes of energy own price elasticity as well as the elasticities of substitution between energy and non energy capital and labor in china during the periods of 1979 1992 and 1993 2003 generally in transition or developing economies holding the technology and output level fixed if the energy own price elasticity algebraic value declines or the substitution elasticity between factors rises they will contribute to energy efficiency improvement our empirical study finds that 1 during 1979 1992 the energy own price elasticity is positive 0 285 and capital energy labor energy are both morishima complementary which indicates a distorted energy price and inefficient allocation and 2 during 1993 2003 the own price elasticity for energy is negative 1 236 and capital energy and labor energy are both morishima substitute all factor demands become more elastic and all elasticities of substitution increase the implication is that the accelerated marketization contributes substantially to energy efficiency improvement since 1993 c 2006 elsevier ltd all rights reserved

roscas as financial agreements to cope with self control problems abstract we consider a model in which people with limited self control can sign binding financial agreements among themselves thereby forming coalitions we show that these financial agreements may help them to alleviate their self control problems we then demonstrate that there exists a stable structure of coalitions in which people form rotating savings and credit associations roscas we therefore provide a behavioral rationale for one of the most prevalent and puzzling financial institutions in developing countries finally we derive and discuss some empirical predictions

micro finance competition motivated micro lenders double dipping and default abstract we develop a tractable model of competition among socially motivated mfis so that the objective functions of the mfis put some weight on their own clients utility we find that the equilibrium involves double dipping i e borrowers taking multiple loans from different mfis whenever the mfis are relatively profit oriented further double dipping necessarily leads to default and inefficiency and moreover borrowers who face relatively higher transactions costs optimally decide to double dip interestingly an increase in mfi competition can increase the extent of double dipping and default further the interest rates may go either way with the interest rate likely to increase with more competition if the mfis are very socially motivated

household fuel use in developing countries review of theory and evidence because of recent concerns about the negative externalities of traditional fuel use on the environment and health the issue of the household fuel transition in developing countries from dirty fuels towards clean fuels has received growing research attention this paper provides an up to date survey of the economic literature on household fuel use in these countries first we present the conceptual and theoretical frameworks then we discuss the empirical results that show how a wide range of factors drive the household fuel transition finally we suggest priorities for policy initiatives and highlight areas of future research

a dual self model of impulse control we propose that a simple dual self model gives a unified explanation for several empirical regularities including the apparent time inconsistency that has motivated models of quasi hyperbolic discounting and rabin s paradox of risk aversion in the large and small the model also implies that self control costs imply excess delay as in the o donoghue and rabin models of quasi hyperbolic utility and it explains experimental evidence that increased cognitive load makes temptations harder to resist the base version of our model is consistent with the gul pesendorfer axioms but we argue that these axioms must be relaxed to account for the effect of cognitive load

measuring self control problems we develop a survey instrument to measure self control problems in a sample of highly educated adults this measure relates in the manner that theory predicts to liquid wealth accumulation and personality measures yet while self control problems are typically seen as resulting in overconsumption and low wealth we identify a significant group who underconsume and thereby accumulate high levels of wealth in addition self control problems are smaller in scale for older than for younger respondents those who put money aside in retirement accounts may be delaying access to a point at which self control problems are no longer important jel d12 d14

how can african agriculture adapt to climate change a counterfactual analysis from ethiopia we analyze the impact of different adaptation strategies on crop net revenues in the nile basin of ethiopia we estimate a multinomial endogenous switching regression model of climate change adaptation and crop net revenues and implement a counterfactual analysis households data are combined with spatial climate data we find that adaptation to climate change based upon a portfolio of strategies significantly increases farm net revenues changing crop varieties has a positive and significant impact on net revenues when coupled with water conservation strategies or soil conservation strategies but not when implemented in isolation jel q54 q56

review of key international demand elasticities for major industrializing economies abstract this paper conducts a selective review of various estimates for energy demand responses focused specially upon lower income industrializing economies rather than richer mature nations it emphasizes recent trends from empirical studies that have been published after 2000 emphasis is placed on the five major emerging or transitional economies in brazil china india mexico and russia although other important nations like chile and south korea are also discussed when studies are available the review focuses attention on the long run responses to changes in prices and income after capital stock turnover has been completed the terminology often refers to elasticities or the percentage change in energy use divided by the percentage change in price or income holding constant all other factors that could influence energy use decisions estimates cover petroleum products natural gas and electricity although the available studies often ignore coal they also include the economy wide impacts real gdp to price changes most studies have focused upon household and transportation use of liquid fuels many fewer studies have investigated fuels used by industry or commerce or for electric generation based upon the available estimates price and income elasticities for liquid fuels are generally less than one unity for many countries and sectors except for the long run income effect for transportation purposes which can range widely by country between 0 24 and 1 75 while averaging 0 94 for all countries

determinants of household energy consumption in india improving access to affordable modern energy is critical to improving living standards in the developing world rural households in india in particular are almost entirely reliant on traditional biomass for their basic cooking energy needs this has adverse effects on their health and productivity and also causes environmental degradation this study presents a new generic modelling approach with a focus on cooking fuel choices and explores response strategies for energy poverty eradication in india the modelling approach analyzes the determinants of fuel consumption choices for heterogeneous household groups incorporating the effect of income distributions and traditionally more intangible factors such as preferences and private discount rates the methodology is used to develop alternate future scenarios that explore how different policy mechanisms such as fuel subsidies and micro financing can enhance the diffusion of modern more efficient energy sources in india

behavioral foundations of microcredit experimental and survey evidence from rural india microcredit is an innovative financial tool designed to reduce poverty and fix credit market imperfections we use experimental measures of time discounting and risk aversion for villagers in south india to highlight behavioral features of microcredit conditional on borrowing from any source women with present biased preferences are more likely than others to borrow through microcredit institutions microcredit contracts require loan repayments in regular fixed installments and they harness peer pressure to encourage discipline these innovations mirror mechanisms highlighted in behavioral approaches to saving suggesting that microcredit s popularity stems partly from modes of encouragement and self discipline absent in typical lending mechanisms

evaluating seasonal food storage and credit programs in east indonesia abstract predictable annual lean seasons occur in many rural areas including west timor in indonesia imperfections in savings and credit markets make it difficult for staple farmers to convert harvest season output into lean season consumption we conduct a randomized evaluation of a seasonal food storage program and a food credit program by providing improved ways to transfer assets across seasons each program functions as a subsidy on lean season consumption we find that neither program had effects on staple food consumption the storage program increased non food consumption the credit program increased reported income and reduced seasonal gaps in consumption our results are consistent with positive income effects through the expansion of budget sets but suggest that the average household could be close to staple food satiation

consumption savings decisions with quasi geometric discounting we study the consumption savings problem of an infinitely lived rational consumer who has time inconsistent preferences in the form of quasi geometric discounting the consumer operates a weakly concave production function and must simply divide current resources into current consumption and savings there is no uncertainty a solution to the consumer s problem is a subgame perfect equilibrium of a dynamic game between the consumer s successive selves we show that this game has a continuum of equilibria in stationary markov strategies not only is the stationary point of the consumer s asset holdings indeterminate but each stationary point has a continuum of dynamic paths converging to it the savings policy rules underlying these dynamic paths are step functions

phasing out coal and phasing in renewables good or bad news for arctic gas producers abstract this paper examines to what extent downscaling of global coal based electricity generation encourages gas demand and affects regional activity in gas production with emphasis on the arctic regions in our reference scenario up to 2050 we take into consideration that renewables is set to increase its contribution to global electricity production over time while coal will contribute less we find that a policy scenario with further phasing out of coal and phasing in of renewables in line with the 2 c scenario for the power sector up to 2050 will lead to reduced arctic gas production compared to the reference scenario although total worldwide electricity production doubles over the same period however even in a situation with less resources in the arctic future investments in new reserves in the region are still profitable in our 2 c policy scenario as total arctic gas production is marginally higher in 2050 than today

energy consumption in rural china a household model for three villages in jiangxi province abstract in china fuelwood and coal are the most important energy sources for rural households in poor areas along with population and economic growth excessive fuelwood collection is a major cause of deforestation burning coal contributes to environmental problems such as air pollution acid rain and greenhouse gas emissions the purpose of this article is to analyze factors determining choice of energy source and labor input into fuelwood collection in poor forest rich regions and to provide policy recommendations on ways to affect these choices to this end a nonseparable household model reflecting choices in labor allocation and energy demand of rural households is estimated from available data for three villages in a poor forest rich region in jiangxi province southeast china innovative aspects of this article are the analyses of factors driving household substitution between forest and non forest fuels and of dissimilarities in household responses under different market access conditions

george bush versus al gore irreversibilities in greenhouse gas accumulation and emission control investment abstract this paper investigates the fundamental problem of mitigating the impacts of climate change in an environment of uncertainty and learning in particular the paper uses a stochastic version of nordhaus s dice model to show that the irreversibility of investment capital has a stronger effect than irreversibilities in climate change other than catastrophic effects the implications are that if abatement decisions are irreversible there should be less emission control today than would be optimal without taking learning into account and that policy makers should pursue control policies that are costlessly reversible a variant on the no regrets strategy

the impact of group based credit programs on poor households in bangladesh does the gender of participants matter this paper estimates the impact of participation by gender in the grameen bank and two other group based micro credit programs in bangladesh on labor supply schooling household expenditure and assets the empirical method uses a quasi experimental survey design to correct for the bias from unobserved individual and village level heterogeneity we find that program credit has a larger effect on the behavior of poor households in bangladesh when women are the program participants for example annual household consumption expenditure increases 18 taka for every 100 additional taka borrowed by women from these credit programs compared with 11 taka for men

commitment savings in informal banking markets abstract i study the provision of commitment savings by informal banks to sophisticated hyperbolic discounters since a consumer is subject to temptation in the period that he signs a contract banks might exploit his desire for instant gratification even as they help him to commit for the future without banking savings decisions and welfare are not monotonic in the degree of time inconsistency consequently commitment savings will lower welfare for moderately time inconsistent agents if loan contracts are enforceable pure commitment savings will disappear this will further lower welfare if the lender is a profit maximizing bank but raise welfare if the lender is a welfare maximizing ngo finally i consider the coexistence of a bank and ngo there will be zero takeup of ngo provided commitment savings if there is competition from a moneylender but the ngo s offer will raise the agent s reservation utility thus reducing the surplus that can be extracted by the moneylender

tying odysseus to the mast evidence from a commitment savings product in the philippines we designed a commitment savings product for a philippine bank and implemented it using a randomized control methodology the savings product was intended for individuals who want to commit now to restrict access to their savings and who were sophisticated enough to engage in such a mechanism we conducted a baseline survey on 1777 existing or former clients of a bank one month later we offered the commitment product to a randomly chosen subset of 710 clients 202 28 4 percent accepted the offer and opened the account in the baseline survey we asked hypothetical time discounting questions women who exhibited a lower discount rate for future relative to current trade offs and hence potentially have a preference for commitment were indeed significantly more likely to open the commitment savings account after twelve months average savings balances increased by 81 percentage points for those clients assigned to the treatment group relative to those assigned to the control group we conclude that the savings response represents a lasting change in savings and not merely a short term response to a new product

bioenergy consumption in rural china evidence from a survey in three provinces abstract biomass in the form of crop residues and firewood is a major energy source for rural households in china a survey conducted in the provinces of shanxi zhejiang and guizhou shows that 37 percent of rural households use bioenergy for heating and cooking and that bioenergy accounts for 18 percent of their total energy consumption most of the biomass used for energy is burned in traditional stoves contributing to indoor air pollution in rural homes crop residues also are commonly burned in the fields contributing to the high level of outdoor air pollution in china our econometric analysis of the key determinants of bioenergy use shows that bioenergy consumption falls modestly with income growth increased time required for biomass collection and less farmland hence open burning of some biomass is an optimal choice and is likely to become more of a problem without policy intervention these findings suggest that a more sustainable use of biomass requires policies that promote cleaner more efficient bioenergy combustion technologies and increase the economic value of biomass such that local households can benefit from biomass collection

exploiting naivete about self control in the credit market we develop a model of the credit market where competitive lenders oer long term contracts specifying a non linear schedule of possible repayment schedules to borrowers who may dier both in their taste for immediate gratication and their prior beliefs about that taste the equilibrium contract to a borrower with given beliefs is discontinuous it features an advantageous option involving fast repayment and a penalty for deviating and repaying later these predictions seem to resemble some salient features of many credit card and mortgage contracts for fully sophisticated borrowers the discontinuity acts as a commitment device and yields fast repayment but all other borrowers even those with an arbitrarily small amount of naivete end up delaying repayment despite the penalty and receive little benet from commitment furthermore because they believe they will repay early they underestimate the cost of credit and hence borrow too much non sophisticated borrowers cross subsidize sophisticated borrowers while sophisticated borrowers discipline rms by preventing very exploitative contracts we identify natural conditions under which the above results obtain even if

a behavioral economics view of poverty standard theorizing about poverty falls into two camps social scientists regard the behaviors of the economically disadvantaged either as calculated adaptations to prevailing circumstances or as emanating from a unique culture of poverty rife with deviant values the first camp presumes that people are highly rational that they hold coherent and justified beliefs and pursue their goals effectively without mistakes and with no need for help the second camp attributes to the poor a variety of psychological and attitudinal short fallings that render their views often misguided and their choices fallible leaving them in need of paternalistic guidance we propose a third view the behavioral patterns of the poor we argue may be neither perfectly calculating nor especially deviant rather the poor may exhibit the same basic weaknesses and biases as do people from other walks of life except that in poverty with its narrow margins for error the same behaviors often manifest themselves in more pronounced ways and can lead to worse outcomes in what follows we illustrate the kinds of insights that might be gained from a behaviorally more realistic analysis of the economic conditions of the poor and we propose that alternative policies for alleviating poverty be considered

quasi hyperbolic preferences and retirement a comment abstract diamond and koszegi diamond p and koszegi b 2003 quasi hyperbolic preferences and retirement journal of public economics 87 1839 1972 have argued that quasi hyperbolic discounting can cause dynamic inconsistency in planning when to retire as well as in consumption plans this comment shows that in a simple model with such preferences retirement plans are never time inconsistent as these same preferences keep savings too low for individuals to ever be able to afford unplanned early retirement although only a simple example is presented here to demonstrate the point this insight suggests the application of ordiamond03 s framework should be reconsidered the model presented needs to be extended to find robust general conclusions

contracting with diversely naive agents in standard contract theoretic models the underlying assumption is that agent types differ in their preference or cost parameters and the principal s objective is to design contracts in order to screen this type we study a contract theoretic model in which the heterogeneity among agent types is of a cognitive nature in our model the agent has dynamically inconsistent preferences agent types differ only in their degree of sophistication that is their ability to forecast the change in their future tastes we fully characterize the menu of contracts which the principal offers in order to screen the agent s sophistication the menu does not exclude any type it provides a perfect commitment device for relatively sophisticated types and exploitative contracts which involve speculation with relatively naive types more naive types are more heavily exploited and generate a greater profit for the principal our results allow us to interpret real life contractual arrangements in a variety of industries

the impacts of energy prices on energy intensity evidence from china in this paper we present a review of the deregulation of energy prices in china between 1985 and 2004 and assess the impacts of changes in energy prices on aggregate energy intensity and coal oil electricity intensity we used time series data to provide estimates of energy price elasticities empirical results showed that 1 the own price elasticities of coal oil and aggregate energy were negative in periods both before and after 1995 implying that higher relative prices of different energy types lead to the decrease in coal oil and aggregate energy intensities however the positive own price elasticity of electricity after 1995 probably indicates that the price effect was weaker than other factors such as income effect and population effect 2 the impacts of energy prices were asymmetric over time 3 sectoral adjustment also drove the decrease in aggregate energy intensity although raising energy prices to boost efficiency of energy use seems to be an effective policy tool other policy implications concerned with energy prices such as energy supply security and fuel poverty must also be considered

price and income elasticities of residential energy demand in germany we apply a quadratic expenditure system to estimate price and expenditure elasticities of residential energy demand electricity and heating in germany using official expenditure data from 1993 to 2008 we estimate an expenditure elasticity for electricity of 0 3988 and of 0 4055 for space heating the own price elasticity for electricity is 0 4310 and 0 5008 in the case of space heating disaggregation of households by expenditure and demographic composition reveals that the behavioural response to energy price changes is weaker stronger for low income top income households there are considerable economies of scale in residential energy use but scale effects are not well approximated by the new oedc equivalence scale real increases in energy prices show a regressive pattern of incidence implying that the welfare consequences of direct energy taxation are larger for low income households the application of zero elasticities in assessments of welfare consequences of energy taxation strongly underestimates potential welfare effects the increase in inequality is 22 smaller when compared to the application of rich and disaggregated behavioural response patterns as estimated in this paper