an economic theory of self control the concept of self control is incorporated in a theory of individual intertemporal choice by modeling the individual as an organization the individual at a point in time is assumed to be both a farsighted planner and a myopic doer the resulting conflict is seen to be fundamentally similar to the agency conflict between the owners and managers of a firm both individuals and firms use the same techniques to mitigate the problems which the conflicts create this paper stresses the implications of this agency model and discusses as applications the effect of pensions on saving saving and the timing of income flows and individual discount rates

how general are time preferences eliciting good specific discount rates abstract this paper tests the commonly used assumption that people apply a single discount rate to the utility from different sources of consumption using survey data from uganda with both hypothetical and incentivized choices over different goods we elicit time preferences from about 2400 subjects we reject the null of equal discount rates across goods the average person in our sample is more impatient about sugar meat and starchy plantains than about money and a list of other goods we review the assumptions to recover discount rates from experimental choices for the case of good specific discounting consistently with the theoretical framework we find convergence in discount rates across goods for two groups expected to engage in or think about arbitraging the rewards traders and individuals with large quantities of the good at home as an application we evaluate empirically the conditions under which good specific discounting could predict a low asset poverty trap

discount rates and credit markets theory and evidence from rural india three models of credit markets 1 the permanent income model 2 upward sloping credit supply to individual borrowers and 3 constrained credit due to imperfect enforcement are tested using credit market data and an experimental study of individuals discount rates in south india the permanent income model is rejected by both the discount rate and the credit market data the discount rate data are consistent with either of the other two models while the credit market data are consistent with a combination of these two models other explanations are found to be insufficient to explain the results of this study

working over time dynamic inconsistency in real effort tasks experimental tests of dynamically inconsistent time preferences have largely relied on choices over time dated monetary rewards several recent studies have failed to nd the standard patterns of present bias however such monetary studies contain oftendiscussed confounds in this paper we sidestep these confounds and investigate choices over consumption real eort in a longitudinal experiment we pair this eort study with a companion monetary discounting study we conrm very limited time inconsistency in monetary choices however subjects show considerably more present bias in eort furthermore present bias in the allocation of work has predictive power for demand of a meaningfully binding commitment device therefore our ndings validate a key implication of models of dynamic inconsistency with corresponding policy implications

sustainability limited substitutability and non constant social discount rates abstract the paper shows how limited substitutability in consumption between different classes of goods affects the magnitude and time development of social discount rates it decomposes the discount rates into an absolute growth and a relative growth or substitutability effect the paper relates between good and intertemporal substitutability to the notions of weak and strong sustainability it analyzes under which circumstances low as opposed to high between good substitutability increases the weights given to long run environmental services

axiomatization and measurement of quasi hyperbolic discounting this article provides an axiomatic characterization of quasi hyperbolic discounting and a more general class of semi hyperbolic preferences we impose consistency restrictions directly on the intertemporal trade offs by relying on what we call annuity compensations our axiomatization leads naturally to an experimental design that disentangles discounting from the elasticity of intertemporal substitution in a pilot experiment we use the partial identification approach to estimate bounds for the distributions of discount factors in the subject pool consistent with previous studies we find evidence for both present and future bias jel codes c10 c99 d03 d90

inferring discount rates from time preference experiments abstract we observe that identification of the discount rate from experimental data requires an assumption about the consumption period the length of time over which a payment will be turned into utility providing consumption we show that the optimal consumption period is substantially longer than assumed in previous studies when the consumption period is allowed to take on more reasonable values the discount rates implied by experimental choices are unreasonably large and relatively insensitive to assumptions about utility curvature

the stability of measured time preferences abstract we use a panel dataset to test the stability of measured discount rates over time in response to changes in both macroeconomic events and household level labor market outcomes while discount rate measures are constructed to capture a rate of time preference our evidence is inconsistent with such an interpretation our results more closely align with the interpretation that standard methods to elicit discount rates reveal the market interest rate faced by an individual rather than their pure rate of time preference it follows directly from such an interpretation that factors which influence the interest rate at which a household can borrow and lend such as the inflation rate and household income ought to be correlated with the elicited discount rate a prediction supported by our data

discounting behaviour and the magnitude effect evidence from a field experiment in denmark we evaluate the claim that individuals exhibit a magnitude effect in their discounting behaviour where higher discount rates are inferred from choices made with lower principals all else being equal if the magnitude effect is quantitatively significant it is not appropriate to use one discount rate that is independent of the scale of the project for cost benefit analysis and capital budgeting using data from a field experiment in denmark we find statistically significant evidence of a magnitude effect that is much smaller than is claimed this evidence surfaces only if one controls for unobserved individual heterogeneity in the population

the economics of roscas and intrahousehold resource allocation this paper investigates individual motives to participate in rotating savings and credit associations roscas detailed evidence from roscas in a kenyan slum nairobi suggests that most roscas are predominantly composed of women particularly those living in a couple and earning an independent income to explain this phenomenon we propose an argument based on conflictual interactions within the household participation in a rosca is a strategy a wife employs to protect her savings against claims by her husband for immediate consumption the empirical implications of the model are then tested using the data collected in kenya

why do sellers usually prefer auctions we compare the most common methods for selling a company or other asset when participation is costly a simple simultaneous auction and a sequential process in which potential buyers decide in turn whether to enter the bidding the sequential process is always more efficient but preemptive bids transfer surplus from the seller to buyers because the auction is more conducive to entry precisely because of its inefficiency it usually generates higher expected revenue we also discuss the effects of lock ups matching rights break up fees as in takeover battles entry subsidies etc

how general are risk preferences choices under uncertainty in different domains we analyze the extent to which individuals choices over five employer provided insurance coverage decisions and one 401 k investment decision exhibit systematic patterns as would be implied by a general utility component of risk preferences we provide evidence consistent with an important domain general component that operates across all insurance choices we find a considerably weaker relationship between one s insurance decisions and 401 k asset allocation although this relationship appears larger for more financially sophisticated individuals estimates from a stylized coverage choice model suggest that up to thirty percent of our sample makes choices that may be consistent across all six domains

the economic lives of the poor in what turned out to be a rhetorical master move the 1990 world development report from the world bank defined the extremely poor people of the world as those who are currently living on no more than 1 per day per person measured at the 1985 purchasing power parity ppp exchange rate in 1993 the poverty line was updated to 1 08 per person per day at the 1993 ppp exchange rate which is the line we use in this paper poverty lines have always existed indeed 1 per day was chosen in part because of its proximity to the poverty lines used by many poor countries 1 however the 1 a day poverty line has come to dominate the conversations about poverty to a remarkable extent

present bias quasi hyperbolic discounting and fixed costs in this paper we elicit preferences for money time pairs via experimental techniques we estimate a general specification of discounting that nests exponential and hyperbolic discounting as well as various forms of present bias including quasi hyperbolic discounting our experimental data do not appear peculiar in any dimension in particular we find clear evidence for present bias as most of the previous literature however no evidence for quasi hyperbolic discounting is found and the data strongly favor instead a specification with a small present bias in the form of a fixed cost of the order of 4 on average across subjects with such a fixed cost the curvature of discounting is imprecisely estimated and exponential discounting is hardly rejected in this specification the present bias tends to vanish for economically relevant monetary rewards

are risk aversion and impatience related to cognitive ability is the way that people make risky choices or tradeoffs over time related to cognitive ability this paper investigates whether there is a link between cognitive ability risk aversion and impatience using a representative sample of the population and incentive compatible measures we conduct choice experiments measuring risk aversion and impatience over an annual time horizon for a randomly drawn sample of roughly 1 000 german adults subjects also take part in two different tests of cognitive ability which correspond to sub modules of one of the most widely used iq tests interviews are conducted in subjects own homes we find that lower cognitive ability is associated with greater risk aversion and more pronounced impatience these relationships are significant and robust to controlling for personal characteristics educational attainment income and measures of credit constraints we perform a series of additional robustness checks which help rule out other possible confounds

does africa need a rotten kin theorem experimental evidence from village economies this paper measures the economic impact of social pressure to share income with kin and neighbors in rural kenyan villages the authors conduct a lab experiment in which they randomly vary the observability of investment returns the goal is to test whether subjects reduce their income in order to keep it hidden the analysis finds that women adopt an investment strategy that conceals the size of their initial endowment in the experiment although that strategy reduces their expected earnings this effect is largest among women with relatives attending the experiment parameter estimates suggest that women behave as though they expect to be pressured to share four percent of their observable income with others and substantially more when close kin can observe income directly although this paper provides experimental evidence from a single african country observational studies suggest that similar pressure from kin may be prevalent in many rural areas throughout sub saharan africa

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

participation and exclusion in auctions we provide extensions of the bulow and klemperer 1996 result when the seller has value for the object above the minimum value of the buyers the result may fail we show that the seller does better with more participation and some exclusion than the optimal exclusion of buyers of low value types some amount of exclusion which is independent of the number of buyers in the form of the minimum bid is needed to make participation the dominant method for improving the seller payoff from the auctions there exists n0 which depends on the seller valuation such that more participation with no exclusion is dominant if and only if the number of participants exceeds n0

poverty and economic decision making evidence from changes in financial resources at payday we study the effect of financial resources on decision making low income u s households are randomly assigned to receive an online survey before or after payday the survey collects measures of cognitive function and administers risk and intertemporal choice tasks the study design generates variation in cash checking and savings balances and expenditures before payday participants behave as if they are more present biased when making intertemporal choices about monetary rewards but not when making intertemporal choices about non monetary real effort tasks nor do we find before after differences in risk taking the quality of decision making the performance in cognitive function tasks or in heuristic judgments

time discounting for primary and monetary rewards this paper reports a positive and statistically significant relation between short term discount rates elicited with a monetary and a primary reward chocolate the relation is most evident among people who like chocolate and are hungry this finding suggests that high short term discount rates are related to an underling individual trait consistent with models of presentbiased preferences

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

discounting behavior a reconsideration we re evaluate the theory experimental design and econometrics behind claims that individuals exhibit non constant discounting behavior theory points to the importance of controlling for the non linearity of the utility function of individuals since the discount rate is defined over time dated utility flows and not flows of money it also points to a menagerie of functional forms to characterize different types of non constant discounting behavior the implied experimental design calls for individuals to undertake several tasks to allow us to identify these models and to several treatments such as multiple horizons and the effect of allowing for a front end delay on earlier payments the implied econometrics calls for structural estimation of the theoretical models allowing for joint estimation of utility functions and discounting functions using data collected from a representative sample of 413 adult danes in 2009 we draw striking conclusions assuming an exponential discounting model we estimate discount rates to be 5 6 on average this is significantly lower than all previous estimates using controlled experiments we also find no evidence to support quasi hyperbolic discounting or fixed cost discounting and only modest evidence to support other specifications of non constant discounting furthermore the evidence for non constant discounting while statistically significant is not economically significant in terms of the size of the estimated discount rates we undertake extensive robustness checks on these findings including a detailed review of the previous comparable literature

temporal stability of time preferences abstract the preferences assumed to govern intertemporal trade offs are generally considered to be stable economic primitives though evidence on this stability is notably lacking we present evidence from a large field study conducted over two years with around 1 400 individuals using incentivized intertemporal choice experiments aggregate choice profiles and corresponding estimates of discount parameters are unchanged over the two years and individual correlations through time are high by existing standards however some individuals show signs of instability by linking experimental measures to administrative tax records we showthat identified instability is uncorrelated with both levels and changes in sociodemographic variables

risk attitudes and economic well being in latin america abstract a common conjecture in both the theoretical and policy literatures on development is that people remain poor because they are too impatient and risk averse to accumulate the resources needed to improve their well being the empirical literature however suggests that this conjecture is far from proven we sample more than 3000 participants drawn representatively from six latin american cities and find little correlation between baseline risk aversion and well being measured as an index of eight outcomes we do however find that measures of ambiguity aversion loss aversion and the willingness to take advantage of a risk pooling scheme all correlate with well being participants who are ambiguity averse loss averse and who react conservatively in the risk pooling condition all have significantly lower scores on our well being index these results are robust to the inclusion of a variety of important controls like human capital accumulation and access to credit

food and cash transfers evidence from colombia we study food engel curves among the poor population targeted by a conditional cash transfer programme in colombia after controlling for the endogeneity of total consumption and for the price variability across villages our estimates imply that an increase in consumption by 10 would lead to a decrease of 1 in the share of food however quasi experimental estimates of the impact of the programme show that the share of food increases this result is not inconsistent with the hypothesis that the programme could increase the bargaining power of women inducing a more than proportional increase in food consumption

spousal control and intra household decision making an experimental study in the philippines i elicit causal effects of spousal observability and communication on financial choices of married individuals in the philippines when choices are private men put money into their personal accounts when choices are observable men commit money to consumption for their own benefit when required to communicate men put money into their wives account these strong treatment effects on men but not women appear related more to control than to gender men whose wives control household savings respond more strongly to the treat ment and women whose husbands control savings exhibit the same response changes in information and communication interact with underlying control to produce mutable gender specific outcomes

demand estimation with expenditure measurement errors on the left and right hand side let x be total consumption expenditures measurement errors in consumer budget allocation models cause unusual problems because errors in the dependent variables consumption on individual goods contribute to errors in the regressor x empirically adequate budget share models like the aids translog and quadratic aids are linear or quadratic in log x it is shown that for these specifications two stage least squares fails to correct for the measurement error a simple technique for recovering consistent estimates from two stage least squares is provided along with an efficient generalized method of moments estimator the method is applied to u k fuel demand data copyright 1996 by mit press

hyperbolic discounting and the standard model eliciting discount functions abstract experiments on static intertemporal choice find evidence of particularly extreme impatience toward immediate rewards while this is often taken as support for hyperbolic discounting it could also arise because the most likely participants in experiments may be those with the most immediate need for money we conduct a calibration exercise and find that the extreme impatience observed in experiments can be accommodated by a standard exponential discounting model with no discounting and expectation of a small increase in the base consumption level the calibration uses existing estimates of curvature of utility

nudging farmers to use fertilizer theory and experimental evidence from kenya we model farmers as facing small fixed costs of purchasing fertil izer and assume some are stochastically present biased and not fully sophisticated about this bias such farmers may procrastinate post poning fertilizer purchases until later periods when they may be too impatient to purchase fertilizer consistent with the model many farmers in western kenya fail to take advantage of apparently profit able fertilizer investments but they do invest in response to small time limited discounts on the cost of acquiring fertilizer free deliv ery just after harvest calibration suggests that this policy can yield higher welfare than either laissez faire policies or heavy subsidies

judging experimental evidence on dynamic inconsistency abstract this article briefly summarizes and judges recent experimental developments exploring the predictions of dynamically inconsistent models an opinion is provided as to how the literature ma

narrow bracketing and dominated choices an experiment by tversky and kahneman 1981 illustrates that people s tendency to evaluate risky decisions separately can lead them to choose combinations of choices that are first order stochastically dominated by other available combinations we investigate the generality of this effect both theoretically and experimentally we show that for any decisionmaker who does not have constant absolute risk averse preferences and who evaluates her decisions one by one there exists a simple pair of independent binary decisions where the decisionmaker will make a dominated combination of choices we also characterize as a function of a person s preferences the amount of money that she can lose due to a single mistake of this kind the theory is accompanied by both a real stakes laboratory experiment and a large sample survey from the general u s population replicating tversky and kahneman s original experiment where decisionmakers with prototypical prospect theory preferences will choose a dominated combination we find that 28 of the participants do so in the survey we ask the respondents about several hypothetical large stakes choices and find higher proportions of dominated choice combinations a statistical model that estimates preferences from the survey results is best fit by assuming people have utility functions that are close to prospect theory value functions and that about 83 of people bracket narrowly none of these results varies strongly with the personal characteristics of participants we also demonstrate directly that dominated choices are driven by narrow bracketing when we eliminate the possibility of narrow bracketing by using a combined presentation of the decisions the dominated choices are eliminated in the laboratory experiment and are greatly reduced in the survey

bidding and renegotiation in procurement auctions abstract in this paper we study renegotiation in procurement auctions a procurer with private valuation announces a project which can be completed by many firms these firms submit bids which may be renegotiated upon later in the equilibrium we characterize the probability of renegotiation is decreasing in both the cost of renegotiation and the number of firms we conclude that the initial bids are more than cheap talk these prices serve simultaneously as bids to win the contract and signals of the firms costs finally we compare our model to other renegotiation models in the literature

the demand for food and calories we investigate nutrition and expenditure in rural maharashtra in india we estimate that the elasticity of calorie consumption with respect to total expenditure is 0 3 0 5 a range that is in accord with conventional wisdom the elasticity declines only slowly with levels of living and is far from the value of zero suggested by a recent revisionist literature in these indian data the calories necessary for a day s activity cost less than 5 percent of the daily wage which makes it implausible that income is constrained by nutrition rather than the other way around

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

hedging size risk theory and application to the us gas market abstract many corporate commitments exhibit a combined financial exposure to both market prices and idiosyncratic size components e g volume load or business turnover we design a customized contract to optimally mitigate the risk of joint fluctuations in price and size terms the hedge is sought out among contingent claims written on price and any quoted index that is statistically dependent on commitment size closed form solutions are derived for the optimal custom hedge pay off and for the asset holdings of two market strategies one based on price linked forwards the other based on price linked and index linked forwards analytical hedges are obtained using a stylized lognormal market model detailed comparative statics provide a thorough analysis of optimal hedging pay off functions performance assessment is conducted in the context of the us gas market and a prototypical urban region results suggest that hedging through suitable custom claims written on price and an additional index significantly outperforms standard price based as well as mixed price index forward hedging alternatives our optimal custom hedge could be adopted as a benchmark for the relative assessment of any risk management solution

estimating time preferences from convex budgets experimentally elicited discount rates are frequently higher than what seems reasonable for economic decision making such high rates are often attributed to present biased discounting a well known bias of standard measurements is the assumption of linear consumption utility attempting to correct this bias using measures of risk aversion to identify concavity researchers find reasonable discounting but at the cost of exceptionally high utility function curvature we present a new methodology for identifying time preferences both discounting and curvature from simple allocation decisions we find reasonable levels of both discounting and curvature and surprisingly dynamically consistent time preferences jel c91 d12 d81 understanding and estimating time preferences is obviously of great importance to economists marketers and policy makers consumers decide how much to invest in savings education real estate and life insurance how much to diet exercise and smoke whether to marry when to have children and what to leave in their wills while there has been substantial research estimating time preferences using aggregate consumption data 1 the bulk of the effort has occurred in laboratory environments 2 among the many laboratory techniques employed recent studies have favored multiple price lists mpl with monetary payments 3 with mpls individuals are asked multiple times to choose between smaller payment amounts closer to the present and larger amounts further into the future the interest rate increases monotonically in a price list such that the point where an individual switches from preferring sooner payments to later payments carries interval

auctions versus negotiations which is the more profitable way to sell a company an auction with no reserve price or an optimally structured negotiation with one less bidder we show under reasonable assumptions that the auction is always preferable when bidders signals are independent for affiliated signals the result holds under certain restrictions on the seller s choice of negotiating mechanism the result suggests that the value of negotiating skill is small relative to the value of additional competition the paper also shows how the analogies between monopoly theory and auction theory can help derive new results in auction theory jel d44 g34 there are close analogies between standard price theory and the theory of auctions in an absolute english auction in which the price rises continuously until only one bidder remains and the seller is required to accept the final bid the sale price equals the lowest competitive price at which supply equals demand in the theory of optimal auctions the seller is treated as a monopolist who can choose any

time consistency stationarity and time invariance a sequence of experiments documents static and dynamic preference reversals between sooner smaller and later larger rewards when the sooner reward could be immediate the theoretically motivated design permits separate identification of time consistent stationary a ndtime invariant choices at least half of the subjects are time consistent but only three quarters of them exhibit stationary choices about half of subjects with time inconsistent choices have stationary preferences these results chal lenge the view that present bias preferences are the main source of time inconsistent choices the past twenty years have seen a surge of interest in time inconsistent preferences mostly this has been motivated by psychological experiments and introspection that have suggested the existence of present bias a decision maker prefers smaller immediate reward to a larger delayed reward but when she is asked about her preferences between these two alternatives when both are equally shifted into the future her preferences are reversed although there is no inconsistency per se in her answers this behavior has been taken to suggest that when the decision maker will be asked to update her choices in the future she will generally deviate from her ex ante plans our goal in the present study is to perform a dynamic preference reversal experiment as such one is required to extend the standard framework of pref erences over temporal payments to a dated collection of such preferences this extension allows us to formally define three distinct properties stationarity im plies that ranking of temporal payments depends only on the time distance and payment distance between the alternatives time invariance assumes that the decision maker evaluates each temporal payment relative to the evaluation pe

quadratic engel curves and consumer demand this paper presents a model of consumer demand that is consistent with the observed expenditure patterns of individual consumers in a long time series of expenditure surveys and is also able to provide a detailed welfare analysis of shifts in relative prices a nonparametric analysis of consumer expenditure patterns suggests that engel curves require quadratic terms in the logarithm of expenditure while popular models of demand such as the translog or the almost ideal demand systems do allow flexible price responses within a theoretically coherent structure they have expenditure share engel curves that are linear in the logarithm of total expenditure we derive the complete class of integrable quadratic logarithmic expenditure share systems a specification from this class is estimated on a large pooled data set of u k households models that fail to account for engel curvature are found ro generate important distortions in the patterns of welfare losses associated with a tax increase