Group concept mapping methodology: toward an epistemology of group conceptualization,complexity, and emergence

Quality & Quantity - Group concept mapping is a participatory mixed-methods approach to social and behavioral research that integrates qualitative group processes with multivariate statistical...     

The economic impact of bean disease resistance research in Honduras

This paper presents evidence of recent adoption rates of disease resistant bean varieties (RVs), the farm‐level benefits of RV adoption, and the ex post rate of return to disease resistant bean research in Honduras. Results from a farm‐level survey in 2001 in the two principal bean‐producing regions of the country show that 41–46% of bean farmers (depending upon the season) have adopted an RV, and that adoption is neutral with respect to farm‐size and market orientation. An expected utility framework was used to estimate the farm‐level benefits of RV adoption, using a combination of experimental trial and farm‐level survey data. Adopters gain the equivalent of 7–16% (depending on the variety) in bean income from the yield loss averted through RV use. The ex post rate of return to disease resistant bean research in Honduras from 1984 to 2010 is 41.2%.     

Repetition, reputation, and raiding

I develop a multitarget takeover model with bid revisions, inwhich bidders desire a reputation for having low valuations.Such a reputation increases the likelihood that future targetswill accept low premium bids. Bidders develop reputation byusing low take-it-or-leave-it offers. Consequently, tender premiums,bid revision rates, and success rates are lower for continuingbidders than for those considering only a single target. Successrates vary within a series, and reputation building is morelikely with highly correlated target valuations. I provide anexploratory empirical analysis consistent with lower premiumsfrom continuing bidders and discuss some resulting implicationisregarding 'raiders', conglomerates, and resistance strategies.     

Renegotiation and the impossibility of optimal investment

In a model with asymmetric information and external equity financingit is impossible to achieve socially optimal investment becauseof renegotiation possibilities. The contractual solution suggestedby Dybvig and Zender (1991) is not dynamically consistent -the manager's contract would be renegotiated, resulting in inefficientinvestment. Moreover, no other compensation contract that wouldinduce the manager to invest efficiently survives renegotiation.Contracts that pay the manager based on the stock price, whileproducing suboptimal investment as in Myers and Majluf (1984),are robust to renegotiation.     

Boom and bust patterns in the adoption of financial innovations

We develop a dynamic model of the adoption of financial innovations.Each period, firms decide whether or not to adopt an innovationof uncertain value, and the profitability of each period's adoptionsreveals information about the innovations's value. We show thatcharacteristics of financial innovation waves cited by criticsas evidence of irrational excess are, in fact, consistent withfully rational behavior. We also show that social welfare isenhanced when more firms adopt innovations of questionable valueand that financial intermediaries have an incentive to encouragesuch adoption.     

Stock price distributions with stochastic volatility: an analytic approach

We study the stock price distributions that arise when pricesfollow a diffusion process with a stochastically varying volatilityparameters. We use analytic techniques to derive an explicitclosed-form solution for the case when volatility is drivenby an arithmetic Ornstein-Uhlenbeck (or AR1) process. We thenapply our results to two related problems in the finance literature:(i) options pricing in a world of stochastic volatility, and(ii) the relationship between stochastic volatility and thenature of 'fat tails' in stock price distributions.     

Recovering risk aversion from option prices and realized returns

A relationship exists between aggregate risk-neutral and subjectiveprobability distributions and risk aversion functions. We empiricallyderive risk aversion functions implied by options prices andrealized returns on the S&P500 index simultaneously. Theserisk aversion functions dramatically change shapes around the1987 crash: Precrash, they are positive and decreasing in wealthand largely consistent with standard assumptions made in economictheory. Postcrash, they are partially negative and partiallyincreasing and irreconcilable with those assumptions. Mispricingin the option market is the most likely cause. Simulated tradingstrategies exploiting this mispricing show excess returns, evenafter accounting for the possibility of further crashes, transactioncosts, and hedges against the downside risk.     

The economic costs and benefits of a participatory project to conserve maize landraces on farms in Oaxaca,Mexico⋆

Conventional methods were used to assess the benefits and costs of an unconventional project whose purpose was to test whether participatory crop improvement can encourage Mexican farmers to continue growing maize landraces by enhancing their current use value. Findings suggest that farmers as a group earned a high benefit‐cost ratio from participating, though from the perspective of the private investor the returns were low. The project also generated social benefits, but these would be difficult (and costly) to measure. There was a gender bias in both participation and benefits distributions, though there is some evidence of a welfare transfer to maize deficit households. Application of other valuation approaches will be necessary in order to assess both the private and social benefits of similar projects.