Investigating the performance of different estimation techniques for crop yield data analysis in crop insurance applications

We investigate the performance of the ordinary least squares (OLS)‐, M‐, MM‐, and the Theil–Sen (TS)‐estimator for crop yield data analysis in crop insurance applications using Monte Carlo simulations. More specifically, the performance is assessed with respect to trend estimation, prediction of future yield levels, and the estimation of expected indemnity payments. In agreement with earlier findings, other estimators are found to be superior to OLS in simple regression problems if yield distributions are outlier contaminated and heteroscedastic. While this conclusion is also valid for subsequent applications such as yield prediction and the estimation of expected indemnity payments, the difference between the considered estimators becomes less distinct. For these applications, we find particularly the M‐estimator to be a good compromise between high‐breakdown (very robust) estimators and the very efficient OLS‐estimator. Because no regression technique dominates all others in all applications and scenarios for error term distributions, our results underline that the choice of the estimation technique should be dependent on the purpose of the crop yield data analysis. However, alternative estimators such as M‐, MM‐, and TS‐estimator can reduce (and bound) the risk of unreliable or inefficient crop yield data analysis in crop insurance applications.     

Climate change adaptation actions by fish farmers: evidence from the Niger Delta Region of Nigeria

This paper examined climate change adaptation strategies in fish farming and the effect of such methods on the profit of fish farmers in the Niger Delta region of Nigeria, Africa’s most populous country. Using cross‐sectional data obtained from 420 fish farmers from the region and applying multivariate probit and instrumental variable regressions, the study found that fish farmers have adopted a broad range of strategies to address climate risk and that these have significantly increased farmers’ profit. Our findings indicated important relationships between certain farm, socio‐economic and institutional characteristics and the adaptation actions. The study provides useful insight into factors that potentially encourage the adoption of livelihood‐enhancing climate risk adaptation strategies by fish farmers in the Niger Delta region and similar contexts.     

Factors influencing participation in the Nova Scotia Environmental Farm Plan Program

There is growing interest in Nova Scotia's Environmental Farm Plan (NS EFP) program among farmers and policy makers because of several reasons. First, effectiveness of standardized or uniform beneficial management practices in mitigating the negative environmental impacts from agriculture is limited by inherent heterogeneities in agricultural production systems. In addition, there is heightened interest in farmers generating ecological goods and services to society. This study investigates the determinants of participation in the NS EFP program. A discrete choice model of NS EFP participation was applied to a sample of 83 farmers (representing a 31% response rate). To increase relevance of the study to program administrators, the study also examined farmers’ use of various channels and sources of information on farm conservation practices. The most used sources of information on farm conservation practices include a mix of interpersonal sources and government agencies. Although online information (especially those available for free) appears to be gaining popularity in usage, overall, electronic and computer channels of information (especially radio and television) were used less compared with traditional channels of communicating farm conservation information (such as newsletters and agricultural magazines). Regression analysis suggests that farm characteristics (i.e., farm type, farm size, farm income) and farmer capacity variables (i.e., specialized training and knowledge from EFP program information sessions and workshops, and on-farm stewardship demonstrations) were significant determinants of environmental farm planning.     

Maximum likelihood estimation of stochastic volatility models

We develop and implement a method for maximum likelihood estimation in closed-form of stochastic volatility models. Using Monte Carlo simulations, we compare a full likelihood procedure, where an option price is inverted into the unobservable volatility state, to an approximate likelihood procedure where the volatility state is replaced by proxies based on the implied volatility of a short-dated at-the-money option. The approximation results in a small loss of accuracy relative to the standard errors due to sampling noise. We apply this method to market prices of index options for several stochastic volatility models, and compare the characteristics of the estimated models. The evidence for a general CEV model, which nests both the affine Heston model and a GARCH model, suggests that the elasticity of variance of volatility lies between that assumed by the two nested models.     

On the value relevance of SFAS No. 158

After considerable discussion and some controversy, Statement of Financial Accounting Standards No. 158 entitled, “Employers’ Accounting for Defined Benefit Pension and Other Postretirement Plans” was implemented in 2006. An important goal of these standards was to enhance financial reporting transparency for defined benefit pension plans (FASB, 2006). This study evaluates how well SFAS No. 158 achieved its objective. In particular, we compare the respective pre and post-SFAS 158 incremental value relevance of the balance sheet and income statement for firms with defined benefit pension plans (DBPP). Results suggest that the value relevance of book value (net income) increased (decreased) for DBPP firms after the implementation of SFAS No. 158.     

The purchase of components: Functional areas of influence

The Webster and Wind model of organizational buyer behavior enjoys considerable popularity. However, not all of its constructs and relationships among constructs have been validated by empirical research. The purpose of this study was to provide empirical evidence concerning the relationships between three of the model's critical constructs: buying center membership, purchase situation, and purchase phase. The relationships studied were variations in the perceived relative influence of different functional areas (e.g., production, marketing, purchasing, etc.) across three purchase situations and four purchase phases. The results of the study clearly indicate that the functional areas are generally perceived to have varying amounts of influence across both the purchase situation and purchase phase. These results have specific implications for developing effective industrial marketing strategies.     

Technological and financial approaches to risk management in agriculture: an integrated approach*

In the present paper, risk‐management problems where farmers manage risk both through production decisions and through the use of market‐based and informal risk‐management mechanisms are considered. It is shown that many of these problems share a common structure, and that a unified and informative treatment of a broad spectrum of risk‐management tools is possible within a cost‐minimisation framework, under minimal conditions on their objective functions. Fundamental results are derived that apply regardless of the producer's preference towards risks, using only the no‐arbitrage condition that agricultural producers never forego any opportunity to lower costs without lowering returns.     

Did decimalization hurt institutional investors?

We examine institutional trading costs around the move to penny size ticks in 2001 (i.e., decimalization). We find that overall trading costs declined, with improvements in most partitions across order size, firm size, and manager style. Improvements were most pronounced for orders that were executed over multiple days and for stocks where the minimum tick sizes were likely to have been binding. However, costs did increase for orders executed within a single day. The improvements we document contrast with changes accompanying the reduction of minimum ticks to sixteenths in 1997 though, in both cases, results suggest that more patient traders fare relatively better than those that demand immediacy.