FROM MAIZE TO HAZE: AGRICULTURAL SHOCKS AND THE GROWTH OF THE MEXICAN DRUG SECTOR

Understanding how economic incentives affect illegal drug production is essential for crafting policies in response to the international drug trade. Policymakers typically face a choice between two strategies: targeting criminal groups via law enforcement, and offering producers incentives to engage in alternate activities. Yet, little is known about how the returns to alternate legal activities affect drug supply. We contribute to this literature by examining how shocks to legal commodity prices affect the drug trade in Mexico. Our analysis exploits exogenous movements in the Mexican maize price stemming from weather conditions in US maize‐growing regions, as well as exports of other major maize producers. Using data on over 2200 municipios spanning 1990–2010, we show that lower prices differentially increased the cultivation of both marijuana and opium poppies in municipios more climatically suited to growing maize. We also find impacts on downstream drug‐trade outcomes, including drug cartel operations and killings perpetrated by these groups. Our findings demonstrate that maize price changes contributed to the burgeoning drug trade in Mexico, and point to the violent consequences of an expanding drug sector.     

Dynamic Pricing in e‐Services under Demand Uncertainty

High volatility of the e‐services market, due to increasing competition, low life cycle of products, and easy availability of information about competing service offerings to customers, makes the demand for service offerings quite uncertain. Revenue management in such markets calls for real‐time techniques to learn the demand and its dependence on both the price and the service level associated with the service offering. We assume firms reply on exploratory approaches for demand estimation, in which firms experiment with different service offerings in order to simultaneously learn the demand while doing business. Such exploration and learning process can be costly without supervision. As reported by Rothschild (Journal of Economic Theory, 9 185‐202, 1974), traditional Bayesian dynamic control approaches may conclude with suboptimal offerings. We propose a novel demand learning approach that is guaranteed to converge to the optimal offering. The approach combines simulated annealing algorithm with Bayesian learning. We further present intelligent techniques that adaptively reduce the effort of exploration on suboptimal service offerings so as to improve the long‐run average profit.     

Ordinary least squares and Stein-rule predictions in regression models under inclusion of some superfluous variables

This article considers a misspecified linear regression model in which misspecification relates to the inclusion of some explanatory variables. Assuming the distribution of disturbances to be not necessarily normal, this paper investigates the efficiency properties of predictions arising from ordinary least squares and Stein-rule when the aim is to predict either the actual value or the mean value of the study variable.     

Stein-rule estimator under inclusion of superfluous variables in linear regression models

Stein-rule estimation is a well-known method to improve the unbiased OLSE in the sense of smaller Mean-Square-Error. The paper is investigating the behaviour of this efficiency relation in case of misspecification of the linear model caused by inclusion of superfluous variables     

Implementing an improved inventory control system in a small company: a case study

The paper presents the implementation of an improved inventory management control system in a small company. The project took place at Trojan Mine, a company involved in mining mineral resources. Firstly, a conceptual framework for the design of an inventory control management system is developed. Secondly, a very effective user-friendly inventory control tool for determining the category A items was developed using EXCEL spreadsheet; a tool that is an asset to the company since it can be used in future. Finally, key performance indicators were also established to give benchmark to operations. The improved inventory control management system developed is found to offer improvement to the performance of the company since capital tied up in overstocking items of high annual usage value is released.     

Estimating hybrid frequency moments of data streams

We consider the problem of estimating hybrid frequency moments of two dimensional data streams. In this model, data is viewed to be organized in a matrix form (A _i,j )_1≤i,j,≤n . The entries A _i,j are updated coordinate-wise, in arbitrary order and possibly multiple times. The updates include both increments and decrements to the current value of A _i,j . The hybrid frequency moment F _p,q (A) is defined as \(\sum_{j=1}^{n}(\sum_{i=1}^{n}{A_{i,j}}^{p})^{q}\) and is a generalization of the frequency moment of one-dimensional data streams.We present the first \(\tilde{O}(1)\) space algorithm for the problem of estimating F _p,q for p∈[0,2] and q∈[0,1] to within an approximation factor of 1±ε. The \(\tilde{O}\) notation hides poly-logarithmic factors in the size of the stream m, the matrix size n and polynomial factors of ε ^?1. We also present the first \(\tilde{O}(n^{1-1/q})\) space algorithm for estimating F _p,q for p∈[0,2] and q∈(1,2].     

Rethinking melas as subaltern spaces: Pardhan blacksmiths and some aspects of ‘caste-passing’ in fairs, 1872–1931

Nineteenth-century melas (fairs) were evanescent public spaces that facilitated anonymity and unplanned encounters between castes, classes, men and women. By recognizing caste-passing in various mela clusters, historians gain insights into a range of subaltern debates about caste. Caste-passing involved lower caste adoption of the accouterments of upper castes and threatened social hierarchy. Opaque to police, associational life within fairs signified a society undergoing transformation. The figure of the Pardhan blacksmith embodied the unknowable fair-going crowd. Hailing from an adivasi (indigenous) community in the Central Provinces of India, these blacksmiths attracted police notice. Pardhan blacksmiths deployed their skills towards manufacturing imitation gold; at the fair they passed off as members of upper castes. For the police, Pardhan caste-passing within fairs threatened to unravel taxonomies of tribe and caste, region and religion. It was at the fair that hounded and persecuted Pardhan blacksmiths found some respite from the theft of their lands and labour. Through an analysis of caste-passing, a social history emerges of nineteenth-century fairs in colonial India that foregrounds experiences of those fairgoers who were members of ‘criminal tribes’ persecuted by colonial police, and the plebeian multitude that mingled in melas and participated in anti-caste debates.