A Comparison of EPI Sampling, Probability Sampling, and Compact Segment Sampling Methods for Micro and Small Enterprises

Finding an efficient method for sampling micro- and small-enterprises (MSEs) for research and statistical reporting purposes is a challenge in developing countries, where registries of MSEs are often nonexistent or outdated. This lack of a sampling frame creates an obstacle in finding a representative sample of MSEs. This study uses computer simulations to draw samples from a census of businesses and non-businesses in the Tshwane Municipality of South Africa, using three different sampling methods: the traditional probability sampling method, the compact segment sampling method, and the World Health Organization's Expanded Programme on Immunization (EPI) sampling method. Three mechanisms by which the methods could differ are tested, the proximity selection of respondents, the at-home selection of respondents, and the use of inaccurate probability weights. The results highlight the importance of revisits and accurate probability weights, but the lesser effect of proximity selection on the samples' statistical properties.     

A transactions data analysis of nonsynchronous trading

Weekly returns of stock portfolios exhibit substantial autocorrelation.Analytical studies suggest that nonsynchronous trading is capableof explaining from 5% to 65% of the autocorrelation. The varyingimportance of nonsynchronous trading in these studies arisesprimarily from differing assumptions regarding nontrading periodsof stocks. We simulate the effects of nonsynchronous tradingby sampling stock returns from a return generating process usingtransactions data to obtain the precise time of each stock'slast trade. We find that simulated weekly portfolio returnsexhibit autocorrelations that are roughly 25% that of theirobserved (CRSP) weekly returns.     

ASSESSING MONETARY POLICY IN SOUTH AFRICA IN A DATA‐RICH ENVIRONMENT

This paper examines the efficacy of monetary policy in the South African economy using a data‐rich framework. We use the Factor‐Augmented Vector Autoregressive (FAVAR) methodology, which contains 110 monthly variables for the period 1985:02‐2007:11. The results, based on impulse‐response functions, provide no evidence of the price puzzle observed in traditional Structural Vector Autoregressive analysis and confirm that monetary policy in South Africa is effective in stabilising prices. Unlike the traditional vector autoregressive approach, the FAVAR methodology allows further analysis of a large number of variables. Variables from real and financial variables react negatively to a contractionary monetary policy shock. Finally, we find evidence of the importance of a confidence channel transmission following a monetary policy shock.     

Shocks and rural livelihoods in the Okavango Delta,Botswana

This paper describes the impacts that three shocks in the Okavango Delta, Botswana, have had on rural livelihoods: the desiccation of river channels, animal diseases, and HIV/AIDS. Primary data was collected from five study areas, using formal questionnaire interviews and focus group discussions. The paper reveals the adverse effects on rural livelihoods. It describes the way households have been exposed to poverty and vulnerability and the various ways they have coped or adapted, such as by re-allocating their labour, liquidating their assets to cover medical expenses and funeral costs, reducing the area ploughed for crops, hiring labour, digging wells and switching from flood recession agriculture to dryland farming. The Botswana government has provided safety nets to help households cope, but this paper recommends that people's responses to these shocks should be taken into account in future policy and programme formulation.