Some observations on the brain and behaviour of the goldfish, Carassius auratus

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The Kaipara story: a closer look at the benefits of working together, the evolution of a federation of aquaculture self-help groups and a one-stop aqua shop in rural West Bengal

What is special about Kaipara is that most recently, they have founded a federation of Self-Help Groups that work together to develop their own support network and to draw in the support of others. This is a sophisticated ‘home-grown’ support infrastructure that is the subject of this story. (Pdf contains 8 pages)

Transmission overhaul and replacement predictions using Weibull and renewel theory

A method to estimate the frequency of transmission overhauls is presented. This method is based on the two-parameter Weibull statistical distribution for component life. A second method is presented to estimate the number of replacement components needed to support the transmission overhaul pattern. The second method is based on renewal theory. Confidence statistics are applied with both methods to improve the statistical estimate of sample behavior. A transmission example is also presented to illustrate the use of the methods. Transmission overhaul frequency and component replacement calculations are included in the example

Bayesian methods of astronomical source extraction

We present two new source extraction methods, based on Bayesian model selection and using the Bayesian Information Criterion (BIC). The first is a source detection filter, able to simultaneously detect point sources and estimate the image background. The second is an advanced photometry technique, which measures the flux, position (to sub-pixel accuracy), local background and point spread function. We apply the source detection filter to simulated Herschel-SPIRE data and show the filter's ability to both detect point sources and also simultaneously estimate the image background. We use the photometry method to analyse a simple simulated image containing a source of unknown flux, position and point spread function; we not only accurately measure these parameters, but also determine their uncertainties (using Markov-Chain Monte Carlo sampling). The method also characterises the nature of the source (distinguishing between a point source and extended source). We demonstrate the effect of including additional prior knowledge. Prior knowledge of the point spread function increase the precision of the flux measurement, while prior knowledge of the background has onlya small impact. In the presence of higher noise levels, we show that prior positional knowledge (such as might arise from a strong detection in another waveband) allows us to accurately measure the source flux even when the source is too faint to be detected directly. These methods are incorporated in SUSSEXtractor, the source extraction pipeline for the forthcoming Akari FIS far-infrared all-sky survey. They are also implemented in a stand-alone, beta-version public tool that can be obtained at http://astronomy.sussex.ac.uk/$\sim$rss23/sourceMiner\_v0.1.2.0.tar.gzComment: Accepted for publication by ApJ (this version compiled used emulateapj.cls

Telecommunications productivity, catch-up and innovation

This study examines telecommunications productivity, technological catch-up and innovation in 74 countries for the period 1991-1995. A summary of partial productivity indicators is presented, and total factor productivity (TFP) growth is calculated using the Malmquist productivity change index. Decomposition of the Malmquist index provides preliminary evidence that developing countries can enhance productivity through catch-up. An econometric model is estimated that relates innovation to market size and two measures of market structure, viz., market concentration and private ownership. Model estimates support the Schumpeterian hypothesis that market size is conducive to innovation. However, the hypothesis that concentration (the dominant carrier's share of international message telephone service (IMTS) traffic) is positively related to innovation is rejected. Finally, the model suggests that increased private ownership of the dominant local-exchange carrier can enhance innovation.Catch-up; innovation; market structure; productivity; telecommunications

Market structure, competition, and pricing in United States international telephone service markets

Abstract—Several national governments argue international telephone prices are high because of asymmetric competition and inefficiencies in the accounting arrangements that govern the telecommunications services trade. This paper develops a model of U.S. international telephone pricing that allows for the accounting rate system and contains market-structure variables for both the U.S. and foreign ends of bilateral markets. Model estimation is on 39 bilateral telephone markets from 1991 through 1994. Parameter estimates reveal that settlement rates, market concentration, competition at either end of the bilateral market, and ownership are significant determinants of prices. These findings support initiatives promoting accounting-rate reductions and increased competition.United States international telephone service markets

Some economic and social aspects of residential internet use in Australia

This study constructs a profile of the representative Australian residential Internet user from data obtained from a web-based survey. Survey data indicate the representative user is male, 20 to 40 years of age, highly educated, uses the Internet 8 hrs per week for e-mail and FTP, and has a monthly bill of AUD32. Anordered-logit model relates Internet use to price, sociodemographic and connection capacity variables. Model estimates show the probability of higher Internet use is greater for middle-income households, but declines with age of the user. Policy may be required to enhance access to lower-income groups, and to inform the elderly of the potential capabilities of the new technology. Further, model estimates suggest that Australian Internet subscribers prefer flat-rate pricing (or a combination of flat-rate and usagesensitive pricing) over usage-sensitive pricing schemes. This result is consistent with Australian consumer attitudes toward local telephone and mobile cellular pricing.Residential internet use in Australia, economic and social aspects

CEE telecommunications investment and economic growth

The antiquated state of the telecommunications network in the transitional economies of Central and Eastern Europe has been identified by the OECD (1993) and the ITU (1994) as a significant impediment to regional productivity, international competitiveness and trade performance. This situation suggests that the upgrading and extension of the telecommunications network should be a priority objective for policy-makers in order to facilitate growth. This paper empirically examines the relationship between gross fixed investment, telecommunications infrastructure investment and economic growth for a sample of transitional economies in Central and Eastern Europe. In particular, the paper focuses on empirically determining the direction of influence, and timing, between investment and growth.Economies in transition; Investment and growth; Telecommunications infrastructure