Does trading by small investors improve or deteriorate price efficiency?

In this study, we investigate the effect of minimum trade unit (MTU) reductions on the Korea Exchange (KRX) on price efficiency. The KRX switched its MTU from 10 shares to one share for high-price stocks twice, once in December 2004 and once in July 2006. The MTU changes were intended to attract small individual investors to the markets for high-price stocks. The MTU reductions on the KRX are different from previous cases of MTU reductions in other markets in that the KRX MTU reductions are not chosen by firms but are mandated by the exchange. Using these rare events, we examine whether the reductions in MTU and ensuing small investor participation enhance or deteriorate price efficiency. We examine three variables as indicators of price efficiency: return volatility, residual volatility, and the half-life of return volatility shock estimated from a generalized autoregressive conditional heteroskedasticity (GARCH) model. We find evidence of improved price efficiency from the 2004 event. For the 2004 sample, both return variance and residual return variance declined significantly after the MTU reduction. We also find evidence of reduction, albeit weak, in the half-life of volatility shock for the same sample. Meanwhile, for the 2006 sample, we do not find any changes in return variance or residual variance, nor do we find any evidence of change in the half-life of volatility shock. The difference in the patterns of changes in variables between the 2004 and 2006 events appears to be attributable to differences in the price levels of the stocks that were affected by the MTU changes and, consequently, a difference in reactions by small investors

A study of leadership development programme for gifted primary school students in South Korea

This thesis investigates leadership development in the gifted primary school students of South Korea. It ultimately aims to make suggestions toward the formulation and implementation of a model leadership gifted curriculum and programme specific to the Korean cultural and educational setting. The bases of the suggestions were assembled from three sources: literature pertaining to the relevant topics of the thesis, available leadership gifted curricula and programmes, and the perspectives of Korean gifted educators. The views of the Korean gifted teachers were investigated using mixed methods or methodological triangulation; the measurement instruments employed in this study were a tripartite questionnaire survey and complementary semi-structured interviews. Fifty Korean gifted teachers teaching at mainstream national and state primary schools, Centres for the Gifted, and specialised gifted schools partook in the questionnaire survey. Two Korean gifted teachers from mainstream state primary schools and the director of the Korean Educational Development Institute (KEDI) were interviewed to supplement the data collected through the questionnaires. The results illuminated the Korean gifted educational context and highlighted the lack and the need for leadership development for the gifted. Through the comprehensive review of the literature review, available curricula/programmes, and results of this study, final suggestions for a prospective leadership gifted curriculum and programme were made. Three main guidelines were proposed; firstly, a model of the prospective contents of leadership gifted education, named the Four Areas Leadership Model (FALM); secondly, the suggestions for the implementation of the FALM in a curriculum format; finally, the suggestions for the implementation of the FALM in a programme format. The FALM adopted the framework of Parker's (1983) Leadership Training Model, and its implementation as a programme was adapted from Renzulli's (1976, 1986) Enrichment Triad Model's implementation scheme which was considered appropriate to the Korean context

P-Cygni Type Lya from Starburst Galaxies

P-Cygni type Lya profiles exhibited in nearly half of starburst galaxies, both nearby and high-z, are believed to be formed by an expanding supershell surrounding a star-forming region. We apply the Monte Carlo code which was developed previously for static and plane-parallel medium to calculate the Lya line transfer in a supershell of neutral hydrogen which are expanding radially in a spherical bulk flow. We consider typical cases that the supershell has the Lya line-centre optical depth of $\tau_0=10^5-10^7$, a radial expansion velocity of $V_exp = 300 km/s, and the turbulence of b=40 km/s. We find that there appear a few emission peaks at the frequencies corresponding to (2N-1) V_exp, where the order of back scatterings N > 1. As V_exp -> b, the emergent profiles become similar to those for the static medium and the peaks are less prominent. We also investigate the effects of column density of the supershell on the emergent Lya profiles. We find that the number and the flux ratios of emission peaks are determined by interplay of$\tau_0$ and V_exp of the supershell. We discuss the effects of dust extinction and the implication of our works in relation to recent spectroscopic observations of starburst galaxies.Comment: 15 pages, 6 figures, submitted to MNRA