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In this paper the concepts of general, target and accessible population are explained in response to misconceptions and controversies associated with them, and the fact that the relationships between them have not been explained in the context of qualitative enquiry in any formal study. These concepts are discussed in this study based on a general scenario. We basically attempt to explain the importance of specifying the general, target and accessible populations in a qualitative study when the study population is large. The study depicts how the research goal, contexts and assumptions can dictate the content and concentration of the target and accessible population in qualitative inquiry. It also poses the sampling implications of our explanations and highlights the stages and levels of what we refer to as population refinement.

This paper models and forecasts volatility (conditional variance) on the Ghana Stock Exchange using a random walk (RW), GARCH(1,1), EGARCH(1,1), and TGARCH(1,1) models. The unique 'three days a week' Databank Stock Index (DSI) was used to study the dynamics of the Ghana stock market volatility over a 10-year period. The competing volatility models were estimated and their specification and forecast performance compared with each other, using AIC and LL information criteria and BDS nonlinearity diagnostic checks. The DSI exhibits the stylized characteristics such as volatility clustering, leptokurtosis and asymmetry effects associated with stock market returns on more advanced stock markets. The random walk hypothesis is rejected for the DSI. Overall, the GARCH (1,1) model outperformed the other models under the assumption that the innovations follow a normal distribution.

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