Journals

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An academic or scholarly journal is a periodical publication in which scholarship relating to a particular academic discipline is published in University of Ghana. Academic journals serve as permanent and transparent forums for the presentation, scrutiny, and discussion of research. They are usually peer-reviewed or refereed. Listed here are Journals from the University of Ghana.

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    Application of the Hypergeometric Model in Electoral Disputes Settlement
    (Ghana Social Science Journal, 2016) Somaayin, N.H.; Tibie, K.; Doku-Amponsah, K.
    Judges or members of Election Management Bodies (EMBs) of many less developed democracies are often faced with reviewing electoral complaints and coming out with a decision that is acceptable to all parties involved. Some judges have ruled for complete cancellation of all votes in the affected polling stations. Where the electoral irregularities are widespread, it is very difficult to declare a winner without incurring the additional cost of a re-run. In this article, we use the hypergeometric model to provide an alternative method to direct cancellation or proportional deduction approach used by many EMBs in the settlement of electoral disputes. To be specific, we provide a bound on the margin of victory when either a re-run or fresh election is not necessary to determine the winner of the polls, i.e., the non-overturn condition. We use this method to investigate whether or not the decision by the Electoral Commission of Ghana to declare the NDC candidate the winner of the presidential run-off of 2008 is statistically correct given the data available to the Commission on the day to declare the winner. Using this approach in the review of electoral complaints could help developing nations to save some money for development that would otherwise have been spent on election re-runs
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    Portfolio Optimization Using Minimum Variance Line Approach: A Case Study of the Social Security and National Insurance Trust
    (Ghana Social Science Journal, 2017-12) Nkum, N.; Lotsi, A.; Chapman-Wardy, C.; Doku-Amponsah, K.
    The main motive of investors around the globe is to invest in assets with the idea of maximizing the return with a minimum risk of investment. The management of investment portfolio requires carefully selecting various assets to invest in, as well as managing the proportions of funds to be channeled into a particular investment. The data used in this study was obtained from Social Security and National Investment Trust (SSNIT) covering a five-year period spanning from 2010 to 2014. The data comprised of the prices of Investment Properties (IVP), Investment to Maturity (IVM) and Loans Receivable (LR), out of which the expected return of each asset, the standard deviation (SD) of each asset, the correlation between assets and the covariance between assets are computed. The methodology used here was the minimum variance line approach proposed by Harry Markowitz. The model allowed us to assign weights to various investment classes by transposing the expected returns and risk associated with them. The result showed that, as the expected return of the portfolio increases the various percentage weight to be invested in IVP and LR increase whilst that of IVM decreases. The portfolio standard deviation or risk on the other hand also increases with increasing portfolio expected returns
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    Estimating Exceedance Probability of Extreme Water Levels of the Akosombo dam
    (Science and Development, 2017) Ocran, E.; Doku-Amponsah, K.; Nortey, E.N.N.
    The Akosombo dam is a major source of electric energy in Ghana. Considering the current increase in the demand for electricity in the country, where such an increase in demand implies more pressure on the dam, it is of key interest to study the tail behaviour of the water levels of the dam. Such a study is important because the level of water in the dam determines the amount of electricity generated. The study employed the Univariate Extreme Value Theory to model the monthly maximum and minimum water levels of the dam. The Generalized Extreme Value Distribution was fitted to the data and the Maximum likelihood estimation method was employed to estimate the model parameters. The study indicated that, the water levels cannot fall below 226.00ft which is the critical water level of the Akosombo dam. It further showed that, the lowest ever level of water the dam can attain is 226.69ft and the highest 279.07ft. The study also found that, though the water cannot fall below the critical level, there was evidence of its falling below the minimum operation head.