The existence of some differences in the results obtained from varying clustering k-means algorithms necessitated the need for a simplified approach in validation of cluster quality obtained. This is partly because of differences in the way the algorithms select their first seed or centroid either randomly, sequentially or some other principles influences which tend to influence the final result outcome. Popular external cluster quality validation and comparison models require the computation of varying clustering indexes such as Rand, Jaccard, Fowlkes and Mallows, Morey and Agresti Adjusted Rand Index (ARIMA) and Hubert and Arabie Adjusted Rand Index (ARIHA). In literature, Hubert and Arabie Adjusted Rand Index (ARIHA) has been adjudged as a good measure of cluster validity. Based on ARIHA as a popular clustering quality index, we developed OsamorSoft which constitutes DNA_Omatrix and OsamorSpreadSheet as a tool for cluster quality validation in high throughput analysis. The proposed method will help to bridge the yawning gap created by lesser number of friendly tools available to externally evaluate the ever-increasing number of clustering algorithms. Our implementation was tested alongside with clusters created with four k-means algorithms using malaria microarray data. Furthermore, our results evolved a compact 4-stage OsamorSpreadSheet statistics that our easy-to-use GUI java and spreadsheet-based tool of OsamorSoft uses for cluster quality comparison. It is recommended that a framework be evolved to facilitate the simplified integration and automation of several other cluster validity indexes for comparative analysis of big data problems.

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Organizations reduced their tax revenue through tax evasion and avoidance, thereby affecting the economic growth of the country. In an attempt to further stress this assertion, this study aims to empirically examine the effects of tax revenue on economic growth in Nigeria. Tax revenue was a proxy with PPT, CIT, VAT and CTD, while economic growth was proxy with GDP. Ex post facto research design was employed, while time series quarterly data were collected from the statistical bulletins of CBN and FIRS for 10 years (2011-2020). Data collated were analyzed using descriptive analysis, unit root test, bounds cointegration test and ARDL. The findings revealed that PPT, CIT, VAT and CTD had positive insignificant effects on economic growth. The study concluded that tax revenue had insignificant effects on the economic growth of Nigeria and therefore, recommended that proper tax audit should constantly be carried out to reduce tax evasion and avoidance.

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Stock market investors are regarded as rational being, but during stock market liquidity, investors tend to exhibit herding behaviour. Several factors affect stock market liquidity, but the liquidity of Conglomerate and Consumer goods sectors may not be obvious. This study examined the impact of stock market liquidity on herding behaviour of investors in Nigerian stock market with focus on Conglomerate and Consumer goods sectors. Monthly data of stock returns and market capitalization for fifteen years from 2001-2015 were used and 28 companies' stocks from both sectors were considered. OLS model was used to determine the impact, existence and extent of herding behavior in these sectors. The results showed that stock market liquidity had impact on herding behaviour in both sectors and during high and low market liquidity, there is an evidence of herding behaviour which is not statistically significant in Conglomerate sector compared to Consumer goods sector. The study recommended that NSE should make information available to all market participants in order to boost their confidence in making their own decisions.