Multivariate and Confirmatory Factor Analysis of Vehicular Emissions in Some Parts of Benin City, Nigeria

Abstract

Decline in air quality over the years has been linked to the growing rate of urbanization as well as an increase in the number of vehicles occasioned by the increased purchasing power of the people. Most of the pollutants emitted from vehicular activities have been observed to have adverse effects on individuals as well as the atmosphere. The focus of this study is to employ multivariate and confirmatory factor analysis (CFA) based on maximum likelihood estimation, to study the incidence of vehicular emissions in some parts of Benin city metropolis. Seven (7) georeferenced points (University of Benin main gate, Ekosodin junction, Agen Junction, Super D junction, Nitel junction, Okhunmwun junction and Oluku market junction) were used for data collection. Pollutants from vehicular emission, namely; dinitrogen oxide (NO2), carbon monoxide (CO) including the total radiation were monitored in the morning and evening for a period (7th July to 12th August, 2020) with the aid of portable toxic gas monitors and radiation alert meters. Other measured parameters of interest include maximum temperature and wind speed. To ascertain the quality of the data, selected preliminary analysis, namely; test of normality, test of homogeneity, outlier detection and reliability test were done. With a calculated partial Eta squared based on Pillai’s trace of 0.325, it was concluded that; there exist about 32.50 % variability among the dependent variables. Based on the CFA results, it was concluded that the hypothesis formulated for multivariate analysis of variance fits the sample data. Therefore, the alternate hypothesis was rejected and it was concluded that; the difference in the concentration of vehicular emission was as a result of change in temperature occasioned by time of measurement.