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Wastewater treatment plants (WWTPs) that treat both foul and storm wastewater will experience significant pressure due to changing precipitation patterns and other geophysical parameters. Limited work has been done to understand the links between factors such as tidal and river levels, precipitation, and influent volumes to WWTPs. This paper analyses the variations of precipitation and their link with influent volumes. The study adopts a new approach to understand influent volume variations by taking into consideration, the combined and individual impacts of tidal and river levels in addition to precipitation; a topic that has not been examined in literature to date. It was found that, on a daily basis, precipitation, tidal elevation, and river levels were each statistically significant in explaining variations in daily influent volumes. On a monthly scale, the combined effects of average daily precipitation and the number of zero rainfall days contributed to the changes in influent volumes. Lastly, this paper proposed monthly pooled spatio-temporal analysis to understand the variable nature of monthly averaged daily influent volumes. These findings will help stakeholders in wastewater management with long-term planning and investment including responses to changing precipitation patterns and their impact on wastewater infrastructure.

This study proposes a model that enables us to investigate the multi-generation and the multi-country diffusion process simultaneously. Many former studies focus on only one of the dimensions since it is difficult to integrate both dimensions at the same time. Our proposed framework can explain both diffusion processes by capturing the common trend of multi-generation diffusion process and the country-specific heterogeneity. We develop the choice-based diffusion model by decomposing the choice probability of adoption into two components; the first component explains the individual country heterogeneity depending on the country-based variables while the second component captures the common trend of multi-generation diffusion process with the generation-based variables. We apply the model to 3G and 4G connections across 25 countries. Empirical result shows that it is not easy to use individual country level model for most countries due to the lack of data points. Our pooled model outperforms several individual country models according to the fitting and forecasting measures. We find that each country's market competitiveness and the market price affect the rate of diffusion and show that random effects of 3G and 4G are positively correlated. This framework provides the fine prediction capability even with few data points and valuable information for formulating policies on a new generation. • Multi-country and multi-generation diffusions can be simultaneously predicted. • Higher market competitiveness and lower market price increase the rate of diffusion for 3G and 4G connections. • The network effect increases the rate of diffusion for 3G and 4G connections. • Forecasting the multi-generation diffusion is possible even with few data points. [ABSTRACT FROM AUTHOR]

Simultaneity bias is an issue that do arise in most cases, when all variables in a model are interdependent. The study responds to this challenge by employing panel data models to analyse the effects of exports in SACU countries. The study applies stationary data estimation techniques to a sample of five (5) SACU countries over the period 1980-2016. The study finds that exports positively and significantly affect GDP per capita in SACU region. In addition, the fixed effects and random effects models clearly show that heterogeneity effects are significant, while the time effects are not significant in explaining the GDP per capita in the SACU region. This implies that country differences such as institutional, political and economic policy systems, among others, not included in the models are significant in explaining GDP per capita in SACU region. Finally, the study finds that SACU countries are enjoying increasing returns to scale. On the policy front, it should be noted that the longstanding trade liberalisation and trade openness agendas of SACU have had a significant impact on economic growth and this has led to an upsurge in exports. Therefore, the SACU region, must focus more on structural transformation which involves moving their specialisation patterns to more sophisticated goods and services in order to bolster their comparative advantage in international markets which affects economic growth through exports. [ABSTRACT FROM AUTHOR]

The principal objective of the study was to assess the direct effect of exports on economic growth for five selected countries in Southern Africa. Previous studies that detail the effect of exports on economic growth for the five selected countries are virtually not in existence in both empirical and theoretical literature that the study reviewed, and hence research opportunities do emerge for further examination. The study applies panel data econometric techniques to analyse the effects of exports on economic growth for the five selected countries covering the period 1980 to 2016. The study finds that exports positively and significantly affect gross domestic product per capita in the five countries assessed. The results also indicate that heterogeneity effects are significant, while the time effects are not significant in explaining the relationship between exports and economic growth in selected countries. This implies that country differences such as institutional, political and economic policy systems, amongst others, not included in the models are significant in explaining gross domestic product per capita in the five countries. The study is a source of information to scholars. The study provides some explanations to the links between exports and economic growth. [ABSTRACT FROM AUTHOR]

This paper presents a study that examines two waves of travel survey data through a pooled model structure. The pooled model structure provides a means to take advantage of multiple data sources which will lead to a better estimate and understanding of travel behavior. In particular, it accounts for the difference in data variance and therefore allows for the comparison of the true impacts of the model parameters on traveler's tour-making behavior. Larger variance is found in the 1998 data than in the 2010 data. Comparison between model parameters reveals significant behavioral changes among several socio-economic and demographic groups. In terms of common variables, the magnitude of the coefficient values has generally decreased, which conforms to the overall decreasing trend in traveling. Overall, the model equality tests indicate that the models developed based on the two data sources do not have equal taste parameters, thus the transferability hypothesis is rejected. The results of this study are expected to have implications for the application of models based on cross-sectional data, especially over long time periods. [ABSTRACT FROM AUTHOR]

An optimal Capital Structure is the main decision for any business management to be taken for persistent growth and wealth maximization of the shareholders. The study is conducted to investigate firm-level characteristics and macroeconomic determinant that influence Capital Structure Decision of insurance industry in Pakistan from the study period of 1999 to 2013. The Hausman's specification and Breusch, and Pagan Lagrange Multiplier Test are employed to find out the most appropriate models among fixed effects, random effect and pooled regression model. The tests confirm that pooled regression model and fixed effect model are the most prominent models for the study. In addition, the findings of the study reveals that profitability and business risk are inversely but significantly related with debt across both estimation techniques. The negative relationship of profitability and business risk with debt confirm Pecking Order Theory. However, tangibility of assets and inflation rate are positive and statistically significantly effect on Leverage, which supports Trade off Theory. Inflation rate is significant on pooled regression model however fixed effect estimation give insignificant result of inflation rate. Growth of the firm is also insignificant factor of Capital Structure in insurance sector of Pakistan across both regression models. According to the best knowledge of the authors, this is the first study, which considers both financial and economic variables of capital structure in insurance sector. The study is recommended that senior-mangers can make an optimal- mix of debt and equity by selecting endogenous (i.e. profitability, growth, tangibility and business risk) and exogenous factor like inflation of insurance sector of Pakistan. [ABSTRACT FROM AUTHOR]

This paper presents an investigation of the temporal evolution of commuting mode choice preference structures. It contributes to two specific modelling issues: latent modal captivity and working with multiple repeated crossectional datasets. In this paper latent modal captivity refers to captive reliance on a specific mode rather than all feasible modes. Three household travel survey datasets collected in the Greater Toronto and Hamilton Area (GTHA) over a ten-year time period are used for empirical modelling. Datasets collected in different years are pooled and separate year-specific scale parameters and coefficients of key variables are estimated for different years. The empirical model clearly explains that there have been significant changes in latent modal captivity and the mode choice preference structures for commuting in the GTHA. Changes have occurred in the unexplained component of latent captivities, in transportation cost perceptions, and in the scales of commuting mode choice preferences. The empirical model also demonstrates that pooling multiple repeated cross-sectional datasets is an efficient way of capturing behavioural changes over time. Application of the proposed mode choice model for practical policy analysis and forecasting will ensure accurate forecasting and an enhanced understanding of policy impacts. [ABSTRACT FROM AUTHOR]