Purpose: The purpose of this study is to compare the production efficiencies and frontiers differences of oil-producing countries (OPCs) in four inter-governmental organizations (IGOs) in the international petroleum industry with the aim of providing such countries understanding of group...

Purpose: The purpose of this paper is to re-examine the weak form efficiency of five African stock markets (South Africa, Nigeria, Egypt, Ghana and Mauritius) using various tests to assess the impact of non-linearity effect and thin trading which are prevalent in African markets on market...

Purpose: The purpose of this study is to examine efficiency differences among petroleum firms based on their ownership status, with the aim of helping these firms understand how specific levels of state-ownership affects efficiency and to bring new perspective to the ownership-performance...

Purpose: The purpose of this paper is to investigate the factors that tend to influence credit union efficiency, specifically examining cost efficiency (CE) and technical efficiency. Design/methodology/approach: Using a two-stage method, the authors first estimate CE using Tones’ SBM data...