This study aims to evaluate the effect of computerized tax services in improving tax performance by moderating governance principles in Jordanian tax income departments. The study is based on a questionnaire distributed to income tax auditors, who were chosen by the simple random sampling method, so that 170 questionnaires were subjected to statistical analysis. The study models were formulated in the form of simple and multiple regression equations to test the hypotheses of the study, in addition to relying on One Sample T-test to calculate the mean of questionnaire answers. The most prominent research results is that the application of tax governance principles through the provision of computerized tax services is reflected in the increase in confidence between taxpayers and income tax departments, the efficiency of tax performance, and tax proceeds. Also, the study pointed out the importance of the income tax departments to prepare strategic plans regarding the development and the follow-up of modern technologies related to computerized tax services. It especially regards linking and collecting tax from taxpayers such as via electronic tax payment and collection system, in order to ensure the speed of completion, accuracy of calculation, and raising the efficiency of tax performance.

The study aims to compare the effects of employing investment deposits (joint and specified investment deposits) in Islamic banks, and investment deposits (term deposits and deposits with notification) at conventional banks, on shareholders’ profitability, represented by the earnings per share (EPS), in light of operational profits as a controlling variable. Data related to the study variables was collected from the annual financial reports published by the study sample banks, during the period (2009-2018). The study relies on multiple regression to test the hypotheses of the study. The high adjusted R² to explain the change in EPS for Islamic banks model as compared to conventional banks, is a result of the high difference between investment deposits (specified and joint) at Jordanian Islamic banks and investment deposits (term deposits and deposits with notification) at Jordanian conventional banks. The study found that it is important for the managements of Islamic banks to adopt a uniform method to combine speculative funds, in order to develop and improve shareholders’ profitability. The study recommended Islamic banks to follow practical, methodological and transparent approaches to calculate the rates of Murabaha profit margins between shareholders and depositors, while also taking into consideration some of the issues which could be harmful for the competition between Islamic and conventional banks.