The research contained in the theoretical side Mbgesan, in the first part, has been the research methodology by showing the importance of research, which confirmed the account the new addition to the specialists and researchers in this field. The research problem can be summarized in the efficiency of this method in a manner comparable two-stage least squares for the combined effects of fixed periods and groups, as well as the goal of the research and its premises and the nature of the variables used and where they overlap.
In the second part, the researchers introduced the concept of system of simultaneous equations for the method of combining CT data and time series, using fixed effects for the periods and groups once and use them without a second time. Also has been diagnosed conditions of the model used in the analysis, which includes the police rank and order in addition to illustrate the use of least squares method of two-stage built-in appreciation of the data used in the research as well as view to test the fixed effects for each of the groups and periods.
The third section, results of the assessment were presented to the system of simultaneous equations used in the research and for the period (1990-2005), disaggregated by estimation method and the type of the function of each sector (public, mixed, cooperative, private) separately.
Finally, the researchers demonstrate the conclusions and recommendations reached by the research