Tornqvist-Theil indexes of outputs and inputs are constructed. These data are used to construct indexes of productivity growth over the postwar period. The productivity indexes can be derived from a flexible multioutput-multifactor representation of the structure of production constrained to constant returns to scale. Total factor productivity grew at an average annual rate of 1.75%, compared w...

This paper proposes an automatic expert system for accuracy crop row detection in maize fields based on images acquired from a vision system. Different applications in maize, particularly those based on site specific treatments, require the identification of the crop rows. The vision system is designed with a defined geometry and installed onboard a mobile agricultural vehicle, i.e. submitted t...

This paper studies concentration (i.e. inequality) aspects of the functions of Zipf and of Lotka. Since both functions are power laws (i.e. they are – mathematically the same) it suffices to develop one concentration theory for power laws and apply it twice for the different interpretations of the laws of Zipf and Lotka. After a brief repetition of the functional relationships between Zipf’s la...

This paper utilizes a rank-size function to investigate market concentration in lieu of well-known measures. For comparison, two measures were chosen: Theil’s entropy and the Herfindahl. The empirical results are based on premiums written for twelve lines of property and liability insurance. While the two concentration measures rank the lines for the level of concentration in almost complete un...

Article history: Received 16 June 2014 Received in revised form 19 September 2014 Accepted 21 September 2014 Available online 8 October 2014