We study the relation between formal incentives and social exchange in organizations where employees work for several managers and reciprocate to a manager's attention with higher effort. To this end we develop a common agency model with two-sided moral hazard. We show that when effort is...

This discussion paper has resulted in a publication in the <I>Journal of Economic Psychology</I>, 31(4), 676-686.<P> We study optimal incentive contracts for workers who are reciprocal to management attention. When neither worker's effort nor manager's attention can be contracted, a double moral-hazard...</p></i>

Some 2000 years ago, the average annual distance a person would normally travel, was approximately 500 km. The action radius of most people remained rather stable, but it rose gradually after the industrial revolution to some 1820 km (by car, bus, railway or aircraft) in the year 1960. Then, a...

See also the article in <I>Cities</I> (2013). Volume 30, pages 59-67.<P> This paper introduces a new measure to approach the accessibility of places in the frame of the digital economy. Information and Communication Technologies (ICTs) and the Internet are not equally spread around places and this...</p></i>

This paper discusses the value that data from mobile phone providers can bring into urban analysis. The novel argument is that the pervasiveness of mobile phone telephony has transformed mobile phones from a communications device to a tool for socio-spatial research. Put simply, mobile phone...