Relatedness of decisions in business services outsourcing

The literature of service outsourcing is mainly focused on case studies or specific service activities. However, there is no evidence about the pattern of relatedness among outsourcing of services. This paper analyses this issue by a relatedness index previously applied in the framework of product and technological diversification. The index is applied to analyse the degree of relatedness for outsourcing decisions among an array of fourteen services in a large data set of Spanish manufacturers in 1990-2006, detecting four time-constant clusters. An econometric analysis tests the alternative explanations about this pattern of joint decisions, based on shared knowledge and on workers' expertise.