The missing effect of investments of firms in information and communication technologies on productivity is studied by various recent papers (e.g. Oliner and Sichels 1994, Landauer 1995, Brynjolfsson and Hitt 1996). Several explanations are given for this missing link. Our paper deals with two...

This paper studies if workers infer from correlation about causal effects in the context of the part-time wage penalty. Differences in hourly pay between full-time and part-time workers are strongly driven by worker selection and systematic sorting. Ignoring these selection effects can lead to...

Production functions provide a mapping from the firms' input quantity and productivity to output quantity. This mapping only generates unbiased estimates if input and output quality variation within and between observation units is accounted for. I review and classify state-of-the-art methods to...