A model of firm innovation illustrates the effects of the threat of imitation and product varieties on a representative firm's decision to invest in research and development to produce new product varieties. The model motivates two empirical questions: (1) Is research and development partially...

"It is so widely recognized that innovation is a key driver of economic growth that it is cliche to say so. This article studies product innovation by firms with data from 68 countries, covering more than 25,000 firms in eight manufacturing sectors. The author assesses the predictions of...

"It is so widely recognized that innovation is a key driver of economic growth that it is cliche to say so. This article studies product innovation by firms with data from 68 countries, covering more than 25,000 firms in eight manufacturing sectors. The author assesses the predictions of...

"This paper examines the link between sectoral concentration and overall performance in the search for on-the-frontier innovations, inside-the-frontier innovations, and export booms. It extends the literature by increasing country coverage and the types of search processes considered, and by...