Selection bias in innovation studies: a simple test.

The study of the innovative output of firms often relies on a count of patents filed at one single office of reference such as the European Patent Office (EPO). Yet, not all firms file their patents at the EPO, raising the specter of a selection bias. Using a novel dataset of the whole population of patents by Belgian firms, we show that the singleoffice count results in a selection bias that affects econometric estimates of innovation production functions. We propose a methodology to evaluate whether estimates that rely on the singleoffice count are affected by a selection bias.innovation production function; patent; R&D; selection bias;

Debt Financing of High-growth Startups

We study the business model of venture debt firms, specialized institutions that provide loans to high-growth startups. Venture debt represents an apparent contradiction with traditional debt theory since startups have negative cash flows and lack tangible assets to secure the loan. Yet, we estimate that the U.S. venture debt industry provides at least one venture debt dollar for every seven venture capital dollars invested. We aim to provide the first empirical evidence on the determinants of the lending decision. Building on existing field interviews and case studies, we design a choice experiment of the lending decision and conduct experiments with 55 senior venture lenders. We find support for the hypothesis that backing by venture capital firms substitutes for startups’ cash flow. Furthermore, we illustrate the signaling effect of patents and their role as collateral to facilitate the lending decision.Venture capital; startups; patents

An Introduction to the Patstat Database with Example Queries

This paper provides an introduction to the Patstat patent database. It offers guided examples of ten popular queries that are relevant for research purposes and that cover the most important data tables. It is targeted at academic researchers and practitioners willing to learn the basics of the database.Comment: To appear in the Australian Economic Revie

Selection bias in innovation studies : a simple test

The study of the innovative output of firms often relies on a count of patents filed at one single office of reference such as the European Patent Office (EPO). Yet, not all firms file their patents at the EPO, raising the specter of a selection bias. Using a novel dataset of the whole population of patents by Belgian firms, we show that the single-office count results in a selection bias that affects econometric estimates of innovation production functions. We propose a methodology to evaluate whether estimates that rely on the single-office count are affected by a selection bias

The R&D-patent relationship: An industry perspective

This paper re-visits the empirical failure to establish a clear link between R&D efforts and patent counts at the industry level. It is claimed that the “propensity-to-patent” concept should be split into an “appropriability propensity” and a “strategic propensity”. The empirical contribution is based on a unique panel dataset composed of 18 industries in 19 countries over 19 years. The results confirm that the R&D-patent relationship is affected by research productivity, appropriability propensity and strategic propensity factors. The observed increase in the propensity to file for patents is much stronger for supranational (that is, triadic or regional) patents than for priority filings, suggesting that the current patent hype is essentially the result of a globalization phenomenon.Propensity to patent; strategic propensity; appropriability; research productivity

Do Patents Enable Disclosure?:Evidence from the Invention Secrecy Act

This paper provides empirical evidence suggesting that patents may facilitate knowledge disclosure. The analysis exploits the Invention Secrecy Act, which grants the U.S. Commissioner for Patents the right to prevent the disclosure of new inventions that represent a threat to national security. Using a two-level matching approach, we document a negative and large relationship between the enforcement of a secrecy order and follow-on inventions, as captured with patent citations and text-based measures of invention similarity. The effect carries over to after the lift of the secrecy period, suggesting a lost generation of inventions. The results bear implications for innovation and intellectual property policy

Role of vitamin D in HIV infection

La vitamine D possède des propriétés sur le métabolisme phosphocalcique mais aussi dans diverses pathologies telles que les maladies auto-immunes, les cancers, les maladies cardio-vasculaires, l’excès de poids ou encore certaines infections. Nous nous intéressons ici aux relations frappantes qui existent entre la vitamine D et le VIH. Cette hormone joue assurément un rôle important dans l’infection par le VIH, tant au niveau squelettique qu’au niveau de l’évolution de la maladie elle-même. Nous remarquons en effet qu’un déficit en vitamine D est très souvent associé à l’infection par le VIH. De plus, un taux indétectable de cette hormone chez les patients séropositifs est associé à une infection cliniquement plus avancée et à une mortalité accrue. Ainsi, le déficit en vitamine D doit être considéré comme un cofacteur important de la progression de l’infection par le VIH. En effet, la vitamine D augmente l’activité des macrophages, entre autres via le processus d’autophagie, ce qui permet d’inhiber l’infection par le VIH-1. Nous parlerons ensuite de l’impact de certains traitements antirétroviraux sur l’altération du métabolisme de la vitamine D. Nous évaluerons enfin le bénéfice d’une supplémentation en vitamine D chez ces patients.Peer reviewe