What do we mean when we talk about business angels? Some reflections on definitions and sampling

Early research on business angels recognized a couple of methodological obstacles that significantly have hindered knowledge accumulation about the phenomenon. In this article we will reflect upon these methodological obstacles with focus on definitional issues and sampling techniques. The purpose is to provide a framework that systemizes and inter-relates the variety of definitions within the field as well as to critically review the sampling techniques currently applied in the research field. We maintain that researchers need to make conscious definitional choices when conducting studies of informal investors and business angels, and argue that changing the unit of analysis from investor level to deal level can help to avoid definitional inconsistencies. Further, we suggest two alternative ways of creating high quality samples of business angels and informal investors - the random sample approach and the multi-sample approach. Both procedures reduce the sample bias and allow for longitudinal analysis which is argued to be essential in future research.