Halvorsen has a PhD degree (Dr.Polit.) from the Universitetet os Oslo. She has worked on a wide number of topics within environmental and resource economics. The main fields of work in recent years have been household energy consumption, distribution analyzes linked to energy expenditure, fire risk in Norwegian coastal heathland and resource rent in fisheries. She has also previously worked with households' recycling behavior and analyzes of fear of dental treatment, as well as cost benefit analyzes and valuation studies, which is the topic of Halvorsen's doctorate. Halvorsen has also worked extensively with methods for aggregating microbehaviour. Consistent with all Halvorsen's research are microeconometric behavioral analyzes on various topics.