Hyperbolic discounting and condom use
German researchers wanted to understand why demand for condoms is low in rural areas in undeveloped countries. One theory is that access to free, generic condoms at clinics crowded out demand for branded condoms that cost money. They set up a study in which different villages were offered branded condoms at different, subsidized prices. They found that people were receptive to buying condoms, but were very price sensitive. Furthermore, convenience was important, as people reported that they chose to buy condoms because the clinics at which free condoms were available were far away. This suggests that condom usage can be increased if they are subsidized and placed conveniently.