To explore the possibilities of public policies that balance comprehension of the privacy policy and willingness to use an app, we measured the treatment effects of displaying a summary of a privacy policy by a layered structure in different manners to vary the user’s load to browse the summary. A randomized controlled trial (RCT) was applied to 2060 Japanese online consumers with four treatment groups. The heterogeneity of the treatment effects was also measured by the time of using PC, trust in data protection rules, and the age groups. Users’ comprehension increased on average when treated with certain browsing loads. The user group with higher trust in the rules showed a higher increase. Users consuming longer time to use a PC tended to have lower comprehension levels compared to others after the treatment of a light browsing load, but those heavy PC users significantly increased their willingness to use when treated with heavier browsing loads. It was possible to improve comprehension without losing willingness to use.

The FTTH market for single-unit homes in eastern Japan area has allowed NTT East to maintain high market share, although there have been insufficient entries after its launch, and it has been less competitive to this day.

In this paper, we construct a hypothetical market model consisting of a dominant firm and a potential competitor. By analyzing the model in which the firms select the scenarios based in counterfactual assumption to maximize their own business value, we try to derive the mechanism of the actual market.

According to the analysis, the scenario chosen by NTT East squeezed the margins of a potential competitor and created a barrier to entry. On the other hand, NTT East’s scenario selection itself satisfied economic rationality and the competitive condition would be expected to improve through administrative regulation, therefor it is presumed that the situation did not make it necessary to change the scenario. As a result, we consider that competition became inactive because of insufficient opportunities for entry.