How product standardization affects choice: Evidence from the Massachusetts Health Insurance Exchange

This paper examines the effect of choice architecture on Massachusetts' Health Insurance Exchange. A policy change standardized cost-sharing parameters of plans across insurers and altered information presentation. Post-change, consumers chose more generous plans and different brands, but were not more price-sensitive. We use a discrete choice model that allows the policy to affect how attributes are valued to decompose the policy's effects into a valuation effect and a product availability effect. The brand shifts are largely explained by the availability effect and the generosity shift by the valuation effect. A hypothetical choice experiment replicates our results and explores alternative counterfactuals.