Frontiers: Smoke and Mirrors: Impact of E-cigarette Taxes on Underage Social Media Posting

E-cigarette use, or vaping, is a public health concern, with particular worries about underage use. The U.S. government is expected to introduce federal taxation on vaping. The potential deterrent effect of such a tax on underage users is understudied because of the absence of underage use data. To cut through this data fog, we use Instagram images from 2016 to 2018 to estimate whether a tax change in California affected vaping-related posting by underage users. This posting behavior is a potential proxy for consumption behavior. We use image analysis (residual neural networks) and latent factor models for causal inference of tax effects. Compared with counterfactuals, we find a relative decline in the incidence of underage users (in effect a slower increase in postings) in vaping-related images in California for about six months, with no effects after. There is gender and race heterogeneity in these effects. Our proposed approach of using near real-time social media images can be helpful to regulators and managers, especially in the rapidly changing landscape expected in the coming months.