Research and Teaching

Rain or Shine? Optimal Utility Pricing under Different Weather Patterns

As climate change amplifies more volatile weather patterns, water utilities face increasing difficulty in simultaneously ensuring revenue feasibility, promoting water conservation, and protecting low-income consumers. This paper tests and concludes that price alone cannot achieve these competing policy goals under different weather patterns.

Using granular household data from Austin, TX, and a structural demand model enhanced with satellite imagery-derived vegetation index, I find that because high-water users exist across all income levels, traditional tiered pricing does not work as intended.

When high-demand conditions make conservation measures necessary, low-income families experience an average welfare loss of $74 per month. A program encouraging households to convert 30% of their lawns to water-saving landscapes could generate approximately $72.07 per month in welfare for the lowest-income families, nearly offsetting the financial burden imposed by conservation policies during droughts.

Spatial Heterogeneous Consumers: The Welfare Effect of UberPool

This paper estimates the welfare effect of UberPool as a new product in the ride-hailing market, accounting for heterogeneous preferences within and across locations by using a discrete-type random coefficient nested logit model.

Relative to counterfactual worlds without UberPool, UberPool can increase consumer surplus by 31.58% to 33.51%. Even a partially accessible UberPool by location is 2.57% higher in consumer surplus than a lower-price UberX-only counterfactual, showing the magnitude of the variety effect.

Constrained Price Discrimination on Value of Time

Tolled roads in the US use dynamic pricing mechanisms to react to fluctuating demand, effectively forming price discrimination on value of time. This paper explores price discrimination under two infrastructure constraints: a fixed free price on slow lanes and imperfect substitution between fast and slow lanes due to exit availability.

Following existing research, I developed a structural model for optimal tolls to maximize consumer welfare and conducted counterfactual analysis to study welfare effects of different toll designs and infrastructural investments.

The Welfare and Distributional Effects of Behavior-Based Price Discrimination in Nonlinear Pricing

Urban water utilities traditionally rely on uniform increasing block pricing to balance revenue recovery, resource conservation, and distributional equity. This paper develops and structurally estimates a behavior-based third-degree price discrimination framework.

Using a high-resolution panel of 127,323 single-family households in Austin, Texas, I measure how individual satellite-derived vegetation indices fluctuate in response to temperature and precipitation shocks. Dynamic behavioral segmentation empowers utilities to enforce conservation constraints while achieving progressive distributional equity.

Autumn 2023, 2024

Served as an Assistant Instructor for sections with 100+ undergraduate students on average, with bi-weekly lectures of 75 minutes in the long semester. The course covers interpretation of economic data, statistical models, estimation, basic data analysis in R, and inference in economics.

Quotes from Students

• "Prof. Ji always reviews lectures before each exam which helps us a lot in preparing."
• "The instructor was very approachable and available at all times."
• "He was very good at explaining confusing topics."
• "Mr. Ji always looked willing to help. He was very friendly and helped a lot during office hours."

Sample syllabus: ECO 329, Autumn 2024