In this paper, we develop a revealed preference methodology that allows us to explore whether time inconsistencies in household choice are the product of individual preference nonstationarities or the result of individual heterogeneity and renegotiation within the collective unit. An empirical...

This paper develops a revealed preference methodology for exploring whether time inconsistencies in household choice are the product of nonstationarities at the individual level or the result of individual heterogeneity and renegotiation within the collective unit. An empirical application to...

We study collective decisions by time-discounting individuals choosing a common consumption stream. We show that with any heterogeneity in time preferences, utilitarian aggregation necessitates a present bias. In lab experiments three quarters of `social planners' exhibited present biases, and...

Hyperbolic discounting with naiveté is widely believed to provide a better explanation than exponential discounting of why people borrow so much and why they wait so long to save for retirement. We reach a different set of conclusions. We show that if financial planning is enriched to include...

Dybvig [1995] finds optimal spending and investment strategies for a perpetual endowment that has no tolerance for spending declines. His spending rule is a ratchet --- spending never decreases, but has a substantial chance of increasing. We find the ratchet consumption rule for an investor with...