I characterize the entire class of consumption rules for finite-horizon models in which consumption is proportional to lifetime wealth. Any such rule can be obtained from a preference model with CRRA period utility. In a steady state with constant interest rates, a proportional consumption rule can be derived from a model with time-consistent preferences or from a model with possibly time-inconsistent preferences in which a household continually reoptimizes future utility discounted relative to the present instant. These two preference models will only coincide for the special case when the discount function is exponential. More generally, there will be two distinct yet observationally equivalent preference models. Hyperbolic-like discounting may arise because that is a simpler way for the brain to process a standard exponential discount function after accounting for mortality risk.

]]>The vintage political business cycle framework of Nordhaus (1975) represents the idea that the macroeconomic business cycle is manipulated opportunistically by an incumbent government to achieve re-election. A key assumption in this prototypical framework is that voters discount their memories about unemployment and inflation at a constant rate. Yet starting with Ebbinghaus (1885) and Jost (1897), a large body of research in psychology documents an empirical regularity that has come to be known as Jost's Second Law of Forgetting-individuals discount recent memories at a higher rate compared to the rate at which they discount older memories. I find that incorporating this insight from psychology (i.e., hyperbolic memory discounting) into the benchmark framework moderates the amplitude of the predicted political business cycle. © 2015 Elsevier B.V.

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