I performed a very cursory literature review on the subject. Overall it seems the psychology research suggests that older people discount the future less than younger people, which might suggest giving their votes more weight.
Usually such a brief perusal of the literature would not give me a huge amount of confidence in the core claims; however in this case the conclusion should seem prima facie very plausible to anyone who has ever met a young boy.
In no particular order:
Age Differences in Temporal Discounting: The Role of Dispositional Affect and Anticipated Emotions:
Advanced age was associated with a lower tendency to discount the future, but this effect reached statistical significance only for the discounting of delayed gains.
Age-Related Changes in Decision Making:
Older adults are not always risk-averse, and their ability to postpone gratification tends to exceed that of younger adults.
Aging and altruism in intertemporal choice:
Research on life span changes in motivation suggests that altruistic motives become stronger with age, but no prior research has examined how altruism affects tolerance for temporal delays. Experiment 1 used a realistic financial decision making task involving choices for gains, losses, and donations. Each decision required an intertemporal choice between a smaller-immediate and a larger-later option. Participants more often chose the larger-later option in the context of donations than in the context of losses; thus, parting with more of their overall capital when the act of doing so benefited a charity. As predicted, the magnitude of this “altruism effect” was amplified in older relative to younger adults. -
Following Advice Because it’s Been Paid For: Age, the Sunk-Cost Fallacy, and Loss Aversion:
[Y]ounger adults commit the sunk-cost fallacy more frequently, and make normatively correct decisions less frequently,than older adults when hypothetical sunk costs are at stake … Younger adults made fewer initial investments of money on the Calorie Estimation Task than older adults. Younger adults demonstrated the sunk-cost fallacy more frequently, overinvested more after demonstrating the fallacy, and made the normatively correct decision less frequently than older adults on the hypothetical self-report measure of the sunk-cost fallacy. Younger adults indicated that they were more averse to hypothetical monetary losses on a Tradeoff Loss Aversion Task and more averse to hypothetical monetary losses on a Delay Discounting Loss Aversion Task. … Older adults did not demonstrate the sunk-cost fallacy on the Calorie Estimation Task by following more expensive advice more closely than less expensive advice. -
Decision Making in Older Adults: A Comparison of Delay and Probability Discounting Across Ages:
[O]lder adults discounted delayed rewards less steeply than young adult
Acute stress and altruism in younger and older adults:
Even under acute psychosocial stress, older adults make more altruistic choices than younger adults.
Age-related differences in discounting future gains and losses:
Results indicated that impaired older adults discounted the future more than unimpaired older adults. Interestingly, middle-aged adults discounted future gains at a similar rate as impaired older adults, but discounted future losses less than impaired older adults (and similarly to unimpaired older adults).
Age‐related differences in delay discounting: Immediate reward, reward magnitude, and social influence:
Younger adults exhibited higher levels of delay discounting than older adults.
The only evidence I’ve found that older people might discount more was a Chinese study. I’m not sure why Chinese people would be different in this regard, though obviously their culture is different in many ways—or, the paper might just be wrong.
Age differences in delay discounting in Chinese adults:
The current study aimed to clarify this relationship using a relatively large sample of Chinese adults with a wide age range (viz., 18 to 86 years old). A total of1288 individuals completed the Monetary Choice Questionnaire. Results showed that the rate of delay discounting increased with age across adulthood, with younger participants (18–30 years) discounting lessthan both middle-aged participants (31–60 years) and older participants (over 60 years); and middle-aged participants discounting less than older participants. Furthermore, when the reward magnitude was large, participants were more likely to wait for delayed rewards.
This paper has increased my general skepticism on the accuracy of any estimates of discount rates: Time Discounting and Time Preference: A Critical Review. It has a table listing studies that find discount rates ranging from −6% to ∞% .
Hi, thanks so much for doing this! This is really interesting.
Something I think wasn’t sufficiently clear from the post itself: even using the the weighting scheme I suggested in the post, that would move the median voter (in the US) from age 55 to age 40. (H/T Zach Groff for these numbers. Note this doesn’t account for incentive effects, of younger people being more likely to go out to vote, which could lower the median age to a little under 40.) And under reasonable assumptions (with the most controversial being single-peaked preferences), the median voter is decisive. So it’s not like 20 year olds are now deciding what happens. On the epistocratic question, then, we should be asking whether we think 40yr olds will make better decisions than 55 year olds; not whether 20 year olds make better decisions than 60 year olds. I’d need to dig into the studies a lot more to determine whether 40 year olds discount more steeply than 55 year olds.
And then, I’ve only done a quick scan of the studies you link to, but I don’t think the discounting literature you’re pointing to is actually all that relevant, because the timescales they are looking at are so short: 90 days in one case; up to 6 months in another. Whereas the time horizons for the impact of political decisions, especially the most important ones, are on the order of years or decades—over such timescales, discounting due to risk of death become a much bigger factor than discounting due to impulsiveness / impatience.
Again, I think this depends on what timescales we’re talking about. Sure, it seems prima facie plausible that someone who is 21 is more likely to prefer $5 today to $10 in a month’s time than a 60 year old is. But (on the assumption of self-interest) I’d strongly wager that a 21 year old is more likely to prefer $100 in 40 years’ time over $10 in a month’s time than a 60 year old is, because the 21 year old is so much more likely to be around and be able to enjoy the benefits.
The altruism and age discussion is interesting, and I agree that if it were borne out it could form part of an epistocratic argument for the age-weighting going the other way around.
the the weighting scheme I suggested in the post, that would move the median voter (in the US) from age 55 to age 40. (H/T Zach Groff for these numbers. Note this doesn’t account for incentive effects, of younger people being more likely to go out to vote, which could lower the median age to a little under 40.) And under reasonable assumptions (with the most controversial being single-peaked preferences), the median voter is decisive. So it’s not like 20 year olds are now deciding what happens. On the epistocratic question, then, we should be asking whether we think 40yr olds will make better decisions than 55 year olds; not whether 20 year olds make better decisions than 60 year olds. I’d need to dig into the studies a lot more to determine whether 40 year olds discount more steeply than 55 year olds.
If you want to give extra influence to 40 year olds, it probably makes more sense just to give 40 year olds more votes. Otherwise you’re putting a lot of faith in one model of how voters work, despite the median voter theorem having lost some of its academic appeal over time (multidimensional preferences, selectorate vs electorate, veto players, heresthetics).
Additionally, if we did give young people lots of extra votes, we’d probably get a Goodheart’s Law type situation, where politicians would adopt special policies designed to exploit it—like promising student debt forgiveness, or to ban tuition fees (the latter of which seemed to have been quite successful at manipulating UK students to vote for the Democrat Party in 2015!)