Science1 publisher2 min readPublished
Sydney and Melbourne researchers put a dollar value on eudaimonic well-being for transport and urban project appraisals
Sydney and Melbourne researchers price a one-point gain in eudaimonic well-being, a measure of purpose and connection, at about A$273 in 2008 dollars. Counting it in appraisals of bike paths and parks first needs evidence on how far a project moves those scores.
The Scientist · Science desk
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What happened
- Transport and urban project appraisals have so far assigned a dollar value only to life satisfaction, leaving longer-term purpose and connection unpriced.
- Dollar values for changes in life satisfaction have been used in cost-benefit analyses in Australia and, more commonly, in the United Kingdom.
- Modeled together, both values fell somewhat because the two concepts overlap, but the eudaimonic value remained substantially larger.
Compiled by The ScientistSomething wrong?How this is made
Why it matters
- constraint Until a study measures how many points of purpose a given path or park adds, and for how many residents, the per-point price cannot be turned into a project benefit.
- decision Agencies that already price life satisfaction would have to use overlap-adjusted values, since adding both separate figures to one project would count shared benefits twice.
- capability Schemes such as 20-minute neighbourhoods, currently argued on car use and emissions, would gain a way to state social connection in dollars beside travel-time savings.
The dollar value is a ratio between two statistical associations. In the data analysed by the University of Sydney and University of Melbourne team, higher income went with a lower risk of social exclusion, and so did higher well-being [c15, c5]. Making more trips, having strong social networks and feeling connected to one's community lowered that risk as well [4]. Comparing the income effect with each well-being effect let the team infer how many dollars match one point of change on each scale [5]. In 2023 prices, the eudaimonic point comes to about A$387 [8].
The "nearly three times" comparison with life satisfaction is made point for point, and the points are not the same size [9]. Ryff's Psychological Well-Being Scale, whose six dimensions include purpose in life and positive relations with others, is scored from 0 to 6 [6]. The Personal Well-being Index, which covers seven life domains, is scored from 0 to 10 [7]. "Because the two scales have different ranges, a one-unit increase in eudaimonic well-being will be harder to achieve than a one-unit increase in life satisfaction," the researchers wrote [10].
Valued across each full scale, eudaimonic well-being comes to A$1,638 (273 times 6) and life satisfaction to A$930 (93 times 10), a ratio of about 1.8 [d1, d2]. That calculation treats every point as worth the same anywhere on its scale. It also assumes the A$93 is in 2008 prices. The stated ratio supports that reading: 273 over 93 is 2.9, while 387 over 93 would be 4.2 [16].
The thing this doesn't tell you is whether building anything changes the scores. The valuation rests on how well-being and income each track exclusion risk once other influences are controlled for [c5, c9]. That yields an income equivalent for a point of well-being. It does not show that a new park or bike path raises anyone's sense of purpose, and the researchers' account reports no measured effect of a project on either scale [5].
I think the study gives appraisers a usable income equivalent for purpose and connection, and that the per-point ratio overstates its lead over life satisfaction [15]. Whether bike paths and parks are undervalued turns on effect sizes from real projects. The researchers wrote that the missing well-being calculation "could be worth even more than what we're currently measuring" [17].
What to watch
- A study measuring how far a specific bike path, street redesign or park shifts residents' Ryff scores, supplying the quantity the per-point value needs.
- Whether Australian or UK appraisal guidance, which already uses life-satisfaction values, adopts a eudaimonic value and uses the overlap-adjusted joint-model figures.
- Publication of the joint-model values, which the researchers say fell somewhat when both well-being measures were modeled together.