Lost letter experiment suggests wealthy London neighbourhoods are ’more altruistic’

’(89/365) One day this will be extinct’ in Sarah G.’s Flickr Stream. (Licensed via Creative Commons.)

Neighbourhood income deprivation has a strong negative effect on altruistic behaviour when measured by a ’lost letter’ experiment, according to new UCL research published today in PLoS One.

Researchers from UCL Anthropology used the lost letter technique to measure altruism across 20 London neighbourhoods by dropping 300 letters on the pavement and recording whether they arrived at their destination. The stamped letters were addressed by hand to a study author’s home address with a gender neutral name, and were dropped face-up and during rain free weekdays.

The results show a strong negative effect of neighbourhood income deprivation on altruistic behaviour, with an average of 87% of letters dropped in the wealthier neighbourhoods being returned compared to only an average 37% return rate in poorer neighbourhoods.

Co-author Jo Holland said: "This is the first large scale study investigating cooperation in an urban environment using the lost letter technique. This technique, g/article/info%3Adoi%

first used in the 1960s by the American social psychologist Stanley Milgram, remains one of the best ways of measuring truly altruistic behaviour, as returning the letter doesn’t benefit that person and actually incurs the small hassle of taking the letter to a post box.

Co-author Professor Ruth Mace added: "Our study attempts to understand how the socio-economic characteristics of a neighbourhood affect the likelihood of people in a neighbourhood acting altruistically towards a stranger. The results show a clear trend, with letters dropped in the poorest neighbourhoods having 91% lower odds of being returned than letters dropped in the wealthiest neighbourhoods. This suggests that those living in poor neighbourhoods are less inclined to behave altruistically toward their neighbours."

As well as measuring the number of letters returned, the researchers also looked at how other neighbourhood characteristics may help to explain the variation in altruistic behaviour - including ethnic composition and population density - but did not find them to be good predictors of lost letter return.