‘Who Tweets’ is an interesting piece of recent research which attempts to determine some basic demographic characteristics of Twitter users, relying on nothing but the data provided by the users themselves in their twitter profiles.
Based on a sample of 1470 twitter profiles* in which users clearly stated** their age, the authors of ‘Who Tweets’ found that 93.9% of twitter users were under the age of 35. The full age-profile of twitter users (according to the ‘Who Tweets’/ COSMOS data) compared to the actual age profile taken from the UK Census is below:
Compare this to the Ipsos MORI Tech Tracker report for the third quarter of 2014 (which the above research draws on) which used face to face interviews based on a quota sample of 1000 people.
Clearly this shows that only 67% of media users are under the age of 35, quite a discrepancy with the user-defined data!
The researchers note that:
‘We might… hypothesis that young people are more likely to profess their age in their profile data and that this would lead to an overestimation of the ‘youthfulness’ of the UK Twitter population. As this is a new and developing field we have no evidence to support this claim, but the following discussion and estimations should be treated cautiously.
Looking again at the results from the Technology Tracker study conducted by Ipsos MORI, nearly two thirds of Twitter users were under 35 years of age in Q3 of 2014 whereas our study clearly identifies 93.9% as being 35 or younger. There are two possible reasons for this. The first is that the older population is less likely to state their age on Twitter. The second is that the age distribution in the survey data is a function of sample bias (i.e. participants over the age of 35 in the survey were particularly tech-savvy). This discrepancy between elicited (traditional) and naturally occurring (new) forms of social data warrants further investigation…’
This comparison clearly shows how we get some very different data on a very basic question (‘what is the age distribution of twitter users’?) depending on the methods we use, but which is more valid? The Ipsos face to face poll is done every quarter, and it persistently yields results which are nothing like COSMOS, and it’s unlikely that you’re going to get a persistent ‘tech savy’ selection bias in every sample of over 35 year olds, so does that mean it’s a more accurate reflection of the age profile of Twitter users?
Interestingly the Ipsos data shows a definite drift to older users over time, it’d be interesting to know if more recent COSMOS data reflects this. More interestingly, the whole point of COSMOS is to provided us with more up to date, ‘live’ information – so where is it?!? Sort of ironic that the latest public reporting is already 12 months behind good old Ipsos –
At the end of the day, I’m not going to be too harsh about the above ‘Who Tweets’ study, it is experimental, and many of the above projects are looking at the methodological limitations of this data. It would just be nice if they, err, got on with it a bit… come on Sociology, catch up!
One thing I am reasonably certain about is that the above comparison certainly shows the continued importance of terrestrial methods if we want demographic data.
Of course, one simple way of checking the accuracy of the COSMOS data is simply to do a face to face survey and ask people what there age is and whether they state this in their Twitter profiles, then again I’m sure they’ve thought of that… maybe in 2018 we’ll get a report?
*drawn from the Collaborative Online Social Media Observatory (COSMOS)
**there’s an interesting discussion of the rules applied to determine this in the ‘Who Tweets’ article.