Longitude

When the OED was compiled, more than a hundred years ago now, longitude was all about length, and by extension about lines of longitude. Lines which are calculated, in a relic of our mercantile & imperial past, from a point quite near Epsom, with the longitude of this part of Epsom being about a quarter of a degree west of the meridian – and with it taking 360 such degrees to get right around the world.

But things move on, and when I was starting out in the world of work, in the world of population and vital statistics, then called the Office of Population, Censuses and Surveys, statisticians were distinguishing cross sectional analyses at a point in time from longitudinal studies which drew on data about individuals collected over time, possibly a long period of time. A  not very good – but bridging – analogy would be the very different information one gets about long animals like worms and snakes from cross sections than one gets from longitudinal sections.

At the time of that start, something called the Longitudinal Study had just been invented, a study which involved keeping track of a lot of people over a long period of time – more or less for ever. Putting long animals aside, part of the justification was a desire to improve the analysis of mortality, to do better than the information available at death. Occupation recorded at death, for example, is not always a good description of occupation during life. Another part was a desire to improve the analysis of fertility, for example, to bring to bear information about birth spacing. With fertility being an important input to population projections and with these last being an important input to planning for the future.

At the time, an important statistical event; a 1% sample of the population of England and Wales, roughly half a million people, which started with the 1971 Census and which has carried on ever since, that is to say for getting on for fifty years now. The study links together the records from successive censuses with those arising from vital events, things like getting married, having children or getting cancer. A high quality study, described at, for example, references 2 and 3. And there are other longitudinal studies run by the ONS, for example one associated with the long running Labour Force Survey.

These two studies are large and comprehensive – but also, I imagine, very competitive. You have to work very hard to get your pet subject added to one of these long running, general purpose studies and I dare say there are learned committees which rule on such matters. You may well do better to do your own study: it might be small but it would be your own. Against that, there is the considerable expense and difficulty of keeping in touch with hundreds of people over the years. And then there is the need for quick results, for quick publication to impress the people who award grants and jobs. People who have to be impressed these days if you want to stay in business.

Then just a few days ago I commented at reference 1 on the lack of longitudinal studies of the shapes of heads.

So I was pleased yesterday to be pointed at a substantial longitudinal study of primary school children at maintained schools in Surrey, mined to produce the paper at reference 4. The burden of which appears to be that children who have language problems at the age of 5 – and it seems that getting on for 10% of children do – are more likely to have difficulty recognising emotions in others from visual and vocal cues at the age of 11 – key social skills for the growing child. Not being able to read (as it were) cues of this sort is bad news.

I did wonder how keen the teachers were who had to fill out all the forms for the selected children. Just another office chore, taking away from the time and energy available for the real work of teaching?

But interesting to me because the paper suggests there is interaction between describing emotions in words and feeling emotions. Perhaps it is important for us to be able to carve emotion into word-labelled chunks which suit the world in which we are living. A skill which, like that of learning to utter and understand the small chunks of sound (phonemes) which underpin our language, is best learned young. There was talk of a relatively new theory about human emotion called the theory of constructed emotion, otherwise TCE, formerly the conceptual act theory, and a reference to a recent paper about conceptual synchrony by Gendron & Feldman – a paper which I shall now get stuck into.

I think the general idea is that an emotion is a construct in rather the same way of, for example, an image of a bird on the lawn. A construct which is a mixture of, a balance between bottom-up stimulation and top-down knowledge. An output rather than an input. We shall see!

PS: the picture of a blackbird on the lawn was turned up by Google. Taken by Kasper Nymann of Denmark. Supplied by Picfair. Slightly degraded for reasons of copyright.

References

Reference 1: https://psmv4.blogspot.com/2020/06/head-growth.html. 

Reference 2: https://www.ons.gov.uk/aboutus/whatwedo/paidservices/longitudinalstudyls.

Reference 3: Longitudinal Study 1971-1991: History, organisation and quality of data - Lin Hattersley, Rosemary Creeser – 1995. Available from reference 2.

Reference 4: Early language competence, but not general cognitive ability, predicts children's recognition of emotion from facial and vocal cues – Sarah Griffiths, Shaun Kok Yew Goh, Courtenay Fraiser Norbury and others – 2020.

Reference 5: Emotion Perception as Conceptual Synchrony - Maria Gendron, Lisa Feldman Barrett – 2018.