I recently published, together with Olivier Morin, a paper in Cognition and Emotion: Birth of the cool: a two-centuries decline in emotional expression in Anglophone fiction. The main result is about a clear decrease in the emotional tone in English-language literature, starting plausibly from the XIX century, a decrease driven almost entirely by a decline in the proportion of positive emotion-related words, while the frequency of negative emotion-related words shows little if any decline. In other words, English literature became in the last centuries less “emotional” and, in particular, less “positive”.
I gave yesterday a talk, via Skype, in the Cultural Evolution Seminar series at Tartu, Estonia. Oleg Sobchuk and the other organisers are doing a great job, I think, to diffuse knowledge about cultural evolution (and cognitive sciences, and digital humanities, etc.) and I was pleased to give my small contribution. Their website links also to the videos of two of the previous speakers, Cristina Moya and Alex Mesoudi, and provides excellent reading materials and information about cultural evolution.
[The first part is here]
In a successive series of models, published in Scientific Reports, we considered whether other individual-level mechanisms could potentially be mistaken for conformity, generating relations between frequency of a trait and probability to copy it that looked like sigmoids. We choose a few simple and plausible mechanisms (you can refer to the paper for details) and we found that two of them – on a total of seven tested, plus three controls – generated relations for which a sigmoid function produced a better fit than a linear one (see figure below). The codes for running all simulations (written in Matlab) are available through the Open Science Framework.
I recently did some modelling work, in collaboration with Edwin van Leeuwen and others, exploring possible confounds in conformity research. As I discussed in a post some time ago, “conformity”, in cultural evolution, has a precise meaning as a disproportionate tendency to copy the majority. “Disproportionate” here means that the probability to copy a popular cultural trait should be higher than the frequency of the trait itself. In other words, if 60% of your friends wear read, and 40% wear blue, not only you should be more likely to also wear read (this would happen also by copying at random), but your probability to wear read should be higher than 60%. Why is this important? Conformity, in this technical sense, allows majority behaviours to be resistant to random fluctuations, or to changes in population, like migrations, etc. This, in turn, contributes to maintain stable cultural differences between groups.
As a part of my “Cultural Evolution in the Digital Age” exploration (see some previous posts, and here a preprint), I’ve recently read some non-academic books about the topic. This is not intended as a review and clearly not as an exhaustive list, but I decided to make a quick blog post as it may be of some interest. Also, I’d be certainly happy to receive other reading suggestions in the comments.