Epidemic oscillations induced by social network control: the discontinuous case

Since the early days of control theory,  engineers have understood that feedback can give rise to spontaneous and sustained oscillations. Examples abound in engineering systems such as thermostats and steering devices, as well as in natural and biological systems – for example, in homeostasis or diabetes in the human metabolism. Feedback-induced oscillations have also affected recent governmental efforts to control the covid-19 pandemic crisis through measures such as social distancing, lock downs and quarantine. Read more

The Long Run Evolution of Absolute Intergenerational Mobility

In the mid-20th century, many developed economies experienced several generations of high prosperity, with children generally earning higher incomes than their parents had at the same age. In economics, this is technically known as increasing absolute intergenerational mobility. For the United States, however, studies suggest that such mobility has more recently been falling. It decreased from 90% for children born in 1940 to just 50% for those born in 1980, mostly due to changes in the income distribution, but also due to slower economic growth. Whether this pattern also holds for other countries and birth cohorts is less clear. Read more

Choice history effects in mice and humans improve reward harvesting efficiency

In foraging for food and other resources, animals have to make repeated choices about where best to search. Experimental studies of such decisions typically work with the simplifying assumption that animals’ past decisions should have no impact on the distribution of actual resources, which remains fixed. Many such studies have nevertheless found that animals’ current decisions do often depend on their past decisions, and interpret this as a bias Read more