# Measuring Scientific Brain Drain with Hubs and Authorities: a Dual Perspective

## TL;DR

This paper analyzes international scientific migration using a complex network approach, identifying key countries acting as hubs and authorities, and examining their roles and evolution over time from 2000 to 2016.

## Contribution

It introduces a novel dual perspective on scientific migration by applying the HITS algorithm to a temporal, weighted network of country-to-country researcher movements.

## Key findings

- Certain countries act as both hubs and authorities in scientific migration.
- Hubs and authorities share similar local network characteristics.
- Network visualization reveals temporal evolution of key countries' roles.

## Abstract

In this work we study international migrations of researchers, scientists, and academics from a complex-network perspective to identify the central countries involved in the migration phenomenon. We define the scientific migration network (SMN) as temporal directed weighted network where nodes are world countries, links account for the number of scientists moving from one country to another, and timestamps represent years (from 2000 to 2016). 2.8 millions ORCID public profiles are utilized as data source. We then characterize hubs and authorities of the SMN employing the well-know weighted hyperlink-induced topic search (HITS) algorithm to catch the interplay between providing and attracting researchers from a global perspective, and relate these results to other local and global methodologies. We also investigate the local characteristics of successors of hubs and predecessors of authorities to dive deeper into the motivations that establish hubs and authorities as such. Our findings highlight the presence of a set of countries acting both as hubs and authorities, occupying a privileged position in the scientific migration network, and having similar local characteristics. Finally, we showcase how to employ network visualization to evince temporal evolutions of ego-networks of selected hubs and authorities.