Recent Publications

Little attention is given to the role of migration in global population projection models. Most demographers set future levels of net migration on trajectories towards zero in all countries, nullifying the impact of migration on long-run projected populations. Yet as fertility and mortality rates fall, the role of migration on future population change is becoming more pronounced. In this paper we develop future long-run migration scenarios to provide a range of possible outcomes. Our alternative migration scenarios are linked to the Shared Socioeconomic Pathways (SSP), widely used in research on global environmental change. These are utilized as inputs for a global cohort component projection model to obtain population totals up until 2100 for all countries. The results illustrate the important role of migration assumptions in long run projections, especially in post demographic transition countries. Further, they provide plausible alternatives to projections based on the commonly used, but poorly justified, convergence to the zero net migration assumption
In Demographic Research, 38 (54) 1635–1662.,2018

Within one generation, the South Korean economy developed from one of the poorest countries in the world during the 1950s to a developed, high-income country by the end of the 1990s. During the latter part of this period, South Korea (hereafter called Korea) experienced rapid demographic change characterized by a steep decline in fertility levels and abnormally high sex ratios at birth. Unlike other East and South-East Asian countries that underwent similar economic and demographic changes, Korea has witnessed a steady decline in the sex ratios at birth since the end of 1990s through 2000s. In this paper, we visualize the current spatial distribution of population born during the peak years of sex ratios at birth.
In Environment and Planning A: Economy and Space, 50 (5), 941-944.,2018

In comparison with other developed nations, there is a relative lack of analyses on internal migration flow in South Korea. During the last 50 years, the country has witnessed distinct changes in both the levels and patterns of internal migration. Traditionally, the faster developing north-west administrative units (Seoul, Incheon and Gyeonggi regions) have accounted for the majority of in-migration. However, since 2011, internal migration in Korea has become more diffuse, with migrants moving to a greater variety of regions. We visualize these changes using chord diagram plots.
In Regional Studies, Regional Science, 5(1).,2018

An indirect estimation method is used to derive country to country migration flows from changes in global bilateral stock data. Estimates are obtained over five- and 10-year periods between 1960 and 2015 by gender, providing a comprehensive picture of past migration patterns. The estimated total of global international migrant flows generally increases over the 55-year time frame. The global rate of migration over five- and 10-year periods fluctuate at around 0.65 and 1.25 percent of the population, respectively. The sensitivity of estimates to alternative input stock and demographic data are explored.
In International Migration Review, 52 (3), 809-852.,2017

We adapted the chord diagram plot to visualize China’s recent inter-provincial migration during 2010–2015. The arrowheads were added to present the direction of the flows. This method allows us to show the complete migration flows between 31 provinces in China including the direction and volume of the flows. The spatial component was also clearly depicted in the plot using four color palates representing four regions in China (i.e. East, Center, West, Northeast) and arranging the 31 provinces in an approximate geographic order. Besides that, we extend the chord diagram plot to describe China’s bilateral net migration during 2010–2015.
In Environment and Planning A, 49(11).,2017

The relationship between climate change and human migration is not homogenous and depends critically on the differential vulnerability of population and places. If places and populations are not vulnerable, or susceptible, to climate change, then the climate-migration relationship may not materialize. The key to understanding and, from a policy perspective, planning for whether and how climate change will impact future migration patterns is therefore knowledge of the link between climate vulnerability and migration. However, beyond specific case studies, little is known about this association in global perspective. We therefore provide a descriptive, country-level portrait of this relationship. We show that the negative association between climate vulnerability and international migration holds only for countries least vulnerable to climate change, which suggests the potential for trapped populations in more vulnerable countries. However, when analyzed separately by life supporting sector (food, water, health, ecosystem services, human habitat, and infrastructure) and vulnerability dimension (exposure, sensitivity, and adaptive capacity), we detect evidence of a relationship among more, but not the most, vulnerable countries. The bilateral (i.e., country-to-country) migration show that, on average, people move from countries of higher vulnerability to lower vulnerability, reducing global risk by 15%. This finding is consistent with the idea that migration is a climate adaptation strategy. Still, ~6% of bilateral migration is maladaptive with respect to climate change, with some movement toward countries with greater climate change vulnerability.
In Sustainability, 9(5), 720,2017

Recent Posts

During the last few months I have given some introductory talks on international migration in Asia and Europe. I had a couple of requests to share the animated chord diagrams that I created for others to use in their teaching materials. These are below, along with some extra plots for Africa and the Americas (Northern, Central and Southern America as well as the Caribbean.) The chords in the diagrams represent the connection between the places of birth (at the base of the chord) and places of residence (at the arrow head of the chord).


Background I’m loving the magick package at the moment. Reading through the vignette I spotted the image_morph() function. In this post I experiment with the function to build the GIF below that shows the changes in the England football first kit over time, using images from the excellent Historical Football Kits website. Scraping The Historical Football Kits website has a detailed section on England kits spread over six pages, starting from the first outfits used in 1872.


Background A little while ago my paper in International Migration Review on global migration flow estimates came out online. The paper includes a number of directional chord diagrams to visualize the estimates. Recently I have been playing around tweenr and the magick packages for animated population pyramids. In this post I attempt to show how to use these packages to produce animated directional chord diagrams of global migration flow estimates


Recent & Upcoming Talks

European International Migration Patterns
13 July 2018 2:00 PM
Driving Factors of Asian International Migration Flows
13 July 2018 11:15 AM
Probabilistic Method for Combining Internal Migration Data
07 June 2018 9:20 AM
Probabilistic Method for Combining Internal Migration Data
04 May 2018 12:30 PM
Visualizing Migration Flows: How to Design and Produce Animated Directional Chord Diagrams in R
01 May 2018 12:00 PM
Driving Factors of Asian International Migration Flows
26 April 2018 8:30 AM
Gender, Education and Marital Status Differentials in Migration
22 February 2018 12:00 PM
Gender, Education and Marital Status Differentials in Migration
09 February 2018 3:00 PM


ARDI International Migration Pillar

Exploring international migration patterns for the Globe, Asia and Shanghai.

Combining Migration Data

Combining traditional and emerging big data sources to model population. Funded by Der Jubiläumsfonds der Stadt Wien für die Österreichische Akademie der Wissenschaften.

Global Migration Predictions

The Prediction of Future Migration Patterns for Improved Global Population Projections. Funded by National Science Foundation of China Research Fund for International Young Scientists.


Currently Teaching at Shanghai University:

  • 3XS371026 Data Science for Demography, Semester 1, 2018-19
  • 3XS371022 Statistical Methods for Demography, Semester 2, 2018-19


  • +86 021 6613 3271
  • Office 543, School of Sociology and Political Science, Shanghai University, 99 Shangda Road, Baoshan District, Shanghai. 上海市宝山区上大路99号上海大学东区社会学院大楼543
  • Office Hours by Appointment