About Me
Welcome to my page. I am a PhD candidate at the Department of Economics at Lancaster University. My research interest are in the area of empirical labour economics and health economics with a particular focus on the older workers. My PhD studies older, informal workers' labor supply transition and its relationship with their physical/ mental health status, the availability and generosity of old-age pensions.
Yingying Zhang
PhD Candidate
Phone:
+44 (0)7421886510
Email:
Address:
Department of Economics,
Lancaster University Management School
Lancaster, UK
LA1 4YX
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CV
You can download my CV from here.
Research
Depression, Physical Health, Labour Market Transitions of Older Informal Workers
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The paper studies the sequential causality between labour market transitions and health deterioration, including both mental and physical aspects of health, for older, informal workers in low socio-economic status and lack of age security. We also identify the roles of pure state-dependence, observed socio-economic variables, and unobserved effects in explaining health and labour supply outcomes. Using data from a nation-wide, longitudinal survey in a developing country, we estimate a trivariate, dynamic cross-effects model that allows for the random effects of the three endogenous variables to correlate with each other. We find that depression not only share some unobervables with non-working, most likely to be financial stress, but also increases the probability of non-workers re-entering the labour force, mainly by doing agricultural works, in the subsequent period. Physical health deterioration predicts a higher risk of depression in the subsequent period, larger for men than for women. Depression does not have any effect on men's reported number of physical problems in the subsequent period but increases women's, supporting an asymmetric effect between physical health and mental health. Physical health declines predict an exit from the labour force, more for agricultural workers than non-agricultural workers, men more than women.
The paper provides empirical evidence on the mechanisms behind older, informal workers' labour market transitions by looking into their mental and physical health conditions, and implicates on their long-term health and labor supply outcomes. Adding mental health into the study of health and labour supply transitions can better explain the variation in health effects and the labour supply adjustments after health shocks. Our results also have policy implications that more generous health interventions and modest social pension programs targeting on the older informal workers can have persistent, positive impacts on their health and labour productivity.
Social Pension and Labor Supply Responses of Older Informal Workers
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The paper studies labour supply responses of the rural or informal workers after the introduction of a social pension program. The New Rural Social Pension Scheme in China is both a basic social security program and a contributory retirement pension as the governments replace the role of employers, pay for basic benefits and subsidize individual contributions, while participants, either in or out of the labor force, contribute to their individual accounts. The participation ratio is high, though the contribution levels remain low with the majority of participants paying the minimum requirement levels. The pension program generates a pure income effect for participants reaching the pension-eligible age of 60 when the program started, as they are eligible to receive monthly payment of basic benefits without making any compensatory contributions to the scheme. Studying their labor supply responses provides empirical evidence for a life-cycle, consumption smoothing behaviour of informal workers who are in low-SES, lack of job security and rely mainly on intra-household transfer (mainly from adult children) for old-age support.
Utilizing the different timing of the county-by-county rollout of the pension scheme, we find that male participants start to reduce hours of working by 22.5% when they reach the age of 70, and are 6.2% more likely to retire if they are above 75-year-old. Female participants reduce hours of working by 26.7% if they are aged between 50 and 55 before receiving pension benefits, and by 16.1% when they reach 60. Among the age-ineligible participants, only those contributing at a level higher than the minimum requirement adjust their labour supply after the pension program.
Retirement Effect on Cognitive Functioning and Depression Risk
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Studying mental health is important as mental health problems can affect individual behaviours and cause adverse outcomes such as poor financial decisions and retirement planning. Serious forms of cognitive impairment and depression can cause disability and dementia in old age, and are associated with medical illness such as heart disease and diabetes. The resulting medical and healthcare expenditures generate significant economic costs. The study adds to the limited evidence of retirement effect on cognitive functioning and depression risk based on the context of a developing country where formal retirement ages (50 for the majority female workers and 60 for male workers) are younger than those in U.S., Europe or other developed countries, and where retirement pensions are less generous. Given the long duration of their retirement, how they spend the time, specifically in various social activities and health behaviours, will affect their cognitive ageing process and subjective well-being.
Utilising the different compulsory retirement ages for men and women, blue-collar and white-collar workers in China, the paper examines both the short-run effect of transition into retirement, and the cumulative effect of years in retirement on retirees’ mental and physical health. We estimate dynamic random effects model and use four waves (2011-2018) of data from the China Health and Retirement Longitudinal Study. We find that transition into retirement reduces the risk of depression for both men and women, and improves memory test scores only for men. Years in retirement increases subjective well-being only for women, and do not significantly affect cognitive functioning after accounting for cognitive ageing and effects of other socio-economic factors.
Teaching
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Teaching Assistance, ECON 101 Principles of Economics, 2017--2018, Lancaster University
Teaching Assistance, ECON 403 Microeconometrics, 2018--2021, Lancaster University
Academic Tutors, Maths and Statistics Hub, 2019--2021, Lancaster University