[1] Kong, Nancy, Lars Osberg, and Weina Zhou. "The shattered “Iron Rice Bowl”: Intergenerational effects of Chinese State-Owned Enterprise reform." Journal of Health Economics 67 (102220).
Abstract: Reform of the Chinese State-Owned Enterprise (SOE) sector in the late 1990s triggered massive layoffs (34 million employees) and marked the end of the “Iron Rice Bowl” guarantee of employment security for the remaining 67 million workers. An expanding international literature has documented the adverse health impacts of economic insecurity on adults, but has typically neglected children. This paper uses the natural experiment of SOE reform to explore the causal relationship between increased parental economic insecurity and children’s BMI Z-score. Using province year-level layoff rates and income loss from the layoffs, we estimate a generalised difference-in-differences model with individual fixed effects and year fixed effects. For a medium-build 10-year-old boy, a median treatment effect implies a gain of 1.8 kg and a 2.2-percentage-point increase in the overweight rate due to the reform. The weight gain for boys whose SOE parents kept their jobs indicates the importance of anxiety about potential losses, as well as the experience of actual loss. Unconditional quantile regressions suggest that boys who are heavier are more likely to gain weight. Girls are not significantly affected. Intergenerational effects therefore increase the estimated public health costs of greater economic insecurity.
[2] Kong, Nancy and Weina Zhou. (2021). "The curse of modernization? Western fast food and Chinese children's weight." Health Economics, 30(10) 2345-2366. (Working paper version)
Abstract: The income-adjusted price of fast food in China is five times more than in the US, yet we show that the introduction of Western fast-food restaurants to China still leads to significant weight gain in children. Using the community-year-level presence of Western fast-food outlets, difference-in-differences estimations find a 4.8-percentage-point increase in the prevalence of overweight/obese children after controlling for child and year fixed effects. The effect decreases at a distance of 3 to 4 km from a fast-food restaurant, and we find no further weight gain 2 years after the restaurant's introduction. The underweight rate is not affected by fast food introduction. The increase in fat share of energy intake serves as the channel for weight gain. Children in high-income families, younger than 11 years, and girls are more affected than other Chinese children.
[3] Kong, Nancy, Shelley Phipps, and Barry Watson. "Parental economic insecurity and child health." Economics and Human Biology 43(101068). (Working paper version)
Media coverage: The Conversation, The Guardian
Abstract: We explore the effects of parental economic insecurity on their children’s hyperactivity and anxiety. Our central argument is that even after controlling for current family income and employment status, parents may have legitimate feelings of economic insecurity, and these may be detrimental for their children. Data from the National Longitudinal Survey of Children and Youth indicate that the health of 2- to 5-year-old children is worse when parents report themselves to be “worried about having enough money to support the family.” In particular, boys are more hyperactive and girls are more anxious when parents feel less economically secure. Changes in parenting styles appear to be channels through which parental economic insecurity affects their children.
[4] Kong, N., Dulleck, U., Jaffe, A. B., Sun, S., & Vajjala, S. (2023). Linguistic metrics for patent disclosure: Evidence from university versus corporate patents. Research Policy, 52(2), 104670. (Working paper version NBER Working Paper No. 27803)
Media coverage: The New York Times
Abstract: Encouraging inventors to disclose new inventions is an important economic justification for the patent system, yet the technical information contained in patent applications is often inadequate and unclear. This paper proposes a novel approach to measure disclosure in patent applications using algorithms from computational linguistics. Borrowing methods from the literature on second language acquisition, we analyze core linguistic features of 40,949 U.S. applications in three patent categories related to nanotechnology, batteries, and electricity from 2000 to 2019. Relying on the expectation that universities have more incentives to disclose their inventions than corporations for either incentive reasons or for different source documents that patent attorneys can draw on, we confirm the relevance and usefulness of the linguistic measures by showing that university patents are more readable. Combining the multiple measures using principal component analysis, we find that the gap in disclosure is 0.4 SD, with a wider gap between top applicants. Our results do not change after accounting for the heterogeneity of inventions by controlling for cited-patent fixed effects. We also explore whether one pathway by which corporate patents become less readable is use of multiple examples to mask the “best mode” of inventions. By confirming that computational linguistic measures are useful indicators of readability of patents, we suggest that the disclosure function of patents can be explored empirically in a way that has not previously been feasible.
[5] Cobb-Clark, Deborah, Nancy Kong, and Hannah Schildberg-Hörisch "The stability of self-control in a population-representative study" Journal of Economic Psychology 102599. (Working paper version IZA DP No. 14976)
We investigate the stability of self-control at the population level. Analyzing repeated Brief Self-Control Scale scores, we demonstrate that self-control exhibits a high degree of mean-level, rank-order, and individual-level stability over the medium term. Changes in self-control are not associated with major life events, nor are they economically important. The stability of self-control is particularly striking given our study period (2017-2020) spans the onset of the COVID-19 pandemic.
[6] Kong, Nancy, Jack Lam "Physical isolation and loneliness: Evidence from COVID lockdowns in Australia." (2024) Journal of Economic Behavior & Organization, 224, 598-623.
Media coverage: ABC news, ABC Radio, The Conversation, UTS News
Loneliness contributes to mortality risk, comparable to the risks associated with smoking and obesity, although the causal determinants of loneliness remain less clear. This paper leverages mandatory stay-at-home orders in Australia as a natural experiment and employs data from a panel study to investigate the causal link between physical isolation and loneliness. By employing variations in the number of lockdown days experienced by respondents up until their interview dates, and utilizing difference in-differences analyses with individual, region, and year fixed-effects estimations, we find, contrary to expectations, that the number of days in lockdown does not significantly impact loneliness. Our study examines cumulative, concurrent, and nonlinear effects, and assesses external validity through community morale and peer effects during lockdowns using spatial analysis. Additionally, we delve into heterogeneous effects across various factors, such as income, age, personality, living arrangements, and remoteness, finding statistically and empirically insignificant effects. However, for extroverts and young people, we observe weak statistical significance. We investigate exclusion restrictions by analyzing factors including social contacts, internet access, job industry, and household characteristics in relation to loneliness; as well as time use and relationship satisfaction to better understand the underlying mechanism. Our study challenges the notion that 'being alone' and 'being lonely' are interchangeable concepts, providing the first empirical causal evidence of no links between the two. Furthermore, our findings refine earlier understandings of social isolation, highlighting that it likely encompasses factors beyond physical isolation.
[7] Watson, B., Kong, N., Phipps, S., & Daley, A. (2025). Dreaming of a Brighter Future? The Impact of Economic Circumstances on University Aspirations. Social Indicators Research, 180(1), 383-410.
We investigate how economic circumstances (measured in terms of poverty and economic insecurity) impact the educational aspirations of youth, age 12-15. Using the Canadian National Longitudinal Survey of Children and Youth, we find that poverty is associated with reduced university aspirations from the perspective of the youth (9 percentage points) and their mother (12-13 percentage points). Further, poverty incidence matters more than depth. Interestingly, economic insecurity is not associated with educational aspirations, and this result persists regardless of how we measure insecurity. This may be due to the fact that, over time, poverty is more likely to persist than economic insecurity. Consequently, while the latter may be seen as a temporary shock, the former may create a feeling of hopelessness, thereby reducing aspirations. Controls for academic effort, including standardised test scores, daily reading, and getting good grades do not impact these findings. Results therefore suggest that alleviating child poverty may improve educational aspirations at a critical time in a youth’s life.
[8] Kong, N., Rowell, D., & Zweifel, P "Understanding Sick Leave: The Interplay between Health and Economic Incentives." Applied Economics. (Accepted)
Sick leave has important implications for worker well-being, productivity, and public health. This study develops a behavioural framework in which workers exert effort to obtain medical certification, linking economic incentives to observed sick leave behaviour. The model formalises how unobserved search effort affects the probability of obtaining certified leave and generates testable predictions on the roles of health, wages, job security, and labour market conditions. Using nationally representative panel data from the Household, Income and Labour Dynamics in Australia (HILDA) Survey, we estimate pooled cross-sectional, individual fixed effects, and Hausman–Taylor models to account for unobserved heterogeneity and potential endogeneity. The results indicate that poor health and permanent employment are associated with higher levels of sick leave, while higher unemployment risk is associated with reduced leave-taking. Wage effects appear to operate through interactions, with higher wages linked to greater sick leave among workers in unfavourable health and those in more secure employment. Gender differences are consistently observed, with men taking fewer sick leave days than women, while unemployment benefits show no statistically significant association. The findings suggest that sick leave reflects both health needs and economic incentives, highlighting the importance of policies that enable appropriate leave-taking without penalising vulnerable workers.
Working papers:
Gender Bias Within Chinese Families—Who Eats First in Tough Times? (with Lars Osberg)
Abstract: This paper investigates within family the effects of parental income shocks on individual’s dietary intake. Drawing on large-scale panel data from the China Health and Nutrition Survey from 1991 to 2011, I examine the macronutrient intakes of 2 to 17-year-old siblings of mixed-sex and their parents in 3,244 families. Gender disparity in carbohydrate intakes accounts for 15 percentage points in child sample, 30 percentage points in adolescents, and 50 percentage points between parents using the Dietary Reference Intakes standards. The paper further shows that when families experience negative income shocks, food is allocated in the order of fathers, sons, daughters and mothers. Gender inequality of intra-household resource allocation is heightened in the event of large income losses.
The Impact of Healthcare Access on Health Inequality: Evidence from Spatial Analysis (MN Nejad, S. Yu, M. Hajizadeh)
Health status inequality and healthcare access inequity have typically been studied independently. This paper bridges these two areas by investigating the impact of healthcare access and equity on health inequality. Using a nationally representative dataset of individuals in Australia, we measure the extent of health and healthcare utilization inequality across different dimensions and track their changes over the last 20 years. We integrate spatial analysis by linking a complete list of hospital locations to individual residences at the postcode level, using the distance to hospitals as a proxy for healthcare access. Our findings reveal that Australia exhibits slight pro-poor healthcare utilization but minimal inequality in health status based on income or proximity to hospitals. After controlling for individual confounders, we demonstrate that people living closer to hospitals have better health outcomes but do not significantly differ in healthcare utilization compared to those living farther away. Spatial sorting analysis demonstrates no evidence that healthier individuals are more likely to move closer to hospitals. This paper contributes to the understanding of the drivers of health inequality and highlights the importance of geographic factors in influencing health outcomes and health inequality
Master Thesis: Life Satisfaction Profile Comparative Study: Immigrants and Native-born Canadians
Presentations/policy impacts:
NSW loneliness inquiry 2024
United States Patent and Trademark Office (USPTO) Chief Economist Speaker Series, Sept, 2021
IP Day at Boston University. U.S., July 2021
Canada Economic Association, Vancouver, Canada. June 2021
The Innovation Information Initiative working meetings (Sloan Foundation), U.S. 2020
University of Queensland, Brisbane, Australia 2020
Workshop on the Economics of Health and Wellbeing, Melbourne, Australia 2020
BEST Conference on Human Behaviour & Decision Making, Brisbane, Australia 2020
Intellectual Property and Education in the Age of COVID-19, Brisbane, Australia 2020
Knowledge and Innovation Workshop, Brisbane, Australia 2020
Behavioural Insights in Medical Technology and Practice, Brisbane, Australia 2020
International Health Economics Association Conference, Basil, Switzerland 2019
Inequality of Opportunity Conference, Brisbane, Australia, Jun, 2019
Canada Economic Association, Banff, Canada. May 2019
Australian Gender Economics Workshop, Melbourne, Australia, Feb, 2019
Australian Health Economic Society Annual Conference, Hobart, Australia, Sept 2018
International Association for Research in Income and Wealth, Copenhagen, Denmark. Aug 2018
Canadian Economic Association Annual Conference, Montreal, Canada, Jun 2018
Invited Seminar: Melbourne University, Melbourne, Australia, Melbourne, Australia, Feb, 2018
Western Economic Association International Meeting, New Castle, Australia, Juan, 2018
Australian Health Economic Society Annual Conference, Sydney, Australia, Sept, 2017
Invited Seminar: University of New Brunswick, Fredericton, Canada, Jan, 2017
Atlantic Canada Economics Association, Sackville, NB. Canada Oct 2016
International Association for Research in Income and Wealth, Dresden, Germany. Aug 2016
Western Economic Association International Meeting, Portland (OR). US. Jul 2016
Canadian Economic Association. Toronto, Canada. May 2015
Atlantic Canada Economics Association, Wolfville, Canada Oct 2015
Atlantic Canada Economics Association, Truro, Canada Oct 2014
Atlantic Canada Economics Association, St. Johns, Canada Oct 2013
Canadian Economic Association. Montreal, Canada Jun 2013