Essays on employments and wages in the online labour market

This thesis consists of three empirical papers, which focus on jobs and wage setting in the online labour market. The first paper employs a sample of 38,945 gender-targeted online job vacancies in Vietnam from February 2019 to July 2020 to investigate gender differences in returns to physical attractiveness. In particular, we compare the monthly offered wage in matched vacancies with and without beauty preferences of the same characteristics among job ads directed at men and women separately. We find evidence that better-looking women enjoy a wage premium of up to 5.2 percent, whereas better-looking men do not. Earning premia for attractive women is present not only among occupations with intensive social interactions where beauty is expected to enhance performance but also among other occupations. We also document substantial heterogeneity in returns to look across education, experience levels, job positions and job locations. The second paper uses a unique dataset of online job vacancies from February 2019 to July 2020 to examine wage dollarisation – the use of foreign currency for salary setting. We first document that employers advertise wages in US dollars to search for highly-skilled workers. Additionally, we employ matching techniques to investigate the relationship between wage and exchange rate benefits offered by jobs quoting salary in US dollars. Our results reveal that there is a complementarity between wage and exchange rate benefits. The positive wage effect of exchange rate benefits is highest in lower-position jobs as well as jobs of lower education and experience levels. The third paper examines the wage gap between the formal and informal job sectors using online job vacancies data from February 2019 to July 2020. First, we identify a job posting as informal if it shows discrimination against the worker’s (i) marital status, (ii) gender and (iii) disability. Second, we employ various matching techniques and estimate the wage gap between formal and informal employment in the matched samples. Our findings suggest that informal jobs tend to offer a lower salary than their formal counterparts. In particular, the study shows significant wage premia of 1.6 to 1.9 percent for formal jobs and wage penalties of 0.8 to 21.4 percent for informal jobs. Furthermore, we find that the wage gap between formal and informal jobs is highly heterogeneous across different job types

Local crime and prosocial attitudes : evidence from charitable donations

Combining longitudinal postcode-level data on charitable donations made through a UK giving portal with publicly available data on local crime and neighborhood characteristics, we study the relationship between local crime and local residents’ charitable giving and we investigate the possible mechanisms underlying this relationship. An increase in local crime corresponds to a sizeable increase in the overall size of unscheduled charitable donations. This effect is mainly driven by the responses of female and gender unclassified donors. Donation responses also reflect postcode variation in socio-economic characteristics, levels of mental health, and political leanings, but mainly so for female and gender-unidentified donors

The ongoing value of first few X studies for COVID-19 in the Western Pacific Region

First few ‘X’ (FFX) studies for COVID-19 involve data collection from confirmed cases and their close contacts. They remain relevant especially as many remain susceptible to infection, and as they can provide detailed insight into vaccine effectiveness and the epidemiology of variants of concern, helping to inform a proportionate health response

The Impact of Social Presence in the Web Interface on Customer's Purchase Intention toward Online Stores: The Case of Vietnam

Abstract To date the expansion of information systems in the wa

Understanding COVID-19 Dynamics and the Effects of Interventions in the Philippines: A Mathematical Modelling Study

Background COVID-19 initially caused less severe outbreaks in many low- and middle-income countries (LMIC) compared with many high-income countries; possibly because of differing demographics; socioeconomics; surveillance; and policy responses. Here; we investigate the role of multiple factors on COVID-19 dynamics in the Philippines; a LMIC that has had a relatively severe COVID-19 outbreak. Methods We applied an age-structured compartmental model that incorporated time-varying mobility; testing; and personal protective behaviors (through a “Minimum Health Standards” policy; MHS) to represent the first wave of the Philippines COVID-19 epidemic nationally and for three highly affected regions (Calabarzon; Central Visayas; and the National Capital Region). We estimated effects of control measures; key epidemiological parameters; and interventions. Findings Population age structure; contact rates; mobility; testing; and MHS were sufficient to explain the Philippines epidemic based on the good fit between modelled and reported cases; hospitalisations; and deaths. The model indicated that MHS reduced the probability of transmission per contact by 13-27%. The February 2021 case detection rate was estimated at ~8%; population recovered at ~9%; and scenario projections indicated high sensitivity to MHS adherence. Interpretation COVID-19 dynamics in the Philippines are driven by age; contact structure; mobility; and MHS adherence. Continued compliance with low-cost MHS should help the Philippines control the epidemic until vaccines are widely distributed; but disease resurgence may be occurring due to a combination of low population immunity and detection rates and new variants of concern

Sustaining effective COVID-19 control in Malaysia through large-scale vaccination

Introduction: As of 3rd June 2021, Malaysia is experiencing a resurgence of COVID-19 cases. In response, the federal government has implemented various non-pharmaceutical interventions (NPIs) under a series of Movement Control Orders and, more recently, a vaccination campaign to regain epidemic control. In this study, we assessed the potential for the vaccination campaign to control the epidemic in Malaysia and four high-burden regions of interest, under various public health response scenarios. Methods: A modified susceptible-exposed-infectious-recovered compartmental model was developed that included two sequential incubation and infectious periods, with stratification by clinical state. The model was further stratified by age and incorporated population mobility to capture NPIs and micro-distancing (behaviour changes not captured through population mobility). Emerging variants of concern (VoC) were included as an additional strain competing with the existing wild-type strain. Several scenarios that included different vaccination strategies (i.e. vaccines that reduce disease severity and/or prevent infection, vaccination coverage) and mobility restrictions were implemented. Results: The national model and the regional models all fit well to notification data but underestimated ICU occupancy and deaths in recent weeks, which may be attributable to increased severity of VoC or saturation of case detection. However, the true case detection proportion showed wide credible intervals, highlighting incomplete understanding of the true epidemic size. The scenario projections suggested that under current vaccination rates complete relaxation of all NPIs would trigger a major epidemic. The results emphasise the importance of micro-distancing, maintaining mobility restrictions during vaccination roll-out and accelerating the pace of vaccination for future control. Malaysia is particularly susceptible to a major COVID-19 resurgence resulting from its limited population immunity due to the country's historical success in maintaining control throughout much of 2020

COVID-19 collaborative modelling for policy response in the Philippines, Malaysia and Vietnam

Mathematical models that capture COVID-19 dynamics have supported public health responses and policy development since the beginning of the pandemic, yet there is limited discourse to describe features of an optimal modelling platform to support policy decisions or how modellers and policy makers have engaged with each other. Here, we outline how we used a modelling software platform to support public health decision making for the COVID-19 response in the Western Pacific Region (WPR) countries of the Philippines, Malaysia and Viet Nam. This perspective describes an approach to support evidence-based public health decisions and policy, which may help inform other responses to similar outbreak events. The platform we describe formed the basis for one of the inaugural World Health Organization (WHO) Western Pacific (WPRO) Innovation Challenge awards, and was backed by collaboration between epidemiological modellers, those providing public health advice, and policy makers

The influence of human genetic variation on early transcriptional responses and protective immunity following immunization with Rotarix vaccine in infants in Ho Chi Minh City in Vietnam : a study protocol for an open single-arm interventional trial [awaiting peer review]

Background: Rotavirus (RoV) remains the leading cause of acute gastroenteritis in infants and children aged under five years in both high- and low-middle-income countries (LMICs). In LMICs, RoV infections are associated with substantial mortality. Two RoV vaccines (Rotarix and Rotateq) are widely available for use in infants, both of which have been shown to be highly efficacious in Europe and North America. However, for unknown reasons, these RoV vaccines have markedly lower efficacy in LMICs. We hypothesize that poor RoV vaccine efficacy across in certain regions may be associated with genetic heritability or gene expression in the human host. Methods/design: We designed an open-label single-arm interventional trial with the Rotarix RoV vaccine to identify genetic and transcriptomic markers associated with generating a protective immune response against RoV. Overall, 1,000 infants will be recruited prior to Expanded Program on Immunization (EPI) vaccinations at two months of age and vaccinated with oral Rotarix vaccine at two and three months, after which the infants will be followed-up for diarrheal disease until 18 months of age. Blood sampling for genetics, transcriptomics, and immunological analysis will be conducted before each Rotarix vaccination, 2-3 days post-vaccination, and at each follow-up visit (i.e. 6, 12 and 18 months of age). Stool samples will be collected during each diarrheal episode to identify RoV infection. The primary outcome will be Rotarix vaccine failure events (i.e. symptomatic RoV infection despite vaccination), secondary outcomes will be antibody responses and genotypic characterization of the infection virus in Rotarix failure events. Discussion: This study will be the largest and best powered study of its kind to be conducted to date in infants, and will be critical for our understanding of RoV immunity, human genetics in the Vietnam population, and mechanisms determining RoV vaccine-mediated protection. Registration: ClinicalTrials.gov, ID: NCT03587389. Registered on 16 July 2018