Oaxaca-Blinder Decomposition Research Articles

Union membership and the wage gap between the public and private sectors: evidence from China

As trade unions are active in corporations worldwide, their effects on the labor market have attracted global attention. However, there is scarce empirical evidence regarding how trade unions’ effects on the wage gap differ between the public and private sectors, especially in the Chinese context. Using national longitudinal survey data from the China Family Panel Studies for the years 2010, 2012, 2014, 2016, and 2018 and the Blinder-Oaxaca decomposition method, this study estimates unions’ effect on the wage gap between the public and private sectors in China. The results from the Ordinary Least Squares (OLS) method indicate the existence of a significant positive union wage premium nationwide. Additionally, the premium in the public sector is greater than that in the private sector. However, this effect becomes insignificant after accounting for individual heterogeneity using the fixed effects model. The decomposition results based on the OLS method indicate that the union coverage difference (the endowment effect) widens the wage gap between the public and private sectors; conversely, the union wage premium difference (the price effect) narrows the wage gap. These results indicate that a policy expanding union coverage in the private sector may effectively narrow the wage gap between both sectors.

The impact of the 2017 Collective Bargaining Agreement on wage discrimination in the NBA

ABSTRACT This research re-evaluates wage discrimination in the National Basketball Association (NBA) following the 2017 Collective Bargaining Agreement (CBA) being implemented. Using free agent data, weighted least square regression, and the Oaxaca-Blinder decomposition, our results indicate that race does not significantly predict NBA players’ salaries, on average, after the 2017 CBA went into effect. Nevertheless, quantile regressions show discrimination remains present for star players. The results emphasize the potential positive effects that labour union agreements bring to professional sports labour markets.

Analyzing gender gap in agricultural productivity: Evidence from Ethiopia

Women make up more than 50% of the agricultural labor force but contribute less than 30% to agricultural productivity. Agriculture is the main source of livelihood in Ethiopia but by contributes more than 35% to GDP, 90% to forex earnings, and 70% to employment sources. So Improving economic well-being ensuring sustainable development, and reducing poverty is impossible by ignoring the role of women. Consequently, the main objective of the study is to investigate the gender gap in agricultural productivity using national Panel data of 3474 households which were collected in 2017 and 2019 by the Policy Studies Institute for AGP II baseline study and midline evaluation. Among these, 69% (2404) were male-headed and 31% (1070) were female-headed households. The panel data were combined with DID, Oaxaca Decomposition, and the Random effect Tobit model to investigate the gender gap. The result from the DID Method of Impact Evaluation shows that female-headed households were less productive by 3.7% and 2.05 quintals per hectare when measured in terms of value in birr and quintals per hectare compared to male-headed households. In contrast, male-headed households were more productive by 4% and 2.05 quintals compared to female-headed households. Additionally, the results from the pooled and random effect Tobit model showed that soil fertility, sex of the household head, slope of the land, total livestock holding in TLU, extension contact, use of inorganic fertilizer, credit use, machinery use, and plantation method are among the determinants of the gender gap in agricultural productivity. Furthermore, results from the Oaxaca decomposition show that a gender productivity difference between male and female-headed households was roughly 11.2% when measured by value and 5% when measured by an area-weighted formula. The main finding of the study is that endowment effects were less likely to have a significant impact on the productivity gap than structural effects did. Differences in the unexplained characteristics of men and women may also contribute to the considerable productivity gap between male-headed and female-headed households. Therefore, working on women's empowerment to improve their structural disadvantages through various training programs that favor women or gender-mainstreamed extension training programs for lowering gender productivity differentials is a possible policy option.

Revisiting Earnings Differentials across Socio-religious Groups in the Regular Salaried Employment in India

In India, the differences in a range of development indicators, including wages and earnings, along the spatial, caste, religious and ethnicity lines have been a serious concern. This article revisits the wage disparities and discrimination among regular salaried male workers across five categories of socio-religious groups. Using nationally representative Periodic Labour Force Survey (2018–2019) data, we examine the pattern of disparity and the associated endowment and institutional factors leading to unequal labour market outcomes. Our findings suggest that all the groups—Scheduled Tribes (STs), Scheduled Castes (SCs), Other Backward Classes (OBCs) and Muslims continue to earn significantly lower wages than ‘Others’—the non-ST/SC/OBC/Muslim group. On decomposing the wage gap using the Blinder–Oaxaca decomposition method, we observe that the share of unexplained components reflecting discriminatory treatment continues to be significant. While the wage gap is highest for Muslims and SCs, discrimination is high against SCs and OBCs and lowest against Muslims. Higher education and institutional factors explain a significant proportion of the wage gap for these groups. For STs, urban location and higher education explain most of the differences. In addition, quantile regression results indicate a wider gap at the bottom and a narrower gap at the top of the wage distribution, signalling a ‘sticky-floor’ phenomenon for ST, SC and OBC workers. JEL Codes: E24, J71, J49

THE IMPACT OF ENVIRONMENTAL POLICIES ON CHINESE ENTERPRISES: A COMPARATIVE ANALYSIS OF RESOURCE TAXATION AND ESG ASSESSMENT ON THE FIRM PERFORMANCE AND PRODUCTION BEHAVIOR OF HEAVY POLLUTING ENTERPRISES

This paper investigates and compares the impact of environmental policy and ESG scores in Chinese publicly listed firms. Over the past few years, China has placed greater emphasis on promoting environmental preservation and sustainable growth. It provides an interesting policy system setting for the present research because as a socialist nation, the Chinese government wields significant influence in policymaking. The sample for analysis is 1,117 listed firms in the heavy pollution industry, and the data involves their financial performance and environmental actions between 2012 and 2020. Utilizing time fixed-effects models, lagged effects models, and OaxacaBlinder decomposition, our analysis reveals a robust positive association between environmental policy and financial performance. Additionally, we identify a noteworthy positive implication of ESG scores on both financial and environmental performance. Overall, our evidence suggests that the influence of ESG ratings is prominently stronger than that of policy. This may suggest that policies seem to have limited direct effects on companies, whereas ESG ratings, influenced by capital investments, play a more substantial and beneficial role in enhancing overall corporate performance in these domains.

Do immigrants know less than natives about cancer screening tests? – the case of Netherlands

IntroductionThe Netherlands was one of the first countries in Europe to offer breast, colorectal and cervical cancer screening tests free of charge. Yet, a significant share of migrants in the Netherlands forgo the use of these preventive screenings. Qualitative research suggests, that lack of system knowledge on how the healthcare system operates (e.g. age eligibility of cancer screenings), is one factor contributing to this underuse among migrants. However, little is known about the extent to which migrants differ from natives in their system knowledge and about potential causes of this ethnic gap. The contribution of this study is therefore twofold: First, we examine whether migrants in the Netherlands have lower system knowledge regarding cancer screenings than the natives. Second, we examine which factors explain potential ethnic differences in system knowledge between migrants and non-migrants. MethodUsing the Longitudinal Internet Study for Social Sciences (LISS), we matched newly collected data on system knowledge about healthcare with Health module (wave 14). To assess the difference in system knowledge among migrants and non-migrants, while taking into account potential selection bias, we applied propensity score matching, one-to-one matching procedure with no replacement. We compared first generation non - Western migrants (FNWM) and second-generation non-western migrants (SNWM) with their most similar non-migrants group regarding their knowledge about breast, colorectal, and cervical screening. A Blinder-Oaxaca decomposition with non-matched samples was used to examine which factors can explain the differences in system knowledge among migrants and non-migrants. ResultsOur results show that first generation migrants have lower system knowledge about all three screening tests, while second generation migrants differ from non-migrants only with regard to knowledge about breast and colorectal cancer screenings. The ethnic differences found are not caused by personal or social factors such as education or income. ConclusionWe recommend Dutch healthcare policy makes to focus in the strengthen of cancer screening system knowledge among migrant populations in order to increase their participation in these screening programs.

Examining the Gender Wage Gap between Engineers with Paraprofessional Qualifications versus Undergraduate Degrees in Trinidad and Tobago

The literature on Science, Technology, Engineering, and Mathematics (STEM) field reveals that even with incentives to encourage women into the field of engineering, their level of enrolment and graduation remains low. This study aims to first examine the overall wage returns of all engineers in Trinidad and Tobago and second their gender wage gap at the paraprofessional (certificate/diploma) and undergraduate (first-degree) level of qualifications. Using Labour Force Survey (LFS) data for the 1991-2015 period, the returns of engineers are analysed by estimating a Mincerian earnings equation, and then an Oaxaca-Blinder wage decomposition, using a statistical level of significance, i.e., 0.1% it was found that in the first instance, the earnings of paraprofessional engineers were generally negative (fewer earnings) and significantly smaller than undergraduate engineers. Undergraduate engineers’ earnings appeared to be larger, and positive, and exhibited rising returns, with the highest returns shown at q80 of 18.8%, and the lowest returns at q20 of 13.2%. The earnings of undergraduate female engineers, although higher than their male colleagues, appeared to be falling across the wage distribution, i.e., from 12.7% to 8.2% between q10-q90, but benefit from higher earnings if employed in a low-income job. In the second instance, when looking at the field of engineering as a whole there is a gender wage gap of 1.7%, but when the type/level of qualification is considered, it produces a gender wage gap of 19.6% for engineers with paraprofessional qualifications, and 12.3% for engineers with an undergraduate degree in engineering. The largest gender wage gap is observed amongst engineers holding paraprofessional qualifications. Further analysis into the different components of this gap (unexplained, explained and interaction) reveals that female engineers are more likely to be discriminated against, especially when holding an undergraduate degree in engineering (4.8%), when compared to a paraprofessional qualification (3.6%). Thus, the gender wage gap does not favour female engineers. The paper expands on existing research on the gender wage returns associated with different fields of study and provides detailed evidence of the gender wage gap and the wage patterns emerging from the field of engineering in Trinidad and Tobago, regarding key groups of engineers holding paraprofessional and undergraduate qualifications in the field. It also gives important insights into the earnings of men and women in engineering for the period 1991-2015.

Double burden of malnutrition among women and children in Zimbabwe: a pooled logistic regression and Oaxaca-Blinder decomposition analysis.

The double burden of malnutrition (DBM) is a public health issue characterised by the coexistence of undernutrition and overnutrition within the same population, household, or individual. Undernutrition, manifesting as stunting, wasting, or being underweight, results from insufficient nutrient intake while overnutrition, manifesting as overweight or obesity, results from excessive caloric intake, poor diet quality, and sedentary lifestyles. This dual burden poses significant challenges for health systems due to lost productivity and increased healthcare expenditure. This study utilised data from the Demographic and Health Surveys (DHS) conducted in Zimbabwe for 2010-2011 and 2015, which provided information on women's and children's health and nutritional status, household characteristics, and socio-economic status. Pooled logistic regression was used to analyse the association between various sociodemographic factors and DBM among women and children. The Oaxaca-Blinder decomposition method explored differences in DBM between 2010-2011 and 2015. The average age of mothers was approximately 31 years, and children's ages averaged around 32 months. From 2010 to 2015, there was a notable socio-economic improvement, with a decrease in the percentage of mothers in the poorest quartile from 20 to 16% and an increase in the richest quartile from 22 to 23%. The study found a slight decrease in overall household DBM among women from 34% in 2010 to 32% in 2015, while DBM among children increased from 12 to 14%. Pooled logistic regression analysis indicated that children in rural areas had statistically significantly higher odds of experiencing DBM than their urban counterparts. The Oaxaca-Blinder decomposition showed that changes in residence status significantly impacted the increase in DBM among children. At the same time, the coefficient effect accounted for most of the unexplained differences in DBM among women. The growing DBM among women and children in Zimbabwe is significantly influenced by changes in residence status. The findings highlight the need for targeted public health interventions to address urban-rural disparities and emphasise the importance of considering socio-economic, environmental, and behavioural factors. Context-specific public health strategies, aligned with WHO's Double Duty Actions, are essential to improve the nutritional health of Zimbabwe's population.

Development of Paddy Yield Gap Between Java and Outside Java: Does It Have a Contribution to Paddy Yield Improvement from 2018 to 2021?

Increasing the paddy yield is crucial for Indonesia to maintain its national rice sufficiency amid the consistent depletion of wetland paddy areas. In this regard, the yield disparities between regions are challenging, particularly between Java and outside Java. Our study aims to examine the development of the paddy yield gap between the two regions from 2018 to 2021 and its contribution to paddy yield improvement during the period. Using the results of the National Crop-cutting Survey, we found that while the paddy yield in Java outperformed the paddy yield outside Java, the yield difference between the two regions narrowed from around 26 per cent in 2018 to 22 per cent in 2021 due to the increase of the yield outside Java. The results of the Blinder-Oaxaca decomposition suggested that the narrowing gap has a significant contribution to the national paddy yield increase from 2018 to 2021. Our finding confirms that narrowing the yield gap between the two regions by increasing the yield outside Java is crucial to improving paddy yield in Indonesia. Our study also pointed out that improvement in irrigation systems, fertilizer use, and fertilizer assistance are important factors in maintaining the paddy yield and narrowing the gap.

Gender pay gap in the Czech Republic: focused on management

The existence of a gender pay gap is well known. This paper focuses on the issue of the pay gap in managerial positions. It aims to examine the development of the gender pay gap in managerial positions in the Czech Republic and to identify the unexplained part of the gender pay gap, which could be an indication of gender pay discrimination. To estimate the unexplained part of the gender pay gap data from the European Union Statistics on Income and Living Conditions (EU-SILC) was used and the Oaxaca-Blinder decomposition was applied. The results show that in the period 2005-2019, the average raw gender pay gap in management was 0.22 and the unexplained part was 0.13, using the Neumark’s variant of the decomposition. Differences in women’s and men’s personal and firm characteristics could explain about one-third of the pay gap. The results also suggest that the situation has not changed much over the period considered and that the unexplained part of the gender pay gap has decreased only slightly between 2005 and 2019. Thus, reducing the gender pay gap remains a major challenge for both economic policy makers and companies in promoting corporate social responsibility policies.

Estimating public and private sectors' union wage effects in Ghana: is there a disparity?

PurposeThis study seeks to estimate union wage effect in the public and private sectors of Ghana, respectively. It also seeks to ascertain whether the union wage effect in the two sectors varies.Design/methodology/approachThe authors use data from the Ghana Living Standards Survey 6 (GLSS 6, 2012/2013) and Ghana Labour Force Survey (GLFS, 2015). In terms of estimation technique, the authors employ the Blinder–Oaxaca decomposition technique to estimate union wage effect in public and private sectors, respectively.FindingsThe findings indicate that union wage effect in the public sector is positive and higher relative to that of the private sector.Practical implicationsThe findings imply that strict enforcement of Section 82 of Labour Act 2003 (Act 651) will curb the political influence of public sector unions over their employer (Government).Originality/valueThis research paper has not been presented to any journal for publication and it is the authors' original work.Peer reviewThe peer review history for this article is available at: https://publons.com/publon/10.1108/IJSE-01-2023-0045

Exploring the determinants of the evolution of urban and rural household carbon footprints inequality in China

Households are key actors in mitigating climate change and their carbon footprints are unequally distributed due to differences in the scale and patterns of consumption. This study separately estimates household carbon footprints inequality in urban and rural areas of China from 2012 to 2018 and identifies the factors contributing to the evolution of the inequality by applying environmentally extended multiregional input-output analysis, unconditional quantile regression and Oaxaca-Blinder decomposition. The results show that the largest emission growth occurred among the 50th–80th percentile of urban emitters and the highest rural emitters. The Gini coefficient of urban household carbon footprints decreased from 0.463 to 0.439, whereas that of rural household carbon footprints increased from 0.447 to 0.459. Notably, the changes of household characteristics exacerbated carbon inequality, with income growth, increased car ownership, and smaller household size being the three primary factors, while the changes in consumption preferences and technological advancements reduced carbon inequality. The latter are dominant in urban households and the former are dominant in rural households. To mitigate climate change and reduce inequality, the government should not only encourage high-emitting households to adopt greener low-carbon consumption and lifestyles, but also promote low-carbon technology innovation to reduce carbon intensity.

LONGITUDINAL ASSOCIATION OF COGNITIVE IMPAIRMENTS WITH LATE-LIFE WEALTH CHANGES AMONG OLDER AMERICANS

Abstract Disparities in wealth in the US are linked to disadvantageous health outcomes over the lifecourse. Cognitive impairment can widen wealth disparities. We examine how cognitive impairment influences change in wealth starting in mid-life and into older adulthood and the role of social determinants of health in wealth loss due to cognitive impairment. We use biennial longitudinal data (Health and Retirement Study: 2000-2018) on Non-Hispanic White (NH-W), NH-Black (NH-B), and Hispanic (H) middle-aged adults (51-64 years and cognitively healthy in 2000; unweighted n=3,651) to model wealth change (measured as the relative (%) difference in reported wealth between 2000-2018 [in 2018 dollars]) as a function of cognitive status (using three latent phenotypes derived from longitudinal latent class analyses: cognitively healthy [CH; 77%], increasing cognitive impairment [ICI; 19%], and increasing dementia [ID; 4%]). We fit racial/ethnic stratified regression models to examine relationships between cognitive phenotypes and wealth change, adjusting for covariates. Using Blinder-Oaxaca decomposition techniques, we examined the contributions of predisposing (e.g. race/ethnicity), health enabling (e.g. insurance source), and health needs (i.e. chronic conditions) factors in wealth change by cognitive phenotypes. Results show NH-Ws had higher levels of reported wealth in both 2000 and 2018, compared to NH-Bs and Hs. However, the relative rate of change in wealth was not-significantly different across race/ethnic groups. Education, insurance, and health explained most differences in wealth change related to cognitive impairment. Yet, nearly 50% of group differences in wealth changes remained unexplained. Future work should further elucidate sources of these unexplained differences, overall and by race/ethnicity.

Decomposing the rural-urban disparities in overweight and obesity among women of reproductive age in Nigeria

BackgroundOverweight and obese women face various reproductive and other health challenges, and in some cases, even mortality. Despite evidence of rural-urban disparities in overweight and obesity among women of reproductive age, there is limited evidence regarding the predictors of these disparities. This study aims to investigate the factors associated with overweight and obesity and examine the contributors to rural-urban disparities in overweight and obesity among women of reproductive age in Nigeria.MethodsWe utilized the 2018 Nigeria Demographic and Health Survey dataset. The survey employed a two-stage cluster sampling technique based on Nigeria’s 2006 census enumeration areas for sample selection. Overweight and obesity were defined as a body mass index (BMI) ≥ 25. Data analyses were conducted using the Logistic Regression Model and the threefold Blinder-Oaxaca decomposition model (α0.05).ResultsThe study revealed that older women (OR = 2.44; CI = 2.11–2.83), those with higher wealth (OR = 2.05; CI = 1.81–2.31), contraceptive users (OR = 1.41; CI = 1.27–1.57), and residents of the South-South region (OR = 1.24; CI = 1.07–1.45) were more likely to be overweight/obese. The decomposition analysis indicated that the mean predicted prevalence of overweight and obesity is 35.5% in urban areas, compared to 21.1% in rural areas of Nigeria. Factors such as wealth status, educational level, media exposure, and contraceptive use were identified as significant contributors to these disparities.ConclusionThe findings underscore the importance of addressing socioeconomic disparities when designing healthcare interventions to reduce the burden of overweight and obesity, particularly in urban areas. Prioritizing these factors can facilitate efforts to promote healthier lifestyles and enhance overall well-being.

Rural-urban disparities in nutritional status among ever-married women in Bangladesh: A Blinder-Oaxaca decomposition approach

This study aims to investigate socioeconomic disparities in nutritional status among ever-married women in Bangladesh and to break down urban-rural differences in the underlying causes of undernutrition. We utilized data from the Bangladesh Demographic and Health Survey 2017–18, a sample size of 18328 ever-married women, including 5170 from urban residences, and 13159 from rural residences. To explore socioeconomic inequality, we employed a concentration indexing measure, while a multiple binary logistic regression model was carried out to identify the determinants associated with the outcome variable. A Blinder-Oaxaca decomposition analysis was performed to decompose the urban-rural gap in women’s nutritional status using associated factors. The prevalence of undernutrition among ever-married women in Bangladesh was 12 percent. Notably, this percentage varied by region, with urban residents accounting for 8.6% and rural residents accounting for 13.3%. Our findings confirmed that undernutrition was more prevalent among women with lower wealth indexes in Bangladesh, as indicated by the concentration index (CIX = −0.26). The multivariable analysis investigating the determinants of undernutrition status among ever-married women, with a focus on residence revealed significant associations with respondent age, education, marital status, mass media access, wealth status, and division. According to the Blinder-Oaxaca decomposition and its extension, the prevalence was significantly higher in rural residences of Bangladesh than in urban residences, and the endowment effect explained 86 percent of the total urban-rural difference in undernutrition prevalence. The results of this study indicate that the factors that influence women’s nutritional status in rural areas play a significant role in the gap, and the majority of the gap is caused by education and economic position. In order to effectively promote maternal health policies in Bangladesh, intervention techniques should be created that are aimed at the population, that is, the poorest and least educated.

Social and facilitating influences in fintech user intention and the fintech gender gap

Given the advances in technology, Fintech is an invaluable tool which allows unbanked people to access financial services when social, cultural, economic and technological factors affect their user intentions (UI). Despite the great importance of the role of social and facilitating influences in the adoption of Fintech services, little research has been conducted on how and what influences affect Fintech user intention (FUI) and whether there is a gender gap in FUI. Therefore, this study aims to help formulate effective Fintech policies and close the gender gap by investigating the role of social and facilitating influences and sociodemographic variables in FUI. The study sample comprised 237 participants, and the data were collected through interviews with the use of a structured questionnaire in Chattogram, Bangladesh. The collected data were analysed employing exploratory factor analysis and an ordered logistic regression model. The study also examined the Fintech gender gap by applying the Blinder Oaxaca decomposition model. The results reveal that image, compatibility and the experiences of Fintech use are the positive and significant predictors of FUI, with the perceived social norm for adopting Fintech being non-informative for users. There is a significant interaction between user compatibility and experience of use in relation to Fintech. Interestingly, perceived behavioural control negatively influenced females to adopt Fintech. Furthermore, the study found a gender gap in FUI. The findings have managerial implications.

Gender differences in lead executive compensation: evidence from intercollegiate athletics

ABSTRACT This paper contributes to the literature examining gender differences in executive compensation by assessing whether gender is systematically associated with the guaranteed base salary and maximum potential compensation of the athletic director (AD) who serves as the lead executive of the organization in intercollegiate sport. We utilize National Collegiate Athletic Association compensation data from the United States spanning from 2009 to 2020. We match this with data capturing AD personal characteristics and institutional factors to produce a sample of 613 annual observations. The results from panel regressions and Blinder-Oaxaca decompositions indicate statistically significant evidence that women ADs earn lower base salaries than men ADs after controlling for numerous personal and institutional characteristics. These results suggest potential gender-specific discriminatory treatment in guaranteed compensation. The modeling also produces largely non-significant evidence to suggest women ADs sign employment contracts specifying lower maximum potential compensation values. Overall, the results suggest a sizeable executive compensation gap in a sport setting subject to substantial public awareness and media attention.

Gender Gaps in Financial Literacy: Evidence from Argentina, Chile and Paraguay

Understanding why women are less financially literate than men is crucial for developing effective policies that decrease gender inequalities and improve women’s financial literacy, agency, and empowerment. Accordingly, this article adopts a multidimensional approach to measuring financial literacy in developing countries, aggregating three key components of financial literacy, namely financial behavior, financial attitude, and financial knowledge. Using data from Argentina, Chile, and Paraguay, the study finds that there are statistically significant gender differences in these countries, which is confirmed, except in the case of Chile, by an extensive econometric analysis. In turn, a traditional Oaxaca–Blinder decomposition indicates, when considering the three countries as a whole, that 56 percent of the gap can be attributed to unexplained factors, while 44 percent to differences in observable characteristics, implying that men’s rates of return on human capital components, in a broad sense, are significantly different from those experienced by women. HIGHLIGHTS A comprehensive approach to financial literacy in Argentina, Chile, and Paraguay assesses gender differences in financial behavior, financial attitude, and financial knowledge. Financial literacy is relatively low across all three countries. In Argentina and Paraguay, the gender gap in financial literacy is driven by financial knowledge. Education and income are the largest contributors to the variance in financial literacy.

Analysis of gender wage gap and the Nigerian labour market: a new empirical evidence

PurposeThis study investigated the gender wage gap in Nigeria by analysing two waves of household surveys (in 2003–2004 and 2018–2019) in order to understand the dynamics or polarisation of the labour market in Nigeria in terms of the gender wage gap over time.Design/methodology/approachThe study applied an extension of Oaxaca–Blinder decomposition that relies on the re-centred influence function (RIF) regressions to analyse the gender wage gap at all points along the wage distribution.FindingsThe results unambiguously show that there is a significant gender wage gap in Nigeria at all points along the wage distribution, such that for the two surveys used and after nearly two decades, men still earn more than women. That is, the log wage difference between males and females is statistically significant at all points between the 10th and the 90th quantiles. In 2003–2004 period, the authors found that most of the wage difference was significantly accounted for by the wage structure effect, whilst the composition effect was negative and only significant at the bottom of the wage distribution. Since the 2018–2019 period, the authors found that there has been a visible change such that most of the gender wage gap is now accounted for by the composition effect at all points along the wage distribution. Another interesting finding is that there has been a general decline in the gender wage gap along the entire wage distribution, such that inequality was higher in 2003–2004 than in 2018–2019. This decline is bigger at the top than at the bottom of the wage distribution. The authors also found that, contrary to some of the studies on the wage gap, the raw gaps for the two surveys appear to show inverted U-shape, but the gap has fallen quickly since the 2018–2019 period. Thus, the authors found strong evidence of a “sticky floor” compared to a “glass ceiling” effect in both periods, and this becomes more pronounced over time. In terms of the contributions of individual covariates on gender pay gap in Nigeria, the authors found that urban residence, unionisation, education and occupation variables exhibit major influence. However, the effects of covariates on the composition and wage structure components of the wage gap have changed over time.Practical implicationsThe major policy implication of these findings is that to address the gender wage gap in Nigeria, policy should focus more on how labour is rewarded and improving human capital for women.Originality/valueThis study is a novel paper in Nigeria that has investigated the gender wage gap in Nigeria by extending the focus of literature in three ways. First, the authors applied an extension of Oaxaca–Blinder decomposition that relies on the RIF regressions to analyse the gender wage gap at all points along the wage distribution. Second, the authors used sample selection bias to account for the non-randomness of participation in wage employment. And third, the authors applied similar analysis to two waves of household surveys (in 2003/2004 and 2018/2019) in order to understand the dynamics or polarisation of the labour market in Nigeria in terms of the gender wage gap over time.

Patterns and Life Course Determinants of Black–White Disparities in Biological Age Acceleration: A Decomposition Analysis

Despite the prominence of the weathering hypothesis as a mechanism underlying racialized inequities in morbidity and mortality, the life course social and economic determinants of Black–White disparities in biological aging remain inadequately understood. This study uses data from the Health and Retirement Study (n = 6,782), multivariable regression, and Kitagawa–Blinder–Oaxaca decomposition to assess Black–White disparities across three measures of biological aging: PhenoAge, Klemera–Doubal biological age, and homeostatic dysregulation. It also examines the contributions of racial differences in life course socioeconomic and stress exposures and vulnerability to those exposures to Black–White disparities in biological aging. Across the outcomes, Black individuals exhibited accelerated biological aging relative to White individuals. Decomposition analyses showed that racial differences in life course socioeconomic exposures accounted for roughly 27% to 55% of the racial disparities across the biological aging measures, and racial disparities in psychosocial stress exposure explained 7% to 11%. We found less evidence that heterogeneity in the associations between social exposures and biological aging by race contributed substantially to Black–White disparities in biological aging. Our findings offer new evidence of the role of life course social exposures in generating disparities in biological aging, with implications for understanding age patterns of morbidity and mortality risks.