Returns to Tenure or Seniority?

This study documents two empirical regularities, using data for Denmark and Portugal. First, workers who are hired last, are the first to leave the firm (Last In, First Out; LIFO). Second, workers’ wages rise with seniority (= a worker’s tenure relative to the tenure of her colleagues). We seek to explain these regularities by developing a dynamic model of the firm with stochastic product demand and hiring cost (= irreversible specific investments). There is wage bargaining between a worker and its firm. Separations (quits or layoffs) obey the LIFO rule and bargaining is efficient (a zero surplus at the moment of separation). The LIFO rule provides a stronger bargaining position for senior workers, leading to a return to seniority in wages. Efficiency in hiring requires the workers’ bargaining power to be in line with their share in the cost of specific investment. Then, the LIFO rule is a way to protect their property right on the specific investment. We consider the effects of Employment Protection Legislation and risk aversion.irreversible investment, efficient bargaining, seniority, LIFO, matched employer-employee data, EPL.

Returns to Tenure or Seniority?

This study documents two empirical regularities, using data for Denmark and Portugal. First, workers who are hired last, are the first to leave the firm (Last In, First Out; LIFO). Second, workers' wages rise with seniority (= a worker's tenure relative to the tenure of her colleagues). We seek to explain these regularities by developing a dynamic model of the firm with stochastic product demand and hiring cost (= irreversible specific investments). There is wage bargaining between a worker and its firm. Separations (quits or layoffs) obey the LIFO rule and bargaining is efficient (a zero surplus at the moment of separation). The LIFO rule provides a stronger bargaining position for senior workers, leading to a return to seniority in wages. Efficiency in hiring requires the workers’bargaining power to be in line with their share in the cost of specific investment. Then, the LIFO rule is a way to protect their property right on the specific investment. We consider the e¤ects of Employment Protection Legislation and risk aversion.irreversible investment; efficient bargaining; seniority; LIFO

Tenure Profiles and Efficient Separation in a Stochastic Productivity Model

This paper provides a new way of analyzing tenure profiles in wages, by modelling simultaneously the evolution of wages and the distribution of tenures. Starting point is the observation that within-job log wages for an individual can be described by random walk. We develop a theoretical model based on efficient bargaining, where both log outside wage and log wage in the current job follow a random walk. This setting allows the application of real option theory. We derive the efficient separation rule, which stipulates that workers switch jobs when the difference between the outside wage and the wage in the current job reaches a threshold. The model fits well the observed distribution of job tenures. Since we observe outside wages only at job start and job separation, our empirical analysis of with job wage growth is based on expected wage growth conditional on the outside wages at both dates. Our modelling allows testing of the efficient bargaining hypothesis. The model is estimated on the PSID

Returns to tenure or seniority?

This study documents two empirical regularities, using data for Denmark and Portugal. First, workers who are hired last, are the first to leave the firm (Last In, First Out; LIFO). Second, workers’ wages rise with seniority (= a worker’s tenure relative to the tenure of her colleagues). We seek to explain these regularities by developing a dynamic model of the firm with stochastic product demand and hiring cost (= irreversible specific investments). There is wage bargaining between a worker and its firm. Separations (quits or layoffs) obey the LIFO rule and bargaining is efficient (a zero surplus at the moment of separation). The LIFO rule provides a stronger bargaining position for senior workers, leading to a return to seniority in wages. Efficiency in hiring requires the workers’ bargaining power to be in line with their share in the cost of specific investment. Then, the LIFO rule is a way to protect their property right on the specific investment. We consider the effects of Employment Protection Legislation and risk aversion.NIPE – Núcleo de Investigação em Políticas Económicas – is supported by the Portuguese Foundation for Science and Technology through the Programa Operacional Ciência e Inovação 2010 (POCI 2010) of the III Quadro Comunitário de Apoio (QCA III), which is financed by FEDER and Portuguese funds

Returns to Tenure or Seniority?

This study documents two empirical regularities, using data for Denmark and Portugal. First, workers who are hired last, are the first to leave the firm (Last In, First Out; LIFO). Second, workers’ wages rise with seniority (= a worker’s tenure relative to the tenure of her colleagues). We seek to explain these regularities by developing a dynamic model of the firm with stochastic product demand and hiring cost (= irreversible specific investments). There is wage bargaining between a worker and its firm. Separations (quits or layoffs) obey the LIFO rule and bargaining is efficient (a zero surplus at the moment of separation). The LIFO rule provides a stronger bargaining position for senior workers, leading to a return to seniority in wages. Efficiency in hiring requires the workers’ bargaining power to be in line with their share in the cost of specific i

Greater Blood Pressure Variability Is Associated With Lower Cognitive Performance:The Maastricht Study

An increasing number of individuals will face age-related cognitive difficulties because life expectancy has increased. It is, therefore, important to identify modifiable risk factors for cognitive impairment. Very short-term to mid-term blood pressure variability (BPV) may be such a factor because it may cause cerebral ischemia. To this end, we investigated whether greater systolic and diastolic BPV are cross-sectionally associated with memory function (n=1804), information processing speed (n=1793), and executive function (n=1780) in 40- to 75-year-old individuals from The Maastricht Study. A composite BPV-index was derived by standardizing within-visit, 24-hour, and 7-day BPV. We performed linear regression with adjustments for age, sex, educational level, 24-hour systolic or diastolic pressure, and cardiovascular risk factors. We found that a 1-SD greater systolic BPV was not associated with information processing speed (β [SD difference], -0.10; 95% CI, -0.14 to 0.06), or executive function (-0.09; 95% CI, -0.20 to 0.02) but was marginally associated with lower memory function (-0.11; 95% CI, -0.21 to 0.00). A 1-SD greater diastolic BPV was associated with lower information processing speed (-0.10; 95% CI, -0.20 to -0.00) and executive function (-0.12; 95% CI, -0.22 to -0.01) and marginally associated with lower memory function (-0.09; 95% CI, -0.20 to 0.01). These effects on cognitive performance are equivalent to ≈3 additional years of aging. In conclusion, greater very short-term to mid-term diastolic and, to a lesser extent, systolic BPV may be a modifiable risk factor for cognitive deterioration in 40- to 75-year-old, community-dwelling individuals

The association of white matter connectivity with prevalence, incidence and course of depressive symptoms: The Maastricht Study

BACKGROUND: Altered white matter brain connectivity has been linked to depression. The aim of this study was to investigate the association of markers of white matter connectivity with prevalence, incidence and course of depressive symptoms. METHODS: Markers of white matter connectivity (node degree, clustering coefficient, local efficiency, characteristic path length, and global efficiency) were assessed at baseline by 3 T MRI in the population-based Maastricht Study (n = 4866; mean ± standard deviation age 59.6 ± 8.5 years, 49.0% women; 17 406 person-years of follow-up). Depressive symptoms (9-item Patient Health Questionnaire; PHQ-9) were assessed at baseline and annually over seven years of follow-up. Major depressive disorder (MDD) was assessed with the Mini-International Neuropsychiatric Interview at baseline only. We used negative binominal, logistic and Cox regression analyses, and adjusted for demographic, cardiovascular, and lifestyle risk factors. RESULTS: A lower global average node degree at baseline was associated with the prevalence and persistence of clinically relevant depressive symptoms [PHQ-9 ⩾ 10; OR (95% confidence interval) per standard deviation = 1.21 (1.05-1.39) and OR = 1.21 (1.02-1.44), respectively], after full adjustment. On the contrary, no associations were found of global average node degree with the MDD at baseline [OR 1.12 (0.94-1.32) nor incidence or remission of clinically relevant depressive symptoms [HR = 1.05 (0.95-1.17) and OR 1.08 (0.83-1.41), respectively]. Other connectivity measures of white matter organization were not associated with depression. CONCLUSIONS: Our findings suggest that fewer white matter connections may contribute to prevalent depressive symptoms and its persistence but not to incident depression. Future studies are needed to replicate our findings

Thyrotropin-releasing hormone (TRH) promotes wound re-epithelialisation in frog and human skin

There remains a critical need for new therapeutics that promote wound healing in patients suffering from chronic skin wounds. This is, in part, due to a shortage of simple, physiologically and clinically relevant test systems for investigating candidate agents. The skin of amphibians possesses a remarkable regenerative capacity, which remains insufficiently explored for clinical purposes. Combining comparative biology with a translational medicine approach, we report the development and application of a simple ex vivo frog (Xenopus tropicalis) skin organ culture system that permits exploration of the effects of amphibian skin-derived agents on re-epithelialisation in both frog and human skin. Using this amphibian model, we identify thyrotropin-releasing hormone (TRH) as a novel stimulant of epidermal regeneration. Moving to a complementary human ex vivo wounded skin assay, we demonstrate that the effects of TRH are conserved across the amphibian-mammalian divide: TRH stimulates wound closure and formation of neo-epidermis in organ-cultured human skin, accompanied by increased keratinocyte proliferation and wound healing-associated differentiation (cytokeratin 6 expression). Thus, TRH represents a novel, clinically relevant neuroendocrine wound repair promoter that deserves further exploration. These complementary frog and human skin ex vivo assays encourage a comparative biology approach in future wound healing research so as to facilitate the rapid identification and preclinical testing of novel, evolutionarily conserved, and clinically relevant wound healing promoters

Association of Type 2 Diabetes, According to the Number of Risk Factors Within Target Range, With Structural Brain Abnormalities, Cognitive Performance, and Risk of Dementia

OBJECTIVE: Type 2 diabetes is associated with increased risks of cognitive dysfunction and brain abnormalities. The extent to which risk factor modification can mitigate these risks is unclear. We investigated the associations between incident dementia, cognitive performance, and brain abnormalities among individuals with type 2 diabetes, according to the number of risk factors on target, compared with control subjects without diabetes. RESEARCH DESIGN AND METHODS: Prospective data were from UK Biobank of 87,856 individuals (n = 10,663 diabetes, n = 77,193 control subjects; baseline 2006-2010), with dementia follow-up until February 2018. Individuals with diabetes were categorized according to the number of seven selected risk factors within the guideline-recommended target range (nonsmoking; guideline-recommended levels of glycated hemoglobin, blood pressure, BMI, albuminuria, physical activity, and diet). Outcomes were incident dementia, domain-specific cognitive performance, white matter hyperintensities, and total brain volume. RESULTS: After a mean follow-up of 9.0 years, 147 individuals (1.4%) with diabetes and 412 control subjects (0.5%) had incident dementia. Among individuals with diabetes, excess dementia risk decreased stepwise for a higher number of risk factors on target. Compared with control subjects (incidence rate per 1,000 person-years 0.62 [95% CI 0.56; 0.68]), individuals with diabetes who had five to seven risk factors on target had no significant excess dementia risk (absolute rate difference per 1,000 person-years 0.20 [-0.11; 0.52]; hazard ratio 1.32 [0.89; 1.95]). Similarly, differences in processing speed, executive function, and brain volumes were progressively smaller for a higher number of risk factors on target. These results were replicated in the Maastricht Study. CONCLUSIONS: Among individuals with diabetes, excess dementia risk, lower cognitive performance, and brain abnormalities decreased stepwise for a higher number of risk factors on target