Subduction Duration and Slab Dip

The dip angles of slabs are among the clearest characteristics of subduction zones, but the factors that control them remain obscure. Here, slab dip angles and subduction parameters, including subduction duration, the nature of the overriding plate, slab age, and convergence rate, are determined for 153 transects along subduction zones for the present day. We present a comprehensive tabulation of subduction duration based on isotopic ages of arc initiation and stratigraphic, structural, plate tectonic and seismic indicators of subduction initiation. We present two ages for subduction zones, a long‐term age and a reinitiation age. Using cross correlation and multivariate regression, we find that (1) subduction duration is the primary parameter controlling slab dips with slabs tending to have shallower dips at subduction zones that have been in existence longer; (2) the long‐term age of subduction duration better explains variation of shallow dip than reinitiation age; (3) overriding plate nature could influence shallow dip angle, where slabs below continents tend to have shallower dips; (4) slab age contributes to slab dip, with younger slabs having steeper shallow dips; and (5) the relations between slab dip and subduction parameters are depth dependent, where the ability of subduction duration and overriding plate nature to explain observed variation decreases with depth. The analysis emphasizes the importance of subduction history and the long‐term regional state of a subduction zone in determining slab dip and is consistent with mechanical models of subduction

Homeownership and Unemployment Duration

We examine the effects of homeownership on individuals' unemployment durations in the USA. We take into account that an unemployment spell can terminate with a job or with a non-participation transition. The endogeneity of homeownership is addressed through the estimation of a full maximum likelihood function which jointly models the competing hazards and the probability of being a homeowner. Unobserved factors contributing to the probability of being a homeowner are allowed to be correlated with unobservable heterogeneity in the hazard rates. We find that unemployed homeowners are less likely to find a job than renters. The effect is small but statistically significant for most specifications. The effect is stronger for outright owners and weaker for mortgage holders. We also find that outright owners have a higher and mortgage holders a lower probability of exiting to non-participation than renters

A Short duration Industrial Project Scheme

The aims and implementation of a short-duration industrial project program run at the University of Sheffield is discussed. The project is designed for second-year undergraduates studying electronic and electrical engineering and lasts for seven days. Topics covered include the selection of suitable projects, the project briefing, the investigation of a problem, the project presentation, report, and project appraisal. Examples of specific problems that have been tackled are included, and the future of the program is examine

The Timaeus on Types of Duration

published or submitted for publicatio

Estimating Unemployment Duration

macroeconomics, unemployment

Risk and duration

Interest rates ; Government securities ; Risk