The Recall and New Job Search of Laid-off Workers: A Bivariate Proportional Hazard Model with Unobserved Heterogeneity

Workers who lose their jobs can become re-employed either by being recalled to their previous employers or by finding new jobs. Workers' chances for recall should influence their job search strategies, so the rates of exit from unemployment by these two routes should be directly related. We solve a job search model to establish, in theory, a negative relationship between the recall and new job hazard rates. We look for evidence in the PSID by estimating a semi-parametric competing risks model with explicitly related hazards. We find only a small negative behavioral relationship between recall and new job hazard rates.

"The Minimum Wage and the Employment of Youth: Evidence from the NLSY"

Using panel data on individuals from the National Longitudinal Survey of Youth, we find that employed individuals who were affected by the increases in the federal minimum wage in 1979 and 1980 were 3 to 4% less likely to be employed a year later, even after accounting for the fact that workers employed at the minimum wage may differ from their peers in unobserved ways. These results were obtained using a methodology similar in spirit 10 Card's recent work on the topic, although we use individual rather than state-level data, and an earlier time period.

The effect of population aging on aggregate labor supply in the United States

Output growth is determined by growth in labor productivity and growth in labor input. Over the past two decades, technological developments have changed how many economists think about growth in labor productivity. However, in the coming decades, the aging of the population will change how economists think about the growth in labor input in the United States. As the oldest baby boomers born in 1946 turned 50, then 55, and then 60, an important economic change has slowly surfaced: these people have become less likely to participate in the labor force. While this shift was obscured by a labor market slump in 2002, the aging of the American population began to put downward pressure on aggregate labor supply, marking the start of what is likely to be a sharp deceleration in labor input that will last another half-century.Labor supply ; Baby boom generation

Do We Know Why Earnings Fall with Job Displacement?

After being displaced from their jobs, workers experience reduced earnings for many years and are at greater risks of other problems as well. The ills suffered by displaced workers motivated several recent expansions of government programs, including the unemployment insurance system, and have spurred calls for wage insurance that would provide longer-run earnings replacement. However, while the average size and the individual characteristics associated with the losses are relatively clear, the theory of displacement-induced earnings loss is scattered. Much of the policy discussion appears to interpret displacement-induced losses through the lens of specific human capital theory, in which skills are specific to jobs, locations, industries, or occupations, and that model has considerable empirical support. Assistance for displaced workers may improve well-being in that model since it insures workers against the risk that their consumption of goods and services might fall for idiosyncratic reasons and, as a consequence, allows workers to make more productive but higher-risk career choices. But there are other credible theories of costly job displacement that have different causal mechanisms, different interpretations and different policy implications. This paper reviews theories of costly job displacement and discusses their consistency with the available empirical evidence. We find that while specific human capital is important, we cannot rule out important roles for other theories

Relationships between hornblende K-Ar ages, chemical composition and hydrogen isotopes, Connemara, western Ireland: evidence for a massive extinct hydrothermal system

Major element compositional analyses, K-Ar ages, deltaD parts per thousand and delta O-18 parts per thousand values for 30 zoned and unzoned hornblendes from Dalradian amphibolites and metagabbros. mostly in north Connemara are reported. Although the cooling ages are expected from previous U-Pb zircon studies to be c. 475-450 Ma the results obtained are from 556 +/- 6 to 410 +/- 9 Ma with an average of 470 Ma. Fluid movements. probably at 275 +/- 15 degreesC, i.e. much below Ar closure temperature for hornblende. erratically reset the ages, as is shown by a negative correlation of hornblende deltaD and age and a wide scatter of ages even within 2 m. The changes were implemented by deltaD exchange between fluid and hornblendes in which ionic porosity. Z, influenced the loss of Ar and possibly its gain from the fluid to give the excess Ar found in some samples. Z is controlled by hornblende chemical composition. High Mg, Si and Mg/Fe and low Fe, Al, Ti, Na and particularly low K, amphiboles giving low Z values retained Ar more firmly and gained Ar more readily than compositions which had higher Z values, which gave younger ages. These range down to c, 400 Ma. being the age of the intrusion of the Galway Granite suite that initiated the fluid circulation. The scatter of ages is a consequence of incomplete equilibration, mainly because of the slow deltaD exchange rate below 350 degreesC and partly because the fluid permeated erratically in different areas and down cracks of all kinds, promoting irregular Ar movement. The meteoric fluid circulated through Connemara. the Galway Granite and at least some of the contiguous Silurian sediments of the South Mayo trough. These overlying sediments may have contributed to the water circulated in north Connemara which was slightly less negative deltaD than in central Connemara. For hornblende K-Ar ages to be a reliable measure of times of uplift and cooling, they need to be demonstrated to be free from the influence of hot fluids by showing no correlation of age with deltaD

Note on the importance of hydrocarbon fill for reservoir quality prediction in sandstones

Oil emplacement retarded the rate of quartz cementation in the Brae Formation deep-water sandstone reservoirs of the Miller and Kingfisher fields (United Kingdom North Sea), thus preserving porosity despite the rocks' being buried to depths of 4 km and 120degreesC. Quartz precipitation rates were reduced by at least two orders of magnitude in the oil legs relative to the water legs. Important contrasts in quartz cement abundances and porosities have emerged between the oil and water legs where reservoirs have filled with hydrocarbons gradually over a prolonged period of time (greater than 15 m.y.). The earlier the hydrocarbon fill, the greater is the degree of porosity preservation. Failure to consider this phenomenon during field development could lead to overestimation of porosity and permeability in the water leg, potentially leading in turn to poor decisions about the need for and placement of downflank water injectors. During exploration, the retarding effect of oil on quartz cementation could lead to the presence of viable reservoirs situated deeper than the perceived regional economic basement

A composite C-isotope profile for the Neoproterozoic Dalradian Supergroup of Scotland and Ireland

The Neoproterozoic Dalradian Supergroup is a dominantly siliciclastic metasedimentary succession in the Caledonian orogenic belt of Scotland and Ireland. Despite polyphase deformation and greenschist- to upper amphibolite-facies metamorphism, carbonate units distributed throughout the Dalradian record marked δ13Ccarbonate excursions that can be linked to those associated with key environmental events of Neoproterozoic time. These include: (1) tentative correlation of the Ballachulish Limestone with the c. 800 Ma Bitter Springs anomaly; (2) the presence of the pre-Marinoan Trezona anomaly and 635 Ma marinoan-equivalent cap carbonat sequence in rocks of the middle Easdale Subgroup; (3) the terminal proterozoic (c. 600-551 Ma)Wonoka-Shuram anomaly in the Girlsta Limestone on Shetland. These linkages strengthen previously inferred correlations of the Stralinchy-Reelan formations and the Inishowen-Loch na Cille-MacDuff ice-rafted debris beds to the respectively 635 Ma Marinoan and 582 Ma Gaskiers glaciations, and suggest that the oldest Dalradian glacial unit, the Port Askaig Formation, represents one of the c. 750-690 Ma Sturtian glacial episodes. These δ13C data and resulting correlations provide more robust constraints on the geological evolution of the Dalradian Supergroup than anything hitherto available and enhance its utility in helping refine understanding of Neoprotrozoic Earth history

⁸⁷Sr/⁸⁶Sr chemostratigraphy of Neoproterozoic Dalradian limestones of Scotland and Ireland: constraints on depositional ages and time scales

New calcite <sup>87</sup>Sr/<sup>86</sup>Sr data for 47 limestones from the metamorphosed and deformed Neoproterozoic-Cambrian Dalradian Supergroup of Scotland and Ireland are used to identify secular trends in seawater <sup>87</sup>Sr/<sup>86</sup>Sr through the Dalradian succession and to constrain its depositional age. Dalradian limestones commonly have Sr greater than 1000 ppm, indicating primary aragonite and marine diagenesis. Low Mn, Mn/Sr less than 0.6, ë<sup>18</sup>O and trace element data indicate that many <sup>87</sup>Sr/<sup>86</sup>Sr ratios are unaltered since diagenesis despite greenschist- to amphibolite-facies metamorphism, consistent with the documented behaviour of Sr and O during metamorphic fluid-rock interaction. Thus, the <sup>87</sup>Sr/<sup>86</sup>Sr data are interpreted largely to reflect <sup>87</sup>Sr/<sup>86</sup>Sr of coeval seawater. Currently available data show that Neoproterozoic seawater <sup>87</sup>Sr/<sup>86</sup>Sr rose from c. 0.7052 at 850-900 Ma to c. 0.7085 or higher in the latest Neoproterozoic. Temporal changes at c. 800 Ma and c . 600 Ma bracket the range in <sup>87</sup>Sr/<sup>86</sup>Sr values of calcite in Grampian. Appin and lowest Argyll Group (c.0.7064-0.7072) and middle and uppermost Argyll Group (c. 0.7082-0.7095) limestones, consistent with a rise in seawater <sup>87</sup>Sr/<sup>86</sup>Sr around 600 Ma. <sup>87</sup>Sr/<sup>86</sup>Sr data are consistent with the sedimentary affinity of the Islay Subgroup with the underlying Appin Group, and with a possible time interval between deposition of Islay and Easdale Subgroup rocks. They indicate that the Dalradian, as a whole, is younger than c. 800 Ma