Does intra-firm bargaining matter for business cycle dynamics?

We analyse the implications of intra-firm bargaining for business cycle dynamics in models with large firms and search frictions. Intra-firm bargaining implies a feedback effect from the marginal revenue product to wage setting which leads firms to over-hire in order to reduce workers' bargaining position within the firm. The key to this effect are decreasing returns and/or downward-sloping demand. We show that equilibrium wages and employment are higher in steady state compared to a bargaining framework in which firms neglect this feedback. However, the effects of intra-firm bargaining on adjustment dynamics, volatility and comovement are negligible. --Strategic wage setting,search and matching frictions,business cycle propagation

On-the-job search and the cyclical dynamics of the labor market

We show how on-the-job search and the propagation of shocks to the economy are intricately linked. Rising search by employed workers in a boom amplifies the incentives of firms to post vacancies. In turn, more vacancies induce more on-the-job search. By keeping job creation costs low for firms, on-the-job search greatly amplifies shocks. In our baseline calibration, this allows the model to generate fluctuations of unemployment, vacancies, and labor productivity whose magnitudes are close to the data, and leads output to be highly autocorrelated. --Search and matching,job-to-job mobility,worker flows,Beveridge curve,business cycle,propagation

Long-run growth expectations and "global imbalances" : [January 5, 2011]

This paper examines to what extent the build-up of "global imbalances" since the mid-1990s can be explained in a purely real open-economy DSGE model in which agents’ perceptions of long-run growth are based on filtering observed changes in productivity. We show that long-run growth estimates based on filtering U.S. productivity data comove strongly with long-horizon survey expectations. By simulating the model in which agents filter data on U.S. productivity growth, we closely match the U.S. current account evolution. Moreover, with household preferences that control the wealth effect on labor supply, we can generate output movements in line with the data. JEL Classification: E13, E32, D83, O4

On-the-job search and the cyclical dynamics of the labor market

We show how on-the-job search and the propagation of shocks to the economy are intricately linked. Rising search by employed workers in a boom amplifies the incentives of firms to post vacancies. In turn, more vacancies increases job search. By keeping job creation costs low for firms, on-the-job search greatly amplifies shocks. In our baseline calibration, this allows the model to generate fluctuations of unemployment, vacancies, and labor productivity whose magnitudes are close to the data, and leads output to be highly autocorrelated. JEL Classification: E21, E32, J64business cycle, job-to-job mobility, propagation, Search and matching, worker flows Beveridge curve

Long-run growth expectations and 'global imbalances'

This paper examines to what extent the build-up of 'global imbalances' since the mid-1990s can be explained in a purely real open-economy DSGE model in which agents' perceptions of long-run growth are based on filtering observed changes in productivity. We show that long-run growth estimates based on filtering U.S. productivity data comove strongly with long-horizon survey expectations. By simulating the model in which agents filter data on U.S. productivity growth, we closely match the U.S. current account evolution. Moreover, with household preferences that control the wealth effect on labor supply, we can generate output movements in line with the data. --open economy DSGE models,trend growth,Kalman filter,real-time data,news and business cycles,current account

Aggregate Hours Adjustment in Frictional Labor Markets

We evaluate the ability of the labor market search and matching framework to account for the variation in aggregate hours worked. The model we develop and estimate features search frictions in the labor market, capital and investment adjustment costs, as well as variable hours at the worker level. Firms and workers bargain efficiently over wages and hours worked, and relative price setting is monopolistic. Driving forces of aggregate fluctuations are assumed to be productivity, preference, markup, and investment-specic shocks. We estimate the model on aggregate and labor market data for the U.S. using Bayesian techniques. We find that product market (markup) shocks are important to explain aggregate employment dynamics. We explore various mechanisms that help match the hours worked/employment correlation

The Expectations-Driven U.S. Current Account

Since 1991, survey expectations of long-run output growth for the U.S. relative to the rest of the world exhibit a pattern strikingly similar to that of the U.S. current account, and thus also to global imbalances. We show that this finding can to a large extent be rationalized in a two-region stochastic growth model simulated using expected trend growth filtered from observed productivity. In line with the intertemporal approach to the current account, a major part of the buildup of the U.S. current account deficit appears to be driven by the optimal response of households and firms to improved growth prospects

A successful approach to disperse MWCNTs in polyethylene by melt mixing using polyethylene glycol as additive

An additive-assisted one-step melt mixing approach was developed to produce nanocomposites based on linear low density polyethylene (LLDPE) with multiwalled carbon nanotube (MWCNT). The polymer granules, nanotube powder (2 wt% Nanocyl™ NC7000) and 1-10 wt% of the non-ionic additives poly(ethylene glycol) (PEG) or poly(ethylene oxide) (PEO) with molar masses between 100 g/mol and 100,000 g/mol were simply fed together in the hopper of a small-scale DSM Xplore 15 twin-screw microcompounder. The produced MWCNT/LLDPE composites showed excellent MWCNT dispersion and highly improved electrical properties as compared to samples without the additive, whereas the effects depend on the amount and molar mass of the additive. When 7 wt% PEG (2000 g/mol) were used, a reduction of the electrical percolation threshold from 2.5 wt% to 1.5 wt% was achieved. © 2012 Elsevier Ltd. All rights reserved

Influence of feeding conditions in twin-screw extrusion of PP/MWCNT composites on electrical and mechanical properties

The influence of feeding conditions of multiwalled carbon nanotube (MWCNT) materials, namely Baytubes® C150P and Nanocyl™ NC7000, into polypropylene (PP) was investigated with respect to achieving suitable nanotube dispersion, high electrical conductivity, and good mechanical properties. Both MWCNT materials were fed at selected concentrations either in the hopper of the twin-screw extruder or using a side feeder under otherwise identical extrusion conditions (rotation speed, throughput, temperature profile) using a Berstorff ZE 25 twin-screw extruder. Afterwards, injection molding was performed under identical conditions. The results indicate that the more compact Baytubes® C150P agglomerates should be added into the hopper, as the dispersion assessed by light microscopy is better, electrical resistivities measured on compression and injection molded samples are lower, and elastic modulus, yield strength and impact strength are higher as compared to side feeding. On the other hand, for the more loosely packed Nanocyl™ NC7000 agglomerates, addition using the side feeder leads to better dispersion, lower electrical resistivity, and higher mechanical properties. © 2011 Elsevier Ltd

Community Seismic Network

The article describes the design of the Community Seismic Network, which is a dense open seismic network based on low cost sensors. The inputs are from sensors hosted by volunteers from the community by direct connection to their personal computers, or through sensors built into mobile devices. The server is cloud-based for robustness and to dynamically handle the load of impulsive earthquake events. The main product of the network is a map of peak acceleration, delivered within seconds of the ground shaking. The lateral variations in the level of shaking will be valuable to first responders, and the waveform information from a dense network will allow detailed mapping of the rupture process. Sensors in buildings may be useful for monitoring the state-of-health of the structure after major shaking