Do "High Performance" Work Practices Improve Establishment-Level Outcomes?

Interest in the potential effects of different systems for organizing work and managing employees on the performance of organizations has a long history in the social sciences. The interest in economics, arguably more recent, reflects a general concern about the sources of competitiveness in organizations. A number of methodological problems have confronted previous attempts to examine the relationship between work practices and the performance of firms. Among the most intractable has been a concern about establishing causation given heterogeneity biases in what have typically been cross-sectional data. The results from prior literature are suggestive of important productivity effects but remain inconclusive. To address the major methodological problems we use a national probability sample of establishments, measures of work practices and performance that are comparable across organizations, and most importantly a unique longitudinal design incorporating data from a period prior to the advent of high performance work practices. Our results suggest that work practices that transfer power to employees, often described as statistical case is weak. However, we also find that these work practices on average raise labor costs per employee. The net result is no apparent effect on efficiency, a measure that combines labor costs and labor productivity. While these results do not appear to be consistent with the view that such practices are good for employers, neither do they suggest that such practices harm employers. They are, however, consistent with the view that these practices raise average compensation and hence may be good for employees. Overall, then, the evidence suggests that firms can choose raise employee compensation without necessarily harming their competitiveness.

Changes in Managerial Pay Structures 1986-1992 and Rising Returns to Skill

We examine the relationship between wages and skill requirements in a sample of over 50,000 managers in 39 companies between 1986 and 1992. The data include an unusually good measure of job requirements and skills that can proxy for human capital. We find that wage inequality increased both within and between firms from 1986 and 1992. Higher returns to our measure of skill accounts for most of the increasing inequality within firms. At the same time, our measure of skill does not explain much of the cross-sectional variance in average wages between employers, and changes in returns to skill do not explain any of the time series increase in between-firm variance over time. Finally, we find only weak evidence of any declines in the rigidity of internal wage structures of large employers.

External Churning and Internal Flexibility: Evidence on the Functional Flexibility and Core-Periphery Hypotheses

Functionally flexible systems for organizing work may reduce job instability and insecurity by reducing employers’ reliance on job cuts or contingent work to respond to changes in their environments. Related arguments hypothesize that contingent work allows firms to adjust labor while “buffering” their core of permanent workers from job instability. We find evidence that internally flexible work systems are associated with reduced involuntary and voluntary turnover in manufacturing but that contingent work and involuntary turnover of the permanent workforce are positively related regardless of sector, in contrast to the prediction of the core-periphery hypothesis

External Job Churning and Internal Job Flexibility

Concern about job instability and insecurity has a long history and has generated a considerable body of research across the social sciences, most recently focused on whether job stability and security have declined. Internally flexible systems for organizing work, sometimes called 'functionally flexible' systems, have been proposed as arrangements that can reduce job instability and insecurity by reducing the need for firms to rely on job cuts or contingent work to be able to respond to changes in their environments. Related arguments have been made with regard to contingent work - that it allows firms to adjust labor while 'buffering' their core of permanent workers from instability. We examine these arguments using three measures of instability and insecurity - voluntary and involuntary turnover and the use of contingent work - drawn from a national probability sample of establishments. We find evidence that internally flexible work systems are associated with reduced voluntary and involuntary turnover in manufacturing. But in the rest of the economy and indeed overall, they tend to be positively associated with all three measures. Further, the use of contingent work is, in fact, positively related to involuntary turnover even in manufacturing. The evidence therefore suggests that on net employers seeking flexibility in labor tend to use flexible work practices, contingent work, and turnover as complements, while only in manufacturing is there some evidence of substitutability between internal job flexibility and external job churning.

A new class of Matrix Models arising from the W-infinity Algebra

We present a new class of hermitian one-matrix models originated in the W-infinity algebra: more precisely, the polynomials defining the W-infinity generators in their fermionic bilinear form are shown to expand the orthogonal basis of a class of random hermitian matrix models. The corresponding potentials are given, and the thermodynamic limit interpreted in terms of a simple plasma picture. The new matrix models can be successfully applied to the full bosonization of interesting one-dimensional systems, including all the perturbative orders in the inverse size of the system. As a simple application, we present the all-order bosonization of the free fermionic field on the one-dimensional lattice.Comment: 8 pages, 1 figur

Recruitment, Development, and Retention of Dental Faculty in a Changing Environment

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/153771/1/jddj002203372011751tb05026x.pd

Central Charges and U(1)RU(1)_R Symmetries in N=1{\cal N}=1 Super Yang-Mills

We use recent results of Intriligator and Wecht [hep-th/0304128] to study the phase structure of \NN=1 super Yang-Mills theory with gauge group $SU(N_c)$, a chiral superfield in the adjoint, and $N_f$ chiral superfields in the fundamental representation of the gauge group. Our discussion sheds new light on [hep-th/0304128] and supports the conjecture that the central charge $a$ decreases under RG flows and is non-negative in unitary four dimensional conformal field theories.Comment: 35 pages, 14 figures; harvma

Plasma Ceruloplasmin, A Regulator of Nitric Oxide Activity, and Incident Cardiovascular Risk in Patients With CKD

Background and objectives: Increased serum levels of the acute-phase reactant ceruloplasmin predict adverse clinical outcomes in the setting of acute coronary syndromes and heart failure, but their role in patients with CKD is unclear. This study investigated the relationship of ceruloplasmin with clinical outcomes in CKD, especially with regard to traditional cardiac biomarkers. Design, setting, participants, & measurements: Serum ceruloplasmin levels in consecutive study participants with CKD (n=654; estimated GFR\u3c60 ml/min per 1.73 m2) as well as a control group of non-CKD participants matched for age and sex (n=250) were measured. Study participants were enrolled during 2001–2006 from a population of patients presenting for elective diagnostic coronary angiography and prospectively followed for 3 years (median follow-up=1095 days) to determine incident major adverse cardiac events (defined as a composite of death, nonfatal myocardial infarction, and stroke). Results: Serum ceruloplasmin levels in CKD patients were elevated versus controls (median [interquartile range]; 25.5 [21.8–29.6] versus 22.7 [19.7–26.5] mg/dl; P\u3c0.001) and associated with increased risk of future major adverse cardiac events (hazard ratio, 1.35; 95% confidence interval, 1.0 to 1.82; P=0.04). After adjusting for traditional risk factors, higher serum ceruloplasmin was still associated with higher risk of major adverse cardiac events at 3 years (hazard ratio, 1.61; 95% confidence interval, 1.15 to 2.25; P=0.01). Conclusion: In CKD patients, increased serum ceruloplasmin, a regulator of nitric oxide activity, is associated with increased risk of long-term adverse cardiovascular events, even after multivariable model adjustment for traditional clinical and biologic risk factors

Solving Virasoro Constraints on Integrable Hierarchies via the Kontsevich-Miwa Transform

We solve Virasoro constraints on the KP hierarchy in terms of minimal conformal models. The constraints we start with are implemented by the Virasoro generators depending on a background charge $Q$. Then the solutions to the constraints are given by the theory which has the same field content as the David-Distler-Kawai theory: it consists of a minimal matter scalar with background charge $Q$, dressed with an extra `Liouville' scalar. The construction is based on a generalization of the Kontsevich parametrization of the KP times achieved by introducing into it Miwa parameters which depend on the value of $Q$. Under the thus defined Kontsevich-Miwa transformation, the Virasoro constraints are proven to be equivalent to a master equation depending on the parameter $Q$. The master equation is further identified with a null-vector decoupling equation. We conjecture that $W^{(n)}$ constraints on the KP hierarchy are similarly related to a level-$n$ decoupling equation. We also consider the master equation for the $N$-reduced KP hierarchies. Several comments are made on a possible relation of the generalized master equation to {\it scaled} Kontsevich-type matrix integrals and on the form the equation takes in higher genera.Comment: 23pp (REVISED VERSION, 10 April 1992

Strings with Discrete Target Space

We investigate the field theory of strings having as a target space an arbitrary discrete one-dimensional manifold. The existence of the continuum limit is guaranteed if the target space is a Dynkin diagram of a simply laced Lie algebra or its affine extension. In this case the theory can be mapped onto the theory of strings embedded in the infinite discrete line $\Z$ which is the target space of the SOS model. On the regular lattice this mapping is known as Coulomb gas picture. ... Once the classical background is known, the amplitudes involving propagation of strings can be evaluated by perturbative expansion around the saddle point of the functional integral. For example, the partition function of the noninteracting closed string (toroidal world sheet) is the contribution of the gaussian fluctuations of the string field. The vertices in the corresponding Feynman diagram technique are constructed as the loop amplitudes in a random matrix model with suitably chosen potential.Comment: 65 pages (Sept. 91