Relationships among nutrients,chloride and biological indices in urban Maryland streams

Using a spatially extensive urban database constructed from the Maryland Biological Stream Survey (MBSS), we describe the relationships of nutrients in small-order streams to eight defined categories of percent catchment urbanization, correlations between chloride and conductivity in urban streams, and relationships between nutrients and chloride with two Maryland-specific indices of biotic integrity for benthic macroinvertebrates and fish assemblages. Stream nutrients become elevated with increasing percent catchment urbanization, followed by increases in all four measured nitrogen species and total phosphorus at catchment urbanization levels greater than 10%. There was a strong collinear relationship (r ² = 0.90) between chloride and conductivity (trimeans) across all eight urbanization classes, where Cl (mg/L) = −0.397 + 0.188*conductivity (μS/cm). Critical values for all water quality parameters with the two Maryland biological indices were derived using quantile regression, with significant regressions developed for 11 of 16 water quality parameters and the two biotic indices. For nitrate (NO₃-N), the critical thresholds between fair and poor stream quality for the two Maryland biological indices were 0.83 mg/L (benthic macroinvertebrate assemblages) and 0.86 mg/L (fish assemblages). Increasing stream nutrient and chloride levels, associated with widespread catchment urbanization intensity, now affect many small streams in Maryland, with implications for decreasing water quality in major tributaries and the Chesapeake Bay.     

Die Wirkung von Beratern

The theoretical basis behind consultancy does not match its importance to the economy. Although theory building research has been advanced since the 1990s, it still remains fragmentary. The impact of these consulting theories on practice has therefore been limited. This paper provides a contribution to this recent field of research. Based on the Social Systems Theory by Luhmann, a model outlining the impact of consultancy is presented. Three empirical cases outline the usefulness of the presented model in practice.     

Government Intervention in Public Sector Industrial Relations: Lessons from the Alberta Teachers’ Association

In the public sector, Canadian governments intervene frequently in labor disputes by suspending collective bargaining and curtailing legal strikes. Previous research has focused on the contours of government intervention, such as its overall effects on collective bargaining and strikes. The discussion highlights one actor, a government, restricting the behavior of another actor, a union, using legislation and policy making. As a result, we know less about more micro-level elements and implications of the process of government intervention. I address these themes using a detailed case study of the Alberta Teachers’ Association and the strikes it coordinated in 2002.

The Experience-Earnings Profile: Productivity-Augmenting or Purely Contractual? Evidence from the UK

We test the human capital interpretation of the experience-earnings profile. Does the upward sloping portion of the experience-earnings profile reflect on-the-job training which in turn causes the experience-productivity profile to slope upwards, or do purely contractual factors determine the nature of life-cycle earnings. Herein, we provide additional evidence on the relationship between productivity and earnings by examining earnings differentials in the UK academic labor market for economists. Using a test first suggested by Mincer, we find that the empirical results are consistent with human capital theory. We find that, although the positive relationship between earnings and experience persists when individual productivity measures are included in the salary equations for lecturers and senior lecturers, the positive relationship becomes statistically insignificant when the same productivity measures are included in the salary equations for professors. For lecturers and senior lecturers, the experience-salary profile properly reflects the structure of the national pay scale rather than variations in individual research productivity. At the professor level, where individual salaries are not determined by a pay scale, the data support the human capital explanation of the positive experience-earnings profile.

Reading your Counterpart: The Benefit of Emotion Recognition Accuracy for Effectiveness in Negotiation

Using meta-analysis, we find a consistent positive correlation between emotion recognition accuracy (ERA) and goal-oriented performance. However, this existing research relies primarily on subjective perceptions of performance. The current study tested the impact of ERA on objective performance in a mixed-motive buyer-seller negotiation exercise. Greater recognition of posed facial expressions predicted better objective outcomes for participants from Singapore playing the role of seller, both in terms of creating value and claiming a greater share for themselves. The present study is distinct from past research on the effects of individual differences on negotiation outcomes in that it uses a performance-based test rather than self-reported measure. These results add to evidence for the predictive validity of emotion recognition measures on practical outcomes.

Earnings Differentials of Seafarers

I investigate the earnings differentials among union and nonunion seafarers, across seafarer occupations, and with respective to other transport operatives. The empirical results suggest that the union and nonunion weekly earnings of captains/mates are comparable, and the union earnings gap for sailors/deckhands is positive. The union (nonunion) weekly earnings of captains/mates are 14.7 (30.5) percent greater than those of sailors/deckhands; the union weekly earnings of captains/mates (sailors/deckhands) are 12.6% greater (9.5% less) than those of truck drivers; and the nonunion weekly earnings of captains/mates (sailors/deckhands) are 33.0% greater (6.2% less) than those of truck drivers. The sailor/deckhand and truck driver earnings differentials are contrary to the general belief that the earnings of truck drivers are less than those of other operative occupations involved in transporting intermodal cargo.

Virtual Interpersonal Touch and Digital Chameleons

We studied the characteristics of hand touch with a mechanical device that approximated a handshake, and we then examined the effect of handshake mimicry on assessment of a partner. Two participants interacted with a force-feedback joystick that recorded each of their hand movements individually. The two participants then greeted one another by feeling the recording of the other person’s movements via the force-feedback device. For each dyad, one of the participants actually received his or her own virtual handshake back under the guise that it was the other person’s virtual handshake. Results demonstrated three significant findings. First, for any given participant, a metric that took into account position, angle, speed, and acceleration of the hand movements correlated highly within individuals across two handshakes. Second, across participants, these metrics demonstrated specific differences by gender. Finally, there was an interaction between gender and mimicry, such that male participants liked people who mimicked their handshakes more than female participants did. We discuss the implications of these findings and relate them to theories of social interaction.

Using age and spatial flow structures in the indirect estimation of migration streams

This article outlines a formal model-based approach for inferring interregional age-specific migration streams in settings where such data are incomplete, inadequate, or unavailable. The estimation approach relies heavily on log-linear models, using them to impose some of the regularities exhibited by past age and spatial structures or to combine and borrow information drawn from other sources. The approach is illustrated using data from the 1990 and 2000 U.S. and Mexico censuses.     

As low birth weight babies grow,can well-educated parents buffer this adverse factor? A research note

This research note combines two national Taiwanese data sets to investigate the relationships among low birth weight (LBW) babies, their parents' educational levels, and their future academic outcomes. We find that LBW is negatively correlated with the probability of such children attending college at age 18; however, when both parents are college or high school graduates, such negative effects may be partially offset. We also show that discrimination against daughters occurs, but only for daughters who were LBW babies. Moreover high parental education can buffer the LBW shock only among moderately LBW children (as compared with very LBW children) and full-term LBW children (as compared with preterm LBW children).     

Race,military service,and marital timing: Evidence from the NLSY-79

I use data from the 1979 National Longitudinal Study of Youth to examine the relationship between military service and marital timing for white men and black men during the 1980s. I use information about active-duty and reserve-duty service as well as veteran status to implement strong controls for selectivity. I find that active-duty military service increases the probability of first marriage for both whites and blacks. In part, this relationship is due to positive selectivity into the military and, for whites, to greater income and economic stability. Above and beyond the effects of selectivity, income, and economic stability, the effect of active-duty military service is particularly strong for black men.