MULTISOURCE FEEDBACK LEADERSHIP RATINGS: ANALYZING FOR MEASUREMENT INVARIANCE AND COMPARING RATER GROUP IMPLICIT LEADERSHIP THEORIES

This research outlines a conceptual framework and data analysis process to examine multisource feedback (MSF) rater group differences from a leadership assessment survey, after testing the measures for equivalence. MSF gathers and compares ratings from supervisors, peer, followers and self and is the predominant leadership assessment tool in the United States. The results of MSF determine significant professional outcomes such as leadership development opportunities, promotions and compensation. An underlying belief behind the extensive use of MSF is that each rater group has a different set of implicit leadership theories (ILTs) they use when assessing the leader, and therefore each group is able to contribute unique insight. If this is true, research findings would find rater group consistency in leadership assessment outcomes, but they do not. A review of group comparison research reveals that most empirical MSF studies fail to perform preliminary data exploration, employ consistent models or adequately test for measurement equivalence (ME); yet industry standards strongly suggest exploratory methods whenever data sets undergo changes, and misspecified models cause biased results. Finally, ME testing is critical to ascertain if rater groups have similar conceptualizations of the factors and items in an MSF survey. If conceptual ME is not established, substantive group comparisons cannot be made. This study draws on the extant MSF, ILT and ME literature and analyzes rater group data from a large, application-based MSF leadership database. After exploring the data and running the requisite MI tests, I found that the measures upheld measurement invariance and were suitable for group comparison. Additional MI tests for substantive hypotheses support found that significant mean differences did exist among certain rater groups and dimensions, but only direct report and peer groups were consistently significantly different in all four dimensions (analytical, interpersonal, courageous and leadership effectiveness). Additionally, the interpersonal dimension was the most highly correlated with leadership effectiveness in all five rater groups. The overall findings of this study address the importance of MSF data exploration, offer alternative explanations to the disparate leadership MSF research findings to date and question the application use of MSF tools in their current form

Using Social Network Analysis to Explore Digital Student Interactions and Business Competency Learning in a Web-based Educational Platform:

Web 2.0 tools occupy a large part of our lives, and their use in the classroom offers instructors a unique opportunity to gather substantial information about individual and interactive student behaviors. The authors’ challenge is understanding the implications of this rich data source for assessing course efficacy and student learning, and applying these insights to further enhance the development of global business competencies. This paper reviews 311 student interactions as reflected in comments exchanged in a digital social learning community and, using social network analysis, discusses the potential to use these interactions to assess student critical thinking, communication, and collaborative feedback skills. The authors conclude with implications and recommendations for instructors who want to use Web 2.0 platforms and data to enhance their understanding of student and class digital interactions, and apply this information to course enhancement

Enhancing Teacher Credibility: What We Can Learn From the Justice and Leadership Literature

Enhanced perceptions of instructor credibility are related to positive outcomes in the classroom, including participation and learning (Chory, 2007; Frymier & Thompson, 1992; McCroskey & Teven, 1999; Myers, 2004; Teven & McCroskey, 1997). We contend that student perceptions of instructor credibility can be directly impacted by applying management research to classroom practices. In other words, actionable management research is useful in the classroom not just to share with students because it may make them better managers, but also to improve teaching practices and related outcomes. The present article explores this tenet, first discussing why we believe applied research findings can and should be transferred to the classroom and then using Implicit Leadership Theory (ILT) and organizational justice literature to demonstrate how these concepts can be generalized to the classroom environment to ultimately enhance instructor credibility

Phylogenetic relationships of African microhylid frogs inferred from DNA sequences of mitochondrial 12S and 16S rRNA genes

The phylogenetic relationships of microhylid frogs are poorly understood. The first molecular phylogeny for continental African microhylids is presented, including representatives of all subfamilies, six of the eight genera, and the enigmatic hemisotid Hemisus. Mitochondrial 12S and 16S rRNA sequence data were analysed using parsimony, likelihood and Bayesian methods. Analyses of the data are consistent with the monophyly of all sampled subfamilies and genera. Hemisus does not nest within either brevicipitines or non-brevicipitines. It is possibly the sister group to brevicipitines, in which case brevicipitines might not be microhylids. Phrynomantis and Hoplophryne potentially group with non-African, non-brevicipitine microhylids, in agreement with recent morphological and molecular data. Within brevicipitines, Breviceps is recovered as the sister group to a clade of Callulina+Spelaeophryne+Probreviceps. The relationships among the genera within this latter clade are unclear, being sensitive to the method of analysis. Optimal trees suggest the Probreviceps macrodactylus subspecies complex might be paraphyletic with respect to P. uluguruensis, corroborating preliminary morphological studies indicating that P. m. rungwensis may be a distinct species. P. m. loveridgei may be paraphyletic with respect to P. m. macrodactylus, though this is not strongly supported. Some biogeographic hypotheses are examined in light of these findings

Sensitivity and Specificity of Multiple Kato-Katz Thick Smears and a Circulating Cathodic Antigen Test for Schistosoma mansoni Diagnosis Pre- and Post-repeated-Praziquantel Treatment

Two Kato-Katz thick smears (Kato-Katzs) from a single stool are currently recommended for diagnosing Schistosoma mansoni infections to map areas for intervention. This ‘gold standard’ has low sensitivity at low infection intensities. The urine point-of-care circulating cathodic antigen test (POC-CCA) is potentially more sensitive but how accurately they detect S. mansoni after repeated praziquantel treatments, their suitability for measuring drug efficacy and their correlation with egg counts remain to be fully understood. We compared the accuracies of one to six Kato-Katzs and one POC-CCA for the diagnosis of S. mansoni in primary-school children who have received zero to ten praziquantel treatments. We determined the impact each diagnostic approach may have on monitoring and evaluation (M&E) and drug-efficacy findings

Functional Remineralization of Dentin Lesions Using Polymer-Induced Liquid-Precursor Process

It was hypothesized that applying the polymer-induced liquid-precursor (PILP) system to artificial lesions would result in time-dependent functional remineralization of carious dentin lesions that restores the mechanical properties of demineralized dentin matrix. 140 µm deep artificial caries lesions were remineralized via the PILP process for 7–28 days at 37°C to determine temporal remineralization characteristics. Poly-L-aspartic acid (27 KDa) was used as the polymeric process-directing agent and was added to the remineralization solution at a calcium-to-phosphate ratio of 2.14 (mol/mol). Nanomechanical properties of hydrated artificial lesions had a low reduced elastic modulus (ER = 0.2 GPa) region extending about 70 μm into the lesion, with a sloped region to about 140 μm where values reached normal dentin (18–20 GPa). After 7 days specimens recovered mechanical properties in the sloped region by 51% compared to the artificial lesion. Between 7–14 days, recovery of the outer portion of the lesion continued to a level of about 10 GPa with 74% improvement. 28 days of PILP mineralization resulted in 91% improvement of ER compared to the artificial lesion. These differences were statistically significant as determined from change-point diagrams. Mineral profiles determined by micro x-ray computed tomography were shallower than those determined by nanoindentation, and showed similar changes over time, but full mineral recovery occurred after 14 days in both the outer and sloped portions of the lesion. Scanning electron microscopy and energy dispersive x-ray analysis showed similar morphologies that were distinct from normal dentin with a clear line of demarcation between the outer and sloped portions of the lesion. Transmission electron microscopy and selected area electron diffraction showed that the starting lesions contained some residual mineral in the outer portions, which exhibited poor crystallinity. During remineralization, intrafibrillar mineral increased and crystallinity improved with intrafibrillar mineral exhibiting the orientation found in normal dentin or bone

Localizing Sagittarius A* and M87 on Microarcsecond Scales with Millimeter VLBI

With the advent of the Event Horizon Telescope (EHT), a millimeter/sub-millimeter very-long baseline interferometer (VLBI), it has become possible to image a handful of black holes with sub-horizon resolutions. However, these images do not translate into microarcsecond absolute positions due to the lack of absolute phase information when an external phase reference is not used. Due to the short atmospheric coherence time at these wavelengths, nodding between the source and phase reference is impractical. However, here we suggest an alternative scheme which makes use of the fact that many of the VLBI stations within the EHT are arrays in their own right. With this we show that it should be possible to absolutely position the supermassive black holes at the centers of the Milky Way (Sgr A*) and M87 relative to nearby objects with precisions of roughly 1 microarcsecond. This is sufficient to detect the perturbations to Sgr A*'s position resulting from interactions with the stars and stellar-mass black holes in the Galactic cusp on year timescales, and severely constrain the astrophysically relevant parameter space for an orbiting intermediate mass black hole, implicated in some mechanisms for producing the young massive stars in the Galactic center. For M87, it allows the registering of millimeter images, in which the black hole may be identified by its silhouette against nearby emission, and existing larger scale radio images, eliminating present ambiguities in the nature of the radio core and inclination, opening angle, and source of the radio jet.Comment: 18 pages, 4 figures, Accepted for publication in Ap

Mass Stranding of Marine Birds Caused by a Surfactant-Producing Red Tide

In November-December 2007 a widespread seabird mortality event occurred in Monterey Bay, California, USA, coincident with a massive red tide caused by the dinoflagellate Akashiwo sanguinea. Affected birds had a slimy yellow-green material on their feathers, which were saturated with water, and they were severely hypothermic. We determined that foam containing surfactant-like proteins, derived from organic matter of the red tide, coated their feathers and neutralized natural water repellency and insulation. No evidence of exposure to petroleum or other oils or biotoxins were found. This is the first documented case of its kind, but previous similar events may have gone undetected. The frequency and amplitude of red tides have increased in Monterey Bay since 2004, suggesting that impacts on wintering marine birds may continue or increase