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Animal movement has a fundamental impact on population and community structure and dynamics. Biased correlated random walks (BCRW) and step selection functions (SSF) are commonly used to study movements. Because no studies have contrasted the parameters and the statistical properties of their estimators for models constructed under these two Lagrangian approaches, it remains unclear whether or not they allow for similar inference. First, we used the Weak Law of Large Numbers to demonstrate that the log-likelihood function for estimating the parameters of BCRW models can be approximated by the log-likelihood of SSFs. Second, we illustrated the link between the two approaches by fitting BCRW with maximum likelihood and with SSF to simulated movement data in virtual environments and to the trajectory of bison (Bison bison L.) trails in natural landscapes. Using simulated and empirical data, we found that the parameters of a BCRW estimated directly from maximum likelihood and by fitting an SSF were remarkably similar. Movement analysis is increasingly used as a tool for understanding the influence of landscape properties on animal distribution. In the rapidly developing field of movement ecology, management and conservation biologists must decide which method they should implement to accurately assess the determinants of animal movement. We showed that BCRW and SSF can provide similar insights into the environmental features influencing animal movements. Both techniques have advantages. BCRW has already been extended to allow for multi-state modeling. Unlike BCRW, however, SSF can be estimated using most statistical packages, it can simultaneously evaluate habitat selection and movement biases, and can easily integrate a large number of movement taxes at multiple scales. SSF thus offers a simple, yet effective, statistical technique to identify movement taxis.

The path to successful source selection begins with Source Selection Step by Step: A Working Guide for Every Member of the Acquisition Team. Whether you are new to the acquisition team or an experienced practitioner looking to sharpen your skills, this comprehensive, highly readable handbook will guide you through the entire acquisition process, from designing an effective source selection plan, to preparing the solicitation, evaluating proposals, establishing a competitive range, and documenting the source selection decision.With clarity and frankness, Charles Solloway presents government sou

The following questionnaire/audit is designed to help management uncover possible deficiencies in their organization's hiring practices.

Identifying employee relations trouble spots that may contribute to unionization as well as to potential legal liability is a step every employer should take. The following audit questionnaire can help human resource professionals uncover possible deficiencies in their organization's labor and employment relations practices.

The article scrutinises the application process and its consequences in terms of educational inequalities in early selective grammar schools in Hungary. The focus is on the almost one-year-long process of preparation for the entrance exams to these grammar schools. Its main aim is to depict how the gradual nature of getting into secondary education intensifies social selection within the educational sector. The analysis is based upon the findings of a mixed method research, of which the results of the two waves of the survey and the consecutive interviews will be analysed. The article provides evidence of successful practices during the preparation process to these schools, as well as evidence of self-exclusion mechanisms for socially disadvantaged families. Overall, the results suggest that the most important selection factors are not the written or oral entrance exams themselves, but the decision to enter and remain in the preparation process, as well as the strategic decisions made by the parents during the preparation process.

AbstractWhile the dose–response relationship for the carcinogenic effects of arsenic exposure indicates nonlinearity with increases only above about 150 μg/L arsenic in drinking water, similar analyses of noncarcinogenic effects of arsenic exposure remain to be conducted. We present here an alternative analysis of data on a measure of aortic elasticity, a risk factor for hypertension, and its relationship to urinary arsenic levels. An occupational health study from Ankara, Turkey by Karakulak et al. compared urinary arsenic levels and a measure of aortic elasticity (specifically, aortic strain) in workers with a linear no‐threshold model. We have examined these data with three alternative models—a fitted step‐function, a stratified, and a weighted linear regression model. Discontinuity within the data revealed two subsets of data, one for workers with urinary arsenic levels ≤ 160 μg/L whose mean aortic strain level was 11.3% and one for workers with arsenic levels > 160 μg/L whose mean aortic stain level was 5.33 % (p < 0.0001). Several alternative models were examined that indicated the best model to be the threshold model with a threshold at a urinary arsenic level of 160 μg/L. Observation of a discontinuity in the data revealed their better fit to a threshold model (at a urinary arsenic level of 160 μg/L) than to a linear‐no threshold model. Examinations with alternative models are recommended for studies of arsenic and hypertension and possibly other noncarcinogenic effects.