929 research outputs found
Analyzing Repeated Measures Marginal Models on Sample Surveys with Resampling Methods
Packaged statistical software for analyzing categorical, repeated measures marginal models on sample survey data with binary covariates does not appear to be available. Consequently, this report describes a customized SAS program which accomplishes such an analysis on survey data with jackknifed replicate weights for which the primary sampling unit information has been suppressed for respondent confidentiality. First, the program employs the Macro Language and the Output Delivery System (ODS) to estimate the means and covariances of indicator variables for the response variables, taking the design into account. Then, it uses PROC CATMOD and ODS, ignoring the survey design, to obtain the design matrix and hypothesis test specifications. Finally, it enters these results into another run of CATMOD, which performs automated direct input of the survey design specifications and accomplishes the appropriate analysis. This customized SAS program can be employed, with minor editing, to analyze general categorical, repeated measures marginal models on sample surveys with replicate weights. Finally, the results of our analysis accounting for the survey design are compared to the results of two alternate analyses of the same data. This comparison confirms that such alternate analyses, which do not properly account for the design, do not produce useful results.
Analyzing Repeated Measures Marginal Models on Sample Surveys with Resampling Methods
Packaged statistical software for analyzing categorical, repeated measures marginal models on sample survey data with binary covariates does not appear to be available. Consequently, this report describes a customized SAS program which accomplishes such an analysis on survey data with jackknifed replicate weights for which the primary sampling unit information has been suppressed for respondent confidentiality. First, the program employs the Macro Language and the Output Delivery System (ODS) to estimate the means and covariances of indicator variables for the response variables, taking the design into account. Then, it uses PROC CATMOD and ODS, ignoring the survey design, to obtain the design matrix and hypothesis test specifications. Finally, it enters these results into another run of CATMOD, which performs automated direct input of the survey design specifications and accomplishes the appropriate analysis. This customized SAS program can be employed, with minor editing, to analyze general categorical, repeated measures marginal models on sample surveys with replicate weights. Finally, the results of our analysis accounting for the survey design are compared to the results of two alternate analyses of the same data. This comparison confirms that such alternate analyses, which do not properly account for the design, do not produce useful results
Modeling self-organization of communication and topology in social networks
This paper introduces a model of self-organization between communication and
topology in social networks, with a feedback between different communication
habits and the topology. To study this feedback, we let agents communicate to
build a perception of a network and use this information to create strategic
links. We observe a narrow distribution of links when the communication is low
and a system with a broad distribution of links when the communication is high.
We also analyze the outcome of chatting, cheating, and lying, as strategies to
get better access to information in the network. Chatting, although only
adopted by a few agents, gives a global gain in the system. Contrary, a global
loss is inevitable in a system with too many liarsComment: 6 pages 7 figures, Java simulation available at
http://cmol.nbi.dk/models/inforew/inforew.htm
Advance Care Planning Within Individualized Care Plans: A Component of Emergency Preparedness
Federally-legislated Medicaid requirements for recipients with intellectual and/or developmental disabilities (IDD) to have a person-centered plan (PCP) do not specifically require that advanced care plans (ACP) be a component of the plan. However, coronavirus disease 2019 (COVID-19) has provided a salient reminder of the importance of incorporating ACP within the PCP for people who have IDD. As demonstrated by situations arising from COVID-19, emergencies and crises can dramatically alter access to care for people with IDD. This paper synthesizes results from an environmental scan related to ACP for adults with IDD. Findings suggest that the use of ACP, particularly when such planning processes result in the delineation of roles and documentation of preferences, can be helpful in mitigating the impact of these crisis situations on the person with IDD and their caregivers
Synthesis, Structure, and Ferromagnetism of a New Oxygen Defect Pyrochlore System Lu2V2O_{7-x} (x = 0.40-0.65)
A new fcc oxygen defect pyrochlore structure system Lu2V2O_{7-x} with x =
0.40 to 0.65 was synthesized from the known fcc ferromagnetic semiconductor
pyrochlore compound Lu2V2O7 which can be written as Lu2V2O6O' with two
inequivalent oxygen sites O and O'. Rietveld x-ray diffraction refinements
showed significant Lu-V antisite disorder for x >= 0.5. The lattice parameter
versus x (including x = 0) shows a distinct maximum at x ~ 0.4. We propose that
these observations can be explained if the oxygen defects are on the O'
sublattice of the structure. The magnetic susceptibility versus temperature
exhibits Curie-Weiss behavior above 150 K for all x, with a Curie constant C
that increases with x as expected in an ionic model. However, the magnetization
measurements also show that the (ferromagnetic) Weiss temperature theta and the
ferromagnetic ordering temperature T_C both strongly decrease with increasing x
instead of increasing as expected from C(x). The T_C decreases from 73 K for x
= 0 to 21 K for x = 0.65. Furthermore, the saturation moment at a field of 5.5
T at 5 K is nearly independent of x, with the value expected for a fixed spin
1/2 per V. The latter three observations suggest that Lu2V2O_{7-x} may contain
localized spin 1/2 vanadium moments in a metallic background that is induced by
oxygen defect doping, instead of being a semiconductor as suggested by the C(x)
dependence.Comment: 9 pages including 7 figures, 3 table
The diplomat's dilemma: Maximal power for minimal effort in social networks
Closeness is a global measure of centrality in networks, and a proxy for how
influential actors are in social networks. In most network models, and many
empirical networks, closeness is strongly correlated with degree. However, in
social networks there is a cost of maintaining social ties. This leads to a
situation (that can occur in the professional social networks of executives,
lobbyists, diplomats and so on) where agents have the conflicting objectives of
aiming for centrality while simultaneously keeping the degree low. We
investigate this situation in an adaptive network-evolution model where agents
optimize their positions in the network following individual strategies, and
using only local information. The strategies are also optimized, based on the
success of the agent and its neighbors. We measure and describe the time
evolution of the network and the agents' strategies.Comment: Submitted to Adaptive Networks: Theory, Models and Applications, to
be published from Springe
Parties, promiscuity and politicisation: business-political networks in Poland
Research on post-communist political economy has begun to focus on the interface between business and politics. It is widely agreed that informal networks rather than business associations dominate this interface, but there has been very little systematic research in this area. The literature tends to assume that a politicised economy entails business-political networks that are structured by parties. Theoretically, this article distinguishes politicisation from party politicisation and argues that the two are unlikely to be found together in a post-communist context. Empirically, elite survey data and qualitative interviews are used to explore networks of businesspeople and politicians in Poland. Substantial evidence is found against the popular idea that Polish politicians have business clienteles clearly separated from each other according to party loyalties. Instead, it is argued that these politicians and businesspeople are promiscuous. Since there seems to be little that is unusual about the Polish case, this conclusion has theoretical, methodological, substantive and policy implications for other post-communist countries
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