Estimating the Multilevel Rasch Model: With the lme4 Package

Traditional Rasch estimation of the item and student parameters via marginal maximum likelihood, joint maximum likelihood or conditional maximum likelihood, assume individuals in clustered settings are uncorrelated and items within a test that share a grouping structure are also uncorrelated. These assumptions are often violated, particularly in educational testing situations, in which students are grouped into classrooms and many test items share a common grouping structure, such as a content strand or a reading passage. Consequently, one possible approach is to explicitly recognize the clustered nature of the data and directly incorporate random effects to account for the various dependencies. This article demonstrates how the multilevel Rasch model can be estimated using the functions in R for mixed-effects models with crossed or partially crossed random effects. We demonstrate how to model the following hierarchical data structures: a) individuals clustered in similar settings (e.g., classrooms, schools), b) items nested within a particular group (such as a content strand or a reading passage), and c) how to estimate a teacher x content strand interaction.

Equinox Studios: A Case Study

As a result of his own search for affordable, appropriately-sized workspace, sculptor Samuel Farrazaino became the accidental developer of artists’ studios. After subdividing leased spaces in two buildings in downtown and West Seattle, in 2006, he purchased an old World War II-era factory building in the industrial neighborhood of Georgetown on Seattle’s south side. Investing his own money and years of sweat equity in the face of financial and environmental challenges, Farrazaino and a team of like-minded artists built Equinox Studios. In the course of building a home for working artists, he created a thriving business enterprise and a mutually supportive community

An economic model of intransitivity : its application to persuasion

Honors thesi

Medieval rhetoric : its study and practice in northern Europe from 1050-1250

Dissertation (Ph.D.)--University of Kansas, Speech and Drama, 1973

Vladimir Ilyich Lenin’s theory of persuasion as a revolutionary strategy

Thesis (M.A.)--University of Kansas, Speech and Drama, 1969

Binary Star Systems in Planetary Nebulae and their Relationship to Stellar Evolution: Modeling Two New Binary Systems

The aim of this research was to learn more about close binary star systems and how they influence the formation of planetary nebulae at the end of a star’s life. These systems are produced by a common envelope phase where they share the same atmosphere and spiral closer together, causing stronger interactions between the stars. Properties of these systems can be used to better understand Type 1A supernovae, cataclysmic variable stars, and gravitational waves. There are 70 of these close binary star systems known, of which fewer than 20 have been modeled. This summer, models were generated for two of these systems, the central stars of Lo 16 and PHR 1510-6754. The parameters determined were masses, radii, temperatures, inclination, and separation of the stars. Both systems have an irradiation effect, with Lo 16 displaying a small eclipse. Possible solutions for both systems have been found, and at this time, the models indicate stellar parameters that are consistent with the expected ranges for these systems. Further work will aim for a more complete range of all possible parameters. Knowing the specific combination of parameters will lead to a better understanding of how these systems form, how they impact the shaping of the planetary nebula, and how they will continue to evolve in the future

Cover Density of a City Summer and Fall Bronzed Grackle Roost

Ames, Iowa, is one of the many Midwestern cities that have the dubious distinction of having a blackbird roost. During the summer and fall months thousands of birds each evening come to roost in the shade trees in· residential areas. Records kept in 1951 (Bliese, 1953a) indicated that roughly 74 per cent of the birds were bronzed grackles, Quiscalus quiscula. Regularly associated with them were about 22 per cent starlings, Sturnus vulgaris, 3 per cent cowbirds, Molothrus ater, and 1 per cent robins, Turdus migratorius. Observations from 1949 to 1952 also revealed that at times purple martins, Progne subis, red-wings, Agelaius phoeniceus, and English sparrows, Passer domesticus, were present also. One of the objectives of the investigation was to learn whether or not certain readily measurable features of the roost sites were correlated with the extent to which the birds used them. To that end records were kept of the degree of use accorded each tree in the roost area, as described in Bliese (1953 a & b). Degrees of use were: none, light, moderate, and heavy. Several physical measurements were made of the various trees, but only those dealing with cover density are discussed in this paper

Assessing Organizational Change in Multisector Community Health Alliances

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/110557/1/hesr12216-sup-0001-AuthorMatrix.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/110557/2/hesr12216.pd