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Physical Sciences and Mathematics Commons™
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- Bayesian (1)
- Bivariate (1)
- Bootstrap (1)
- Confirmatory Factor Analysis (1)
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- Gamma (1)
- Lognormal (1)
- Monte Carlo simulation (1)
- Negative binomial (1)
- Nondetects (1)
- Nonparametric methods (1)
- Online feedback (1)
- Orthogonal solution (1)
- Precision and stability of data model (1)
- Restricted inference problems (1)
- Sampling Design (SD) (1)
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- Spatial (1)
- Statistical computation (1)
- Statistical education study statistics (1)
- Statistical methodology (1)
- Variable selection (1)
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Articles 1 - 4 of 4
Full-Text Articles in Physical Sciences and Mathematics
Some Nonparametric Ordered Restricted Inference Problems In The Context Of A Statistical Education Study, Bradford M. Dykes
Some Nonparametric Ordered Restricted Inference Problems In The Context Of A Statistical Education Study, Bradford M. Dykes
Dissertations
Over the past 10 years, the Department of Statistics at Western Michigan University has developed a question generating system that can be used for creating multiple forms of exams, quizzes and homework for online and face-to-face use. This system can also be used to provide students with a form of instantaneous feedback. With the goal of analyzing how different levels of feedback in an online learning environment impacts students' performance on assignments, this study presents data collected on two semesters of students enrolled in three different meeting types (strictly online, typical face-to-face, and honors face-to-face) of an introductory Statistics course. …
Statistical Methodology For Data With Multiple Limits Of Detection, Robert M. Flikkema
Statistical Methodology For Data With Multiple Limits Of Detection, Robert M. Flikkema
Dissertations
Limitations of instruments used to collect continuous data sometimes lead to obtaining observations lower than a limit of detection. These observations are known as nondetects. They could be zeroes, or positive numbers, but they are too small to be recorded by a measuring device. Nondetects frequently occur in environmental data. Trace amounts of chemicals can exist in soil or groundwater and are undetectable by a machine reading. These observations pose a problem to researchers since the true values are unknown.
Simulations in the literature have led to inconsistent conclusions regarding what estimation technique to use with nondetect data when estimating …
Bivariate Negative Binomial Hurdle With Random Spatial Effects, Robert Mcnutt
Bivariate Negative Binomial Hurdle With Random Spatial Effects, Robert Mcnutt
Dissertations
Count data with excess zeros widely occur in ecology, epidemiology, marketing, and many other disciplines. Mixture distributions consisting of a point mass at zero and a separate discrete distribution are often employed in regression models to account for excessive zero observations in the data. While Poisson models are very popular for count data, Negative Binomial models provide greater flexibility due to their ability to account for overdispersion.
This research focuses on developing a method for analyzing bivariate count data with excess zeros collected over a lattice. A bivariate Zero-Inflated Negative Binomial Hurdle (ZINBH) regression model with spatial random effects is …
Empirical Evaluation Of Different Features Of Design In Confirmatory Factor Analysis, Deyab Almaleki
Empirical Evaluation Of Different Features Of Design In Confirmatory Factor Analysis, Deyab Almaleki
Dissertations
Factor analysis (FA) is the study of variance within a group. Within-subject variance (WSV) is affected by multiple features in a study context, such as: the study experimental design (ED) and sampling design (SD), thus anything that influences or changes variance may affect the conclusions related to FA.
The aim of this study was to provide empirical evaluation of the influence of different aspects of ED and SD on WSV in the context of FA in terms of model precision and model estimate stability. Four Monte Carlo population correlation matrices were hypothesized based on different communality magnitudes (high, moderate, low, …