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Physical Sciences and Mathematics Commons™

Open Access. Powered by Scholars. Published by Universities.®

Statistics and Probability

Utah State University

2012

Articles 1 - 6 of 6

Full-Text Articles in Physical Sciences and Mathematics

Visual Data Mining Techniques For Functional Actigraphy Data: An Object-Oriented Approach In R, Abbass Sharif Dec 2012

Visual Data Mining Techniques For Functional Actigraphy Data: An Object-Oriented Approach In R, Abbass Sharif

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Actigraphy, a technology for measuring a subject's overall activity level almost continuously over time, has gained a lot of momentum over the last few years. An actigraph, a watch-like device that can be attached to the wrist or ankle of a subject, uses an accelerometer to measure human movement every minute or even every 15 seconds. Actigraphy data is often treated as functional data. In this dissertation, we discuss what has been done regarding the visualization of actigraphy data, and then we will explain the three main goals we achieved: (i) develop new multivariate visualization techniques for actigraphy data; (ii) …

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Assessing Changes In The Abundance Of The Continental Population Of Scaup Using A Hierarchical Spatio-Temporal Model, Beth E. Ross May 2012

Assessing Changes In The Abundance Of The Continental Population Of Scaup Using A Hierarchical Spatio-Temporal Model, Beth E. Ross

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

In ecological studies, the goal is often to describe and gain further insight into ecological processes underlying the data collected during observational studies. Because of the nature of observational data, it can often be difficult to separate the variation in the data from the underlying process or 'state dynamics.' In order to better address this issue, it is becoming increasingly common for researchers to use hierarchical models. Hierarchical spatial, temporal, and spatio-temporal models allow for the simultaneous modeling of both first and second order processes, thus accounting for underlying autocorrelation in the system while still providing insight into overall spatial …

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Interactive Random Forests Plots, Anna T. Quach May 2012

Interactive Random Forests Plots, Anna T. Quach

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Random Forests is a useful data mining tool that is quite popular in finding variable importance. However, many people don’t make use of the Random Forests results in interactive graphs. Partly, this is because software packages that can do interactive graphs can’t handle large data sets and those that use Random Forests have large data sets or many variables. A new software package in R, known as iPlots eXtreme, that is still in development makes it simple to explore large data sets interactively. I have created a function, called irfplot (interactive random forests plot) that specifically uses Random Forests to …

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Simulating Loan Repayment By The Sinking Fund Method (Sinking Fund Governed By A Sequence Of Interest Rates), Placede Judicaelle Gangnang Fosso May 2012

Simulating Loan Repayment By The Sinking Fund Method (Sinking Fund Governed By A Sequence Of Interest Rates), Placede Judicaelle Gangnang Fosso

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

The sinking fund method is a way to repay a loan where the borrower pays the amount of interest accrued by the principal at the end of each time period and puts a certain amount in a sinking fund in order to repay the principal at the end of the loan. Usually, we assume that the interest rate on the sinking fund is the same during the entire time of the loan. In the study, we will depart from the usual assumptions and will look at different scenarios, including when changes of the interest rate on the sinking fund follows …

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Ignoring The Spatial Context In Intro Statistics Classes - And Some Simple Graphical Remedies, Nathan Voge May 2012

Ignoring The Spatial Context In Intro Statistics Classes - And Some Simple Graphical Remedies, Nathan Voge

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Statistical data often have a spatial (geographic) context, be it countries of the world, states in the US, counties within a state, cities across the globe, or locations where measurements have been taken. However, most introductory statistics books do not even suggest that such data often are not independent from location, but rather are eected by some spatial association. Remedies are simple: Display data via various map views and brie y discuss which additional information can be extracted from such a graphical representation. In this report, we will visit a variety of popular introductory statistics textbooks and show how some …

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Robust Computational Tools For Multiple Testing With Genetic Association Studies, William L. Welbourn Jr. May 2012

Robust Computational Tools For Multiple Testing With Genetic Association Studies, William L. Welbourn Jr.

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The mapping of the human genome and the completion of the Human HapMap project over the past decade have significantly altered how research is conducted with respect to the genetic epidemiology of human disease. Study designs and analytic approaches have evolved rapidly from investigations involving relatively few targeted candidate genes to hypothesis-free genome-wide association studies, where thousands – and now even millions – of single molecular mutations are simultaneously analyzed to identify regions of the genome that may influence disease. As laboratory techniques continue to improve and costs decrease, the volume of genetic data will inexorably rise, and robust tools …

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