Richard Anderson-Sprecher

University of Wyoming | UW · Department of Statistics

The automated techniques used to collect pavement conditions on county roads are relatively expensive for local agencies. This study evaluates the possibility of reducing the amount of pavement condition data collected in each survey to optimize the costs of data collection. This study applies multiple imputation analyses as an assistant tool to es...

Significance Coincident with the human colonization of the Western Hemisphere, dozens of genera of Pleistocene megafauna were lost to extinction. Following Martin, we argue that declines in the record of radiocarbon dates of extinct genera may be used as an independent means of detecting the first presence of humans in the New World. Our results, b...

Polar bears (Ursus maritimus) summer on the sea ice or, where it melts, on shore. Although the physiology of "ice" bears in summer is unknown, "shore" bears purportedly minimize energy losses by entering a hibernation-like state when deprived of food. Such a strategy could partially compensate for the loss of on-ice foraging opportunities caused by...

This paper presents a novel theoretical framework for swarms of agents. Before deploying a swarm for a task, it is advantageous to predict whether a desired percentage of the swarm will succeed. The authors present a framework that uses a small group of expendable “scout” agents to predict the success probability of the entire swarm, thereby preven...

This chapter presents a novel statistical framework for risk assessment of robotic swarm operations. This research has arisen from the crucial problem of predicting (before actual deployment) what portion of the swarm will succeed in accomplishing its mission. Our scouts framework uses a small group of expendable “scout” agents to predict the succe...

Earthquake swarms occur in many regions of the world. The study of earthquake swarms is very limited, and most contributions are descriptive. In this paper we propose use of a hidden Markov model to estimate the distribution of waiting times for swarm earthquakes and apply this approach to the largest earthquake swarm in the history of the Yellowst...

This paper presents a statistical approach named multivariate hidden Markov modeling (MHMM) and employs it to study the spatial and temporal distribution of earthquakes in the 1985 Yellowstone earthquake swarm. It also explores the potential of the approach for identifying fluid signals in the swarm. As far as the spatial distribution component is...

ABSTRACT Estimating abundance of carnivore populations is problematic because individuals typically are elusive, nocturnal, and dispersed across the landscape. Rare or endangered carnivore populations are even more difficult to estimate because of small sample sizes. Considering behavioral ecology of the target species can drastically improve surve...

This paper presents a novel theoretical framework for swarms of agents. Before deploying a swarm for a task, it is advantageous to predict whether a desired percentage of the swarm will succeed. The authors present a framework that uses a small group of expendable "scout" agents to predict the success probability of the entire swarm, thereby preven...

Social disorganization theory attempts to explain the relationships of community characteristics and patterns of illicit drug use, but methamphetamine poses a problem for this perspective. Methamphetamine use is prevalent in rural areas, where greater community social organization may contribute to its usage, a possibility examined here using data...

By comparing the isotopic composition of tissues deposited at different times, we can identify individuals that shift diets over time and individuals with constant diets. We define an individual as an isotopic specialist if tissues deposited at different times have similar isotopic composition. If tissues deposited at different times differ in isot...

The scenario addressed here is that of a swarm of agents (simulated robots) that needs to travel from an initial location to a goal location, while avoiding obstacles. Before deploying the entire swarm, it would be advantageous to have a certain level of confidence that a desired percentage of the swarm will be likely to succeed in getting to the g...

Understanding rates of isotopic incorporation and discrimination factors between tissues and diet is an important focus of ecologists seeking to use stable isotopes to track temporal changes in diet. We used a diet-shift experiment to measure differences among tissues in (13)C incorporation rates in house sparrows (Passer domesticus). We predicted...

Ecologists conduct isotopic incorporation experiments to determine the residence time of various stable isotopes in animal tissues. These experiments permit determining the time window through which isotopic ecologists perceive the course of diet changes, and therefore the scale of the inferences that we can make from isotopic data. Until recently,...

Low bit-rate speech codecs are important in many critical communication systems used by the military, police and fire departments, homeland security and other first responders. Such codecs offer low bandwidth, ease of encryption, and reasonable voice quality. Their increasing role in emergency communication scenarios requires them to function relia...

The performance of a naïve Bayes classifier is compared with a well-established statistical classification approach, linear discriminant analysis, by considering core and log data from marine–eolian sediments. The results indicate that both methods perform adequately, and the Gaussian naïve Bayes classifier provides estimates as good as those based...

Ultrasonic accelerated moisture conditioning (UAMC) has been demonstrated to be a quantitative analysis to evaluate the moisture sensitivity of a hot mix asphalt (HMA) mixture. Data from the UAMC test procedure was evaluated for repeatability and statistically compared to tensile strength test results after one and multiple cycles of freeze-thaw co...

We evaluate the performance of several estimators of animal location when data arise from radio telemetry studies. We assume that error-prone bearings are taken at regular time intervals from known locations, that observations may be frequent enough to introduce temporal dependencies, and that animals remain within well-defined home ranges. We simu...

1] The six longest records of stratospheric aerosol (in situ measurements at Laramie, Wyoming, lidar records at: Garmisch-Partenkirchen, Germany; Hampton, Virginia; Mauna Loa, Hawaii; São José dos Campos, Brazil, and SAGE II measurements) were investigated for trend by (1) comparing measurements in the 3 volcanically quiescent periods since 1970 us...

Modeling storm occurrences has become a vital part of hurricane prediction. In this paper, a method for simulating event occurrences using a simulated annealing algorithm is described. The method is illustrated using annual counts of hurricanes and of tropical storms in the Atlantic Ocean and Gulf of Mexico. Simulations closely match distributional...

We propose a new method for developing standard-weight (Ws) equations for use in the computation of relative weight (Wr) because the regression line–percentile (RLP) method often leads to length-related biases in Ws equations. We studied the structural properties of Ws equations developed by the RLP method through simulations, identified reasons fo...

The physical and chemical properties of aggregates used in the construction of asphalt pavements play a significant role in establishing the moisture sensitivity of the pavement. However, distinguishing the level of contribution of each property has been difficult due to the limitation on the number of variables that can be practically studied in a...

Junge's initial stratospheric aerosol measurements (1959-1960), at the end of a long volcanically quiescent period, and the long term stratospheric aerosol measurements beginning in the 1970s have been investigated for trends in non-volcanic stratospheric aerosol. These investigations have focused on the inter-volcanic "background" periods, which u...

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Neospora caninum infection is a common cause of bovine abortion. One method by which cattle can acquire infection is through ingestion of oocysts; however, this has not yet been proved to cause transplacental infection or abortion. In this study, 19 cows, pregnant between 70 and 176 days, were administered 1500 to 115,000 oocysts through an esophag...

We propose a new method for assessing length-related biases in standard weight (Ws) equations computed by the regression-line−percentile method. We evaluated the performance of the new method relative to two previous methods for assessing length-related biases using 15 data sets from which Ws equations have been computed. The new method detected po...

Temperature sensors were placed in the abdominal cavity, on the neck, and outside the dens of 5 hibernating black bears (Ursus americanus) during early winter and removed at the end of winter before emergence of bears from their dens. Bears did not arouse from torpor throughout the winter test period. Abdominal temperature remained within a 1.5°C t...

We previously reported that Neospora caninum can be induced to express BAGI, a bradyzoite antigen, within 3 days of culture under stress conditions. The main goals of the present experiment were to increase the expression of BAGI in vitro (in part by extending cultures for 9 days), to observe parasitophorous vacuoles at various points of stage diff...

Reduced agent-area treatment (RAAT) is a pest management strategy in which the rate of insecticide is reduced from traditional levels, and untreated swaths (refuges) are alternated with treated swaths. This approach is intended to achieve a more economically and environmentally sound pest management strategy compared to traditional blanket applicat...

To determine whether cows with evidence of previous infection with Neospora caninum were less likely to abort or give birth prematurely during an outbreak of neosporosis, compared with herdmates with evidence of primary infection. Cohort study. 208 pregnant beef cows. Aborted fetuses and calves born prematurely were examined during an outbreak of n...

This paper investigates the use of nonlinear regression to correct the inherent gain and phase mismatches between the in-phase (I) and quadrature (Q) branches of a quadrature receiver. The gain and phase errors are quite generally modeled by allowing frequencydependent variations for a particular receiver. Under modest assumptions, the system intri...

Serum samples from 70 (33 aborting and 37 non-aborting) dairy cows from a herd in California were analyzed for Neospora caninum antibodies in different laboratories by various serologic assays including enzyme-linked immunosorbent assay (ELISA) with recombinant antigens (Nc4.1 and Nc14.1), kinetic ELISA, whole tachyzoite lysate ELISA, immunostimula...

Identification of a definitive host for Neospora caninum has been inhibited by lack of an efficient method for producing bradyzoites, needed for oral infectivity trials. An improved protocol for producing bradyzoite-containing tissue cysts in mouse brains is described. Six variables, including mouse strain (Balb/C, CBA/Ca, and ICR), sex, N. caninum...

In many applications, bearings are measured to a moving object with the goal of estimating the object's course of movement. If movement is appropriately modeled as a smooth deterministic curve in the plane, then a cubic spline is a reasonable representation of the curve. Maximum likelihood estimators are presented for parameters of regression splin...

The sampling theory developed and described by Pierre Gy [1] is compared to design-based classical finite sampling methods for estimation of a ratio of random variables. For samples of materials which can be completely enumerated the methods are asymptotically equivalent. Gy extends the finite sampling methods to situations where complete enumerati...

Ignoring or inappropriately treating missing data can lead to inefficiency and biased estimation. Three classes of missing data are defined and an overview of various methods for accommodating missing data is presented. A model-based approach to missing data is advanced, and tools for finding maximum- likelihood estimates in this context-in particu...

First Page of the Article

The location of wildlife is frequently determined using telemetry data gathered at short intervals. If radio transmissions are reflected, as often occurs in mountainous regions, then existing location estimation techniques re unreliable. We explore the effects of gross observation errors upon current analyses and suggest an alternative analysis bas...

This is a brief communication about mucosal change in ileal urinary reservoirs, the earliest reported observations to date. Previous authors described early villous atrophy and crypt elongation, late panmucosal atrophy and metaplasia. Crypt cell proliferation should be a forerunner of these events and therefore warrants quantitative measurement. We...

Much of the confusion surrounding interpretation and application of the coefficient of determination, R , can be alleviated if it is defined explicitly as a comparison of a given model to the null model EY = β0. The model-comparison definition allows R to be easily generalized, and standard extensions such as coefficients of partial determination a...

Proper application of statistical principles at the onset of an environmental study can make the difference between an effective, efficient study and wasted resources. This review distills some of the thoughts current among environmental scientists from a variety of backgrounds and organizes them according to statistical principles. Collection and...

The location of wildlife is frequently determined from telemetry data. Current procedures may inadequately account for time-dependencies in the data and errors in the observations. We propose a nonlinear state-space model that addresses these two shortcomings. Let yt be a vector of angles measured between known antenna locations and unknown animal...