Outlier-resistant estimators for Poisson sampling: a note

1998 ◽  
Vol 28 (5) ◽  
pp. 794-797 ◽  
Author(s):  
Michael S Williams ◽  
Hans T Schreuder

Poisson (3P) sampling is a commonly used method for generating estimates of timber volume. The usual estimator employed is the adjusted estimator, Y hata. The efficiency of this estimator can be greatly influenced by the presence of outliers. We formalize such a realistic situation for high-value timber estimation for which Y hata is inefficient. Here, yi approx beta xi for all but a few units in a population for which yi is large and xi very small. This situation can occur when estimating the net volume of high-value standing timber, such as that found in the Pacific Northwest region of the United States. A generalized regression estimator and an approximate Srivastava estimator are not affected by such data points. Simulations on a small population illustrate these ideas.

2020 ◽  
pp. 152483992094525
Author(s):  
Emily Kroshus ◽  
Deborah Bowen ◽  
Douglas Opel ◽  
Sara P. D. Chrisman ◽  
Frederick P. Rivara

Many families are concerned about their child’s risk of concussion, and some seek counsel from clinicians about whether or not to return to contact sports participation postinjury. The present study sought to identify factors that parents weight most heavily in forming their preferences regarding whether their child should return to contact sport after recovering from a concussion. Survey data were collected from 568 parents of youth football players (aged 7–14 years) in the Pacific Northwest region of the United States (73% response rate). Approximately two thirds (63%) of parents preferred that their child retire from football after one or two concussions. Multivariable linear regression indicated parents above the sample mean in terms of how strongly they valued football participation preferred their child stop after more concussions than parents below the sample mean (β = .44, standard error [SE] = 0.06, p < .001). Factors endorsed by the most parents as making them “much more likely” to want their child to stop playing football included the belief that their child will experience cognitive issues later in life as a result of concussions (65.0%) and that their child will get another concussion while playing football (43.5%). Within the context of a clinical visit postconcussion, physicians may need to help families clarify their values related to football participation and provide information about the potential outcomes of returning to contact sport. A formalized shared decision aid could help support consistent implementation of this potentially challenging conversation.


2006 ◽  
Vol 7 (5) ◽  
pp. 1164-1171 ◽  
Author(s):  
Anne W. Nolin ◽  
Christopher Daly

Abstract One of the most visible and widely felt impacts of climate warming is the change (mostly loss) of low-elevation snow cover in the midlatitudes. Snow cover that accumulates at temperatures close to the ice-water phase transition is at greater risk to climate warming than cold climate snowpacks because it affects both precipitation phase and ablation rates. This study maps areas in the Pacific Northwest region of the United States that are potentially at risk of converting from a snow-dominated to a rain-dominated winter precipitation regime, under a climate-warming scenario. A data-driven, climatological approach of snow cover classification is used to reveal these “at risk” snow zones and also to examine the relative frequency of warm winters for the region. For a rain versus snow temperature threshold of 0°C the at-risk snow class covers an area of about 9200 km2 in the Pacific Northwest region and represents approximately 6.5 km3 of water. Many areas of the Pacific Northwest would see an increase in the number of warm winters, but the impacts would likely be concentrated in the Cascade and Olympic Ranges. A number of lower-elevation ski areas could experience negative impacts because of the shift from winter snows to winter rains. The results of this study point to the potential for using existing datasets to better understand the potential impacts of climate warming.


2014 ◽  
pp. 1475-1495 ◽  
Author(s):  
Tami Echavarria Robinson

Continuing education for librarians and library staff is a need all libraries must consider for the effective professional development of their human resources and the functioning of their libraries. Similar concerns regarding the needs and barriers to obtaining ongoing continuing education are found across different types of libraries and in different regions of the country. Although studied separately and in different regions of the country, among concerns of library school media specialists documented in studies, results are similar to those revealed in a survey of Inland Northwest Library Council (INCOL) librarians in public, academic, and special libraries. Consortia offering continuing education are not well documented in the literature, but examples that exist reveal a feasible, collaborative, effective resource as a means to provide for these needs in member libraries. The history of these consortia is not only important as a means of documentation of their existence, but more so of their value and usefulness proven over a long time period. INCOL, in the Inland Northwest region of the Pacific Northwest of the United States, is a model of such a consortium that continues to be relevant after more than 30 years of offering ongoing continuing education to its constituency.


2012 ◽  
Vol 18 (8) ◽  
pp. 481-484 ◽  
Author(s):  
John D Scott ◽  
Kent T Unruh ◽  
Mary C Catlin ◽  
Joseph O Merrill ◽  
David J Tauben ◽  
...  

Plant Disease ◽  
2014 ◽  
Vol 98 (8) ◽  
pp. 1151-1151 ◽  
Author(s):  
S. T. Koike ◽  
M. P. Bolda ◽  
C. T. Bull

In February 2013 in coastal California (Santa Cruz County), plantings of red raspberry (Rubus idaeus var. strigosus) exhibited symptoms of a previously undocumented disease. Initial symptoms were small (less than 5 mm wide), angular, water-soaked lesions on leaf and petiole tissues of recently emerged foliage. Lesions were observable from both adaxial and abaxial leaf surfaces. As disease progressed, lesions enlarged and coalesced, resulting in significant dark brown to black blighting of the foliage. The foliage of severely affected plants was stunted and wilted. The disease affected 5 ha and incidence was approximately 30%. Cream-colored bacterial colonies were isolated from surface disinfested symptomatic tissue that was macerated and streaked onto King's medium B (KMB) and sucrose peptone agar (SPA). Fungi were not recovered from any tissue that was surface disinfested and placed into acidified potato dextrose agar. Four representative strains were fluorescent on KMB and gram-negative based on lysis by KOH. Strains were positive for levan formation, negative for oxidase and arginine dihydrolase, and did not cause soft rot on potato slices but induced a hypersensitive response in tobacco (Nicotiana tabacum L. cv. Samsun); strains thus belonged to Lelliot's LOPAT group 1, P. syringae (3). All four strains had identical DNA fragment-banding patterns generated by repetitive extragenic palindromic sequence (rep)-PCR using the BOXA1R primer (4). The pattern generated was different than all P. syringae pathovars in genomospecies 1 including P. syringae pv. syringae. According to multilocus sequence analysis conducted by previously described methods, the strains are most closely related to P. syringae pv. aceris and P. syringae pv. solidagae in genomospecies 1 (1). Potted raspberry plants were used to test four strains for pathogenicity. Inoculum was prepared by growing the bacteria on SPA for 48 h and suspending the bacteria in sterile distilled water (SDW) for a final concentration of approximately 107 CFU/ml. Suspensions were sprayed until runoff onto three replicate plants per strain. Control plants were sprayed with SDW until runoff. Plants were enclosed in plastic bags for 24 h and then maintained in a greenhouse (23 to 25°C). After 7 to 8 days, water soaked lesions developed on all inoculated plants; lesions later turned dark brown and appeared similar to symptoms observed in the field. Plants treated with water developed no symptoms. Bacteria re-isolated onto KMB from symptomatic tissues were fluorescent and appeared identical to the bacteria used to inoculate the plants; two selected re-isolated strains were identical to the original strains according to rep-PCR, fluorescence, and LOPAT reactions. The experiment was repeated and disease development and recovery of fluorescent strains on KMB was identical to the first experiment. To our knowledge, this is the first report of Pseudomonas blight of raspberry, caused by P. syringae, in California. Affected plants initially were stunted in growth but later in the summer exhibited no lasting effects from the disease. Pseudomonas blight has been reported in the Pacific Northwest region of the United States, the British Columbia region of Canada, and Serbia (2). References: (1) C. T. Bull et al. Phytopathology 101:847, 2011. (2) Z. Ivanovic et al. Eur. J. Plant Pathol. 134:191, 2012. (3) R. A. Lelliott. J. Appl. Bacteriol. 29:470, 1966. (4) A. S. A. Marques, et al. Genet. Mol. Biol. 31:106. 2008.


2020 ◽  
Vol 5 (1) ◽  
pp. 1-11
Author(s):  
Connie K. Y. Nguyen-Truong ◽  
Jacqueline Leung ◽  
Kapiolani Micky ◽  
Jennifer I. Nevers

Background: Despite mandates by the United States (U.S.) government to ensure the inclusion of women and minorities in federally funded research, communities of color continue to participate less frequently than non-Latinx Whites. There is limited research that examines maternal health outcomes and early childhood resources. Pacific Islanders (PI) have grown substantially in a county in the Pacific Northwest region of the U.S. (from 4,419 to 9,248, of which 52% are female). About 62.7% of PI women are not accessing prenatal care in the first trimester, and this is substantially higher than the national target of 22.1%. Researchers found that PI children are leaving school to take care of family obligations. The purpose of the educational innovative project, Building Safe Didactic Dialogues for Action model, was to respond to Micronesian Islanders (MI) parent leaders’ need to feel safe and to build a close kinship to encourage dialogue about difficult topics regarding access and utilization of early education systems and prenatal/perinatal health for community-driven model for action planning and solutions. Approach: Popular education tenets were used in the project to be culturally sensitive to the human experience. The MI community health worker outreached to MI parent leaders in an urban area in the Pacific Northwest region of the U.S. Eight partners participated in this project: parent leaders from the MI community-at-large, community partners from the MI Community organization, and academic nurse researchers. Didactic dialogues lasted two hours per session for four. Topics included: collaborative agreements, MI parent leaders’ identified needs and existing resources regarding preschool and immunization, parent–child relationship (stress and trauma, adverse childhood experiences), and MI experience regarding prenatal care access and postpartum depression. Group discussion on reflection was used to evaluate utility. Outcomes: Building Safe Didactic Dialogues for Action model was foundational via mobilizing community with MI, trust and rapport building, and engaging in a safe and courageous space for dialogues for action planning and solutions as community and academic partners as stakeholders. Conclusion: Many previously unspoken issues such as abuse, language, and cultural beliefs including barriers were openly shared among all partners. Dynamic thoughts towards identifying needs for change and then planning steps toward creating positive change created an atmosphere of empowerment for change.


2020 ◽  
Author(s):  
George Kral ◽  
Melodie Putnam ◽  
David Rupp

AbstractThe temperate maritime climate of the Pacific Northwest region of the United States supports the world’s tallest and most economically productive conifer forests. These forests are vital to local ecosystems and society, and climate perturbations are likely to adversely affect the services these forests provide. This study presents a simple, easily replicated methodology for assessing effects of climate change in these local forests, using species with differential climatic ranges as ecological barometers. A comparative analysis of warm-adapted and cool-adapted species co-occurring within a warming but otherwise climatically homogenous area near the southeast margin of the Pacific maritime forest reveals dramatic differences in tree health and mortality between these climatically differentiated species groups. Our results strongly suggest a rapid decline at the southeastern extent of the Pacific maritime temperate forest, and a need to immediately modify local land management practices to address this new reality.


2007 ◽  
Vol 135 (4) ◽  
pp. 1455-1473 ◽  
Author(s):  
Sébastien Dirren ◽  
Ryan D. Torn ◽  
Gregory J. Hakim

Abstract Ensemble Kalman filter (EnKF) data assimilation experiments are conducted on a limited-area domain over the Pacific Northwest region of the United States, using the Weather Research and Forecasting model. Idealized surface pressure, radiosoundings, and aircraft observations are assimilated every 6 h for a 7-day period in January 2004. The objectives here are to study the performance of the filter in constraining analysis errors with a relatively inhomogeneous, sparse-observation network and to explore the potential for such a network to serve as the basis for a real-time EnKF system dedicated to the Pacific Northwest region of the United States. When only a single observation type is assimilated, results show that the ensemble-mean analysis error and ensemble spread (standard deviation) are significantly reduced compared to a control ensemble without assimilation for both observed and unobserved variables. Analysis errors are smaller than background errors over nearly the entire domain when averaged over the 7-day period. Moreover, comparisons of background errors and observation increments at each assimilation step suggest that the flow-dependent filter corrections are accurate in both scale and amplitude. An illustrative example concerns a misspecified mesoscale 500-hPa short-wave trough moving along the British Columbia coast, which is corrected by surface pressure observations alone. The relative impact of each observation type upon different variables and vertical levels is also discussed.


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