Predicting Large Population Data Cumulative Match Characteristic Performance from Small Population Data

2003 ◽  
pp. 821-829 ◽  
Author(s):  
Amos Y. Johnson ◽  
Jie Sun ◽  
Aaron F. Bobick
Keyword(s):  
Large Population ◽  
Population Data ◽  
Small Population

scholarly journals A Retrospective Experience of Helicobacter pylori Histology in a Large Sample of Subjects in Northern Italy

Life ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 650
Author(s):  
Davide Giuseppe Ribaldone ◽  
Carlo Zurlo ◽  
Sharmila Fagoonee ◽  
Chiara Rosso ◽  
Angelo Armandi ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Large Population ◽  
Population Data ◽  
Signet Ring Cell ◽  
Current Data ◽  
Low Grade ◽  
Gastric Cardia Adenocarcinoma ◽  
Significant Difference ◽  
H Pylori ◽  
The Impact

Updated data about the prevalence of Helicobacter pylori (H. pylori) and its correlation with histological results are scarce. The aim of our study was to provide current data on the impact of H. pylori in a third-level endoscopy service. We performed a large, retrospective study analyzing the results of all histological samples of gastroscopy from the year 2019. In total, 1512 subjects were included. The prevalence of H. pylori was 16.8%. A significant difference between the prevalence in subjects born in Italy and those from eastern Europe, south America, or Africa was found (p < 0.0001, p = 0.006, and p = 0.0006, respectively). An association was found between H. pylori and active superficial gastritis (p < 0.0001). Current H. pylori and/or a previous finding of H. pylori was related to antral atrophy (p < 0.0001). Fifteen patients had low-grade dysplasia. There were no statistically significant associations with current or past H. pylori infection. One patient presented gastric cardia adenocarcinoma with regular gastric mucosa. One patient, H. pylori positive, was diagnosed with gastric signet ring cell adenocarcinoma in a setting of diffuse atrophy, without metaplasia.. Our study provides updated, solid (biopsy diagnosis and large population) data on the prevalence of H. pylori infection in a representative region of southern Europe.

Multilevel Regression and Poststratification Versus Survey Sample Weighting for Estimating Population Quantities in Large Population Health Studies

2020 ◽  
Vol 189 (7) ◽  
pp. 717-725 ◽  
Author(s):  
Marnie Downes ◽  
John B Carlin
Keyword(s):  
Population Health ◽  
Large Scale ◽  
Census Data ◽  
Large Population ◽  
Population Data ◽  
Superior Performance ◽  
Population Parameter ◽  
Multilevel Regression ◽  
Sample Weighting ◽  
Survey Weighting

Abstract Multilevel regression and poststratification (MRP) is a model-based approach for estimating a population parameter of interest, generally from large-scale surveys. It has been shown to be effective in highly selected samples, which is particularly relevant to investigators of large-scale population health and epidemiologic surveys facing increasing difficulties in recruiting representative samples of participants. We aimed to further examine the accuracy and precision of MRP in a context where census data provided reasonable proxies for true population quantities of interest. We considered 2 outcomes from the baseline wave of the Ten to Men study (Australia, 2013–2014) and obtained relevant population data from the 2011 Australian Census. MRP was found to achieve generally superior performance relative to conventional survey weighting methods for the population as a whole and for population subsets of varying sizes. MRP resulted in less variability among estimates across population subsets relative to sample weighting, and there was some evidence of small gains in precision when using MRP, particularly for smaller population subsets. These findings offer further support for MRP as a promising analytical approach for addressing participation bias in the estimation of population descriptive quantities from large-scale health surveys and cohort studies.

scholarly journals PENGARUH PELATIHAN DAN LINGKUNGAN ORGANISASI TERHADAP KOMPETENSI SERTA DAMPAKNYA TERHADAP KINERJA PENYULUH PERTANIAN (Studi Pada Dinas Pertanian Dan Peternakan Daerah Provinsi Sulawesi Utara)

2019 ◽  
Vol 15 (3) ◽  
pp. 541
Author(s):  
Moch. Toha Khuseno
Keyword(s):  
Statistical Analysis ◽  
Animal Husbandry ◽  
Population Data ◽  
Agricultural Extension ◽  
Small Population ◽  
Organizational Environment ◽  
The North ◽  
North Sulawesi ◽  
Collection Methods ◽  
Descriptive Statistical Analysis

This study aims to determine the effect of training on Agricultural Extension competencies; know the effect of the organization's environment on Agricultural Extension competencies; know the effect of training on the performance of Agricultural Extension Workers; know the effect of the organizational environment on the performance of Agricultural Extension Workers; know the training factors and organizational environment on the performance of Agricultural Extension Workers through work competence as an intervening variable. This research was carried out using the exploratory method with a quantitative approach with the research location at the North Sulawesi Provincial Agriculture and Animal Husbandry Department. The number of samples is equal to the total population of 18 people given the small population. Data collection methods used are descriptive statistical analysis and inferential statistical analysis using path analysis with t-test as hypothesis testing. The results showed that training for Agricultural Extension Workers had a significant effect on work competence; the organizational environment also significantly influences the work competency of Agricultural Extension Workers; work Competence has a significant effect on the performance of Agricultural Extension Workers; Training also has a significant effect on the performance of Agricultural Extension Workers; the organizational environment has a positive and significant effect on the performance of agricultural instructors; training and Organizational Environment have a significant effect on the performance of Agricultural Extension Workers through their Work Competencies. There is an increase in the direct influence and indirect effect of each variable. *eprm*

scholarly journals Choosing Mutation and Crossover Ratios for Genetic Algorithms—A Review with a New Dynamic Approach

Information ◽  
2019 ◽  
Vol 10 (12) ◽  
pp. 390 ◽  
Author(s):  
Ahmad Hassanat ◽  
Khalid Almohammadi ◽  
Esra’a Alkafaween ◽  
Eman Abunawas ◽  
Awni Hammouri ◽  
...  
Keyword(s):  
Population Size ◽  
Optimization Problems ◽  
Large Population ◽  
Small Population ◽  
Mutation Rates ◽  
Mutation Operators ◽  
Tuning Methods ◽  
Two Parameters ◽  
The Impact ◽  
Crossover And Mutation

Genetic algorithm (GA) is an artificial intelligence search method that uses the process of evolution and natural selection theory and is under the umbrella of evolutionary computing algorithm. It is an efficient tool for solving optimization problems. Integration among (GA) parameters is vital for successful (GA) search. Such parameters include mutation and crossover rates in addition to population that are important issues in (GA). However, each operator of GA has a special and different influence. The impact of these factors is influenced by their probabilities; it is difficult to predefine specific ratios for each parameter, particularly, mutation and crossover operators. This paper reviews various methods for choosing mutation and crossover ratios in GAs. Next, we define new deterministic control approaches for crossover and mutation rates, namely Dynamic Decreasing of high mutation ratio/dynamic increasing of low crossover ratio (DHM/ILC), and Dynamic Increasing of Low Mutation/Dynamic Decreasing of High Crossover (ILM/DHC). The dynamic nature of the proposed methods allows the ratios of both crossover and mutation operators to be changed linearly during the search progress, where (DHM/ILC) starts with 100% ratio for mutations, and 0% for crossovers. Both mutation and crossover ratios start to decrease and increase, respectively. By the end of the search process, the ratios will be 0% for mutations and 100% for crossovers. (ILM/DHC) worked the same but the other way around. The proposed approach was compared with two parameters tuning methods (predefined), namely fifty-fifty crossover/mutation ratios, and the most common approach that uses static ratios such as (0.03) mutation rates and (0.9) crossover rates. The experiments were conducted on ten Traveling Salesman Problems (TSP). The experiments showed the effectiveness of the proposed (DHM/ILC) when dealing with small population size, while the proposed (ILM/DHC) was found to be more effective when using large population size. In fact, both proposed dynamic methods outperformed the predefined methods compared in most cases tested.

scholarly journals Nutritional status of adolescent girls in Bangladesh: findings of a community based survey

2016 ◽  
Vol 6 (1) ◽  
pp. 3-7 ◽  
Author(s):  
Kabir Hossen ◽  
Fazlur Rahman ◽  
Saidur Rahman Mashreky
Keyword(s):  
Nutritional Status ◽  
Adolescent Girls ◽  
Large Population ◽  
Population Data ◽  
Health Care Facilities ◽  
Cross Sectional Survey ◽  
Community Based ◽  
Cross Sectional ◽  
Household Level ◽  
Under Nutrition

Poverty, large population, socio- economic inequalities and inadequate access to proper health care facilities are the key causes of under nutrition in Bangladesh. Adolescents are the most vulnerable group for under nutrition and having great consequence as they will be parent in future. Studies on nutritional status of adolescent girls are fewer in number and have great effect for intervention. The objective of this study was to assess the nutritional status and predisposing factors of under nutrition among the adolescent girls in Bangladesh. A community-based cross-sectional survey was carried out from July to December 2013. Adolescent girls were the study population. Data was collected by face to face interview at household level. According to BMI category (kg/m2) the prevalence of under-weight (BMI<18.5) was found 65.9% and as per Gomez Classification (Weight for age), the prevalence of malnutrition was 48.2% (mild), 23.5% (moderate) and 2.8% (severe) categories and finally, as per Water Low Classification wasting found 16.6% (mild), 3.5%(moderate) and 0.2% severe categories. On the other hand, stunting found 39.6 % (mild), 9.2% (moderate) and 2.3% (severe) categories. Prevalence of under nutrition was found much higher (82.3%) among younger age group (?12 years). Higher prevalence of under-nutrition also found among the functionally illiterate adolescent girls, it was 75.8% and 51.3% among illiterate and literate group respectively. In both of the cases difference was statistically significant (p<0.001). The prevalence of illness found higher among under-weight adolescent girls in last two weeks compare to healthy adolescent girls both in rural and urban settings. This difference also found statistically significant (p<0.001). Under nourishment found higher among younger and low literate girls. Prevalence of other symptoms is also found higher among them.South East Asia Journal of Public Health Vol.6(1) 2016: 3-7

Anisakine Nematodes in Fresh Commercial Fish From Waters Along the Washington, Oregon and California Coasts

1979 ◽  
Vol 42 (5) ◽  
pp. 380-384 ◽  
Author(s):  
BETTY JUNE MYERS
Keyword(s):  
Definitive Host ◽  
Lower Incidence ◽  
Large Population ◽  
Small Population ◽  
Marine Fisheries ◽  
Commercial Fish ◽  
Fresh Fish ◽  
Fish Hosts

Two thousand and seventy four fresh fish representing 24 genera and 43 species were purchased from commercial marine fisheries in Washington, Oregon and California. They were examined for anisakine nematodes by dissection, candling or digestion of the muscle and elution of the viscera. Thirty thousand and thirty-two anisakine nematodes were recovered from the fish examined; however, no anisakine nematodes were recovered from the shellfish examined. Both Anisakis sp. and Phocanema sp., which are considered pathogens for human consumers of raw or semiraw fish, were encountered. Of the anisakines. Anisakis sp. larvae were found in a greater number of the fish hosts examined than Phocanema sp. larvae, which were found in fewer fish hosts and at lower incidence. The higher incidence of Anisakis sp. larvae was probably due to the large population of whales, the host in which this species reaches maturity. The lower incidence of Phocanema sp. larvae is a reflection of the small population of seals, the definitive host for this species.

scholarly journals Recovery within a population of the Critically Endangered citron-crested cockatoo Cacatua sulphurea citrinocristata in Indonesia after 10 years of international trade control

Oryx ◽  
2006 ◽  
Vol 40 (2) ◽  
pp. 161-167 ◽  
Author(s):  
Alexis J. Cahill ◽  
Jonathan S. Walker ◽  
Stuart J. Marsden
Keyword(s):  
International Trade ◽  
Forest Cover ◽  
Population Data ◽  
Small Population ◽  
Forest Patches ◽  
Field Methods ◽  
Forest Patch ◽  
Forest Sites ◽  
Before And After ◽  
Trade Control

Moratoria on international trade are frequently used to protect threatened species but few studies have examined their effectiveness in allowing populations to recover. We present population data collected before and after a moratorium on trade in the citron-crested cockatoo Cacatua sulphurea citrinocristata, a distinctive subspecies of the yellow-crested cockatoo endemic to Sumba, Indonesia. Before legal trade ceased in 1993 numbers of cockatoos leaving Sumba averaged c. 1,600 per year, and the 1992 population, estimated at 3,200, surely could not sustain such a level of trade. We surveyed cockatoos in four forest patches on Sumba in 1992, and then surveyed these same forest patches 10 years later, using the same field methods. Forest cover within the four patches was similar between years. We recorded a statistically significant increase in overall cockatoo density, from c. 2 birds per km2 in 1992 to >4 per km2 in 2002. Group sizes were also larger in 2002 than in 1992. Densities at two forest sites had increased considerably, at another the population was stable, but at one small forest patch a small population in 1992 had probably decreased. While the population has made a modest recovery, densities remain low compared to cockatoo populations elsewhere. Illegal trade is known to persist and its volume should be monitored closely.

STUDIES ON PLAQUE VARIANTS OF COXSACKIEVIRUS B5 BY BURST ANALYSES

1967 ◽  
Vol 13 (2) ◽  
pp. 167-172
Author(s):  
Jack Konowalchuk ◽  
Joan I. Speirs
Keyword(s):  
Cell Lines ◽  
Large Population ◽  
Small Population ◽  
Monkey Kidney ◽  
Large Plaque ◽  
Parent Culture ◽  
Normal Monkey ◽  
Small Pool ◽  
Selection For ◽  
Section Analysis

Propagation of coxsackievirus B5 on cell lines revealed two variants, one that yields small plaques and is stable and another that is large but variable in size. Multiple-burst studies on the large-plaque pool showed the existence of two different population sections. Analysis of a sample from a plaque belonging to the small population section showed a progeny of small plaques while a similar analysis from a plaque in the large population section produced plaques of varying size but whose mean plaque diameter resembled that of the parent culture. Repeated selection for smallness from plaques in the large population section resulted in small plaques and a shift from the large to the small population section. Analysis of the small pool virus on monkey kidney monolayers revealed the presence of a few typical monkey kidney plaques which differed from normal monkey kidney plaques by producing only small plaques on HEp-2 monolayers.

scholarly journals Genetic algorithms - variable size populations of chromosomes. An adaptive approach

2018 ◽  
Vol XIX (1) ◽  
pp. 393-399
Author(s):  
Maniu R
Keyword(s):  
Genetic Algorithms ◽  
Negative Impact ◽  
Large Population ◽  
Search Space ◽  
Global Optimum ◽  
Small Population ◽  
Local Optimum ◽  
Variable Size ◽  
Algorithm Operation

The size of the chromosome population is an essential parameter of genetic algorithms. A large population involves a large amount of calculations but provides a complete scroll of the search space and the increased probability of generating a global optimum. A small population size, through the small number of operations required, causes a quick run of the algorithm, with increasing the probability of detecting a local optimum to the detriment of the global one. This paper proposes the use of an adaptive, variable size of chromosome population. We will demonstrate that this approach leads to an acceleration of the algorithm operation, without having a negative impact on the quality of provided solutions.

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