• Journal of the Korean Data and Information Science Society
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• v.24 no.6
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• pp.1543-1550
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• 2013

In this paper, we study Bayesian estimation for the finite population proportion in binary data under selection bias. We use a Bayesian nonignorable selection model to accommodate the selection mechanism. We compare four possible estimators of the finite population proportions based on data analysis as well as Monte Carlo simulation. It turns out that nonignorable selection model might be useful for weekly biased samples.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.9
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• pp.5367-5370
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• 2013

Background: Having knowledge or estimation of cancer incidence is necessary for planning and implementation of any cancer prevention and control programs. Population-based registries provide valuable information to achieve these objectives but require extra techniques to estimate the incidence rate. The present study aimed to estimate the esophageal cancer incidence using a log-linear method based on Tehran population-based cancer registry data. Materials and Methods: New cases of esophageal cancer reported by three sources of pathology reports, medical records, and death certificates to Tehran Metropolitan Area Cancer Registry Center during 2002-2006 were entered into the study and the incidence rate was estimated based on log-linear models. We used Akaike statistics to select the best-fit model. Results: During 2002-2006, 1,458 new cases of esophageal cancer were reported by the mentioned sources to the population-based cancer registry. Based on the reported cases, cancer incidence was 4.5 per 100,000 population and this was estimated to be 10.5 per 100,000 by the log-linear method. Conclusions: Based on the obtained results, it can be concluded that an estimated incidence for 2004 of 8.3 per 100,000 population could be a good benchmark for the incidence of esophageal cancer in the population of Tehran metropolis.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.12
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• pp.7517-7522
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• 2013

Background: Cancer incidence rates are increasing particularly in developing countries. It is crucial for policy makers to know basic cancer epidemiology in each region to design comprehensive prevention plans. There have hitherto been no population-based data available for cancer in Khuzestan province. The present report is a first from the regional population-based cancer registry for the period of 2002-2009. Materials and Methods: Data were collected retrospectively reviewing all new cancer patients whom were registered in Khuzestan province cancer registry during an 8-year period (2002-2009). All cases were coded based on the ICD-O-3 coding system and collected data were computerized using SPSS (Chicago, IL) software, version 11.5. The age standardized incidence rates (ASRs) per 100,000 person-year for all cancers were computed using the indirect method of standardization to the world population. Results: During the 8-year study period, 16,801 new cancer cases were registered. Based on the computed ASRs, the five most frequent malignancies in females were breast (26.4 per 100,000), skin (13.6), colorectal (5.72), stomach (4.31) and bladder(4.07) and in males, the five most frequent were skin (16.0 per 100,000), bladder (10.7),prostate (7.64), stomach (7.17), and colorectal (6.32).The ASR for all malignancies in women was 92.5 per 100,000, and that for men was 87.4. Conclusions: The observed patterns from the analysis of Khuzestan cancer registry data will lead to better understanding of the epidemiology of various malignancies in this part ofthe country and consequently provide a useful guide for authorities to make efficacious decisions and policies about a cancer control program for south-west Iran.

• Journal of Oral Medicine and Pain
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• v.14 no.1
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• pp.25-34
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• 1989

The author performed on epidemiological study of the TMD in 189 elderly people and 195 young people with Helkimo index. The clinical dysfunction index was based on data from clinical examination and the anamestic dysfunction index was based on data from the interview with the investigated person. The results were as follows : 1. In the elderly population, 27.5% reported that they had subjectively symptom of TMD but 43.4% had sign and symptoms of TMD in clinical examination. 2. The mean values for maximal opening differed significantly between elderly and young populations, 47.22mm and 51.44mm (p<0.001) and less than a 40mm opening was observed 7.9% in elderly population, 0.5% in young population (p<0.001). 3. The mean values for lateral movement to the right and left did not differ with age, which were 8.56mm and 8.47mm in elderly population, 8.90mm and 8.81mm in young population, but the mean value for protrusion differed significantly between elderly and young populations, 6.89mm and 7.64mm (p<0.01). 4. A higher incidence of TMJ noise was recorded in the elderly and young populations than young population, especially crepitus, but a higher incidence of clicking was recorded in young population (p<0.05).

• Journal of Korean Society of Rural Planning
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• v.28 no.4
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• pp.1-9
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• 2022

Rural decline due to the decrease of the local population is an inevitable phenomenon, and a vicious cycle has been formed between a lack of basic living services and a population decrease in rural areas. Therefore, the study aims to derive the migration decision-making characteristics based on basic living service infrastructure data in rural areas. To do this, the population change over the past 20 years was categorized into six types, and the relationship between the classified population change types and the number of basic living service infrastructures was analyzed using decision tree analysis. Of the total 3,501 regions, 801 regions were the continuous decline type, of which 740 were rural areas. On the other hand, among 569 regions that were the continuous increase type, 401 regions were urban areas, confirming the population imbalance between rural and urban areas. As a result of the decision tree analysis on the relationship between population change types and the distribution of basic living service infrastructure, the number of daycare centers was derived as an important variable to classify the continuous increase type. Hospitals, parks, and public transportation were also found to be major basic living services affecting the classification of population change types.

• Asian Journal of Innovation and Policy
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• v.9 no.2
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• pp.223-239
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• 2020

It is important for urban planners and policy makers to understand complex, diverse urban demands and social structure, but this is not easy due to lack of data that represents the dynamics of residents at micro-geographical level. This paper explores how to create population data at at a micro-level by allocating population data to building. It attempted to allocate population data stored in a grid layer (100 meters by 100 meters) into a building footprint layer that represents the appearance of physical buildings. For the allocation, this paper describes a systemic approach that classifies grid cells into five prototypical patterns based on the composition of residential building types in a grid cell. This approach enhances allocation accuracy by accommodating heterogeneity of urban space rather than relying on the assumption of uniform spatial homogeneity of populations within an aerial unit. Unlike the methods that disaggregate population data to the parcel, this approach is more applicable to Asian cities where large multifamily residential parcels are common. However, it should be noted that this paper does not demonstrate the validity of the allocated population since there is a lack of the actual data available to be compared with the current estimated population. In the case of water and electricity, the data is already attached to an individual address, and hence, it can be considered to the purpose of the validation for the allocation. By doing so, it will be possible to identify innovative methods that create a population distribution dataset representing the comprehensive and dynamic nature of the population at the micro geographical level.

• Journal of Korean Neurosurgical Society
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• v.46 no.5
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• pp.443-450
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• 2009

Objective : We estimated the number of Korean adults with back pain and evaluated population-based associated factors of back pain from a representative sample data from the Fourth Korea National Health and Nutrition Examination Survey. Methods : The number of Korean adults who experienced back pain (experienced patients), those who experienced back pain lasting for three or more months during the past year (chronic patients), and those who were currently suffering from back pain (current patients) were estimated by analyzing the data from the fourth Korea National Health and Nutrition Examination Survey conducted in 2007 using surveyfreq procedure of the SAS statistical package. Population-based odds ratios for being experienced, chronic, and current patient according to demographic (age and gender), socioeconomic (education and occupation), and lifestyle factors (smoking, drinking, and exercise) were estimated using surveylogistic procedure. Results : It was estimated that there were 5,554,256 (proportion, 15.4%; 95% CI, 4,809,466 - 6,299,046) experienced patients, 2,060,829 (5.7%; 1,557,413-2,564,246) chronic patients, and 3,084,188 (8.5%; 2,600,197 - 3,568,179) current patients among 36,107,225 Korean adults aged 20-89 years in 2007. Each of explanatory variables was significantly associated with at least one of the response variables for back pain. Conclusion : Based on our study results, further efforts to investigate epidemiology of back pain, to evaluate associated factors, and to improve treatment outcomes are needed.

• Survey Research
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• v.12 no.2
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• pp.27-50
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• 2011

It is increasingly important to estimate daytime population for the sake of urban administration and urban economy. The estimation of daytime population using a census data on commute, however, has its own limits, particularly when applying to the metropolis such as Seoul which is dominated by the service industry. This study suggests a pedestrian flow as another estimate of daytime population and presents a methodology of Seoul Pedestrian Flow Survey. The data of pedestrian flow gives us a view into hourly and spatial distribution of daytime population, which cannot be provided by the use of census data. In addition, comparing with a census-based daytime population on the borough level show some features of a pedestrian flow as another estimate of daytime population.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.05a
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• pp.438-442
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• 2006

Reasonably accurate estimation of the exposed population to the distinct levels of noise is essential to the efficient management of urban environmental noise. This study proposes a method of calculating the number of exposed people to industrial noise by using GIS tool and noise mapping. The exposed population of noise based on estimation of the number of people that lived in each building in urban area is compared with the one based on density of population. This study suggests the six step method that consists of gathering the fundamental data, extracting the property from the digital map, noise mapping based on the three dimensional topography, estimating population that lives in each building, merging the various results with GIS tool, and estimating exposed population to industrial noise through analyzing the noise map with GIS tools

• Spatial Information Research
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• v.22 no.3
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• pp.89-99
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• 2014

The aim of this study is to represent the residential population distribution in Seoul, Korea more precisely through the dasymetric mapping method. Dasymetric mapping can be defined as a mapping method to calculate details from truncated spatial distribution of main statistical data by using ancillary data which is spatial data related to the main data. In this research, there are two types of data used for dasymetric mapping: the population data (2010) based on a output area survey in Seoul as the main data and the building footprint data including register information as ancillary spatial data. Using the binary method, it extracts residential buildings as actual areas where residents do live in. After that, the regression method is used for calculating the weights on population density by considering the building types and their gross floor areas. Finally, it can be reproduced three-dimensional density of residential population and drew a detailed dasymetric map. As a result, this allows to extract a more realistic calculating model of population distribution and draw a more accurate map of population distribution in Seoul. Therefore, this study has an important meaning as a source which can be applied in various researches concerning regional population in the future.