• Title/Summary/Keyword: 음이항

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Estimating the Economic Value of Recreation Sea Fishing in the Yellow Sea: An Application of Count Data Model (가산자료모형을 이용한 서해 태안군 유어객의 편익추정)

  • Choi, Jong Du
    • Environmental and Resource Economics Review
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    • v.23 no.2
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    • pp.331-347
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    • 2014
  • The purpose of this study is to estimate the economic value of the recreational sea fishing in the Yellow Sea using count data model. For estimating consumer surplus, we used several count data model of travel cost recreation demand such as a poisson model(PM), a negative binomial model(NBM), a truncated poisson model(TPM), and a truncated negative binomial model(TNBM). Model results show that there is no exist the over-dispersion problem and a NBM was statistically more suitable than the other models. All parameters estimated are statistically significant and theoretically valid. The NBM was applied to estimate the travel demand and consumer surplus. The consumer surplus pre trip was estimated to be 254,453won, total consumer surplus per person and per year 1,536,896won.

Study on Effect of Low Visibility Condition at Nighttime on Traffic Accident (야간의 시인성 저하가 교통사고에 미치는 영향 진단 -경기도 지역의 경부, 서해안, 영동, 서울외곽순환고속도로를 중심으로-)

  • Lee, Seung-Sin;Kim, Tae-Heon;Son, Bong-Soo
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.13 no.2
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    • pp.12-26
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    • 2014
  • This Study deals with effect of low visibility condition at nighttime on traffic accident. Roads for experiment of this study are Gyeongbu expressway, Seohaean expressway, Yeongdong expressway and Seoul beltway in Gyeonggi province. For this study, I subdivided basic straight section of them into 58 short section. And I analyzed effect of low visibility condition by darkness at nighttime on traffic accident by using 410 traffic accidents between January 1, 2009 and June 30, 2012 on those sections. The Quasi-experimental and negative binomial regression were applied to analyze effect of low visibility condition at nighttime on traffic accident. In this study, I only analyzed visibility difference of daytime and nighttime on traffic accident except other effective variables on traffic accidents. As a result, I have found that it is for low visibility condition at nighttime to have effect on traffic accidents at such specific conditions as Los A speed is maintained in basic straight section of expressway in fine weather. And I tried to do various analysis on types and causes of traffic accidents using the result of analysis.

An Analysis on the Determinants of Employed Labour Quantity in the Fishing Industry (어가의 고용량 결정요인 분석)

  • Kim, Tae-Hyun;Park, Cheol-Hyung;Nam, Jongoh
    • Environmental and Resource Economics Review
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    • v.27 no.3
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    • pp.545-567
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    • 2018
  • This study applied and compared Poisson model, negative binomial model, zero inflated Poisson model, and zero inflated negative binomial model to estimate determinants of employed labour quantity. To estimate each of models, this study used fisheries census data which were obtained at microdata integrated service running by Statistics Korea. The study selected zero inflated negative binomial model according to the Vuong test and Likelihood-ratio test. In addition, the study estimated fishing village's practical changes on employed labour quantity as analyzing changes from 2010 to 2015. The results showed that the household with fishing vessels and high selling price had a significant effect on decrease of the labour quantities. Meanwhile, the longer work experience of the household, the more significant the increase in the labour quantities. In conclusion, this study presented that capitalized fishing household and the acceleration of aging had a significant impact on the change in the labour quantities.

Zero In ated Poisson Model for Spatial Data (영과잉 공간자료의 분석)

  • Han, Junhee;Kim, Changhoon
    • The Korean Journal of Applied Statistics
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    • v.28 no.2
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    • pp.231-239
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    • 2015
  • A Poisson model is the first choice for counts data. Quasi Poisson or negative binomial models are usually used in cases of over (or under) dispersed data. However, these models might be unsuitable if the data consist of excessive number of zeros (zero inflated data). For zero inflated counts data, Zero Inflated Poisson (ZIP) or Zero Inflated Negative Binomial (ZINB) models are recommended to address the issue. In this paper, we further considered a situation where zero inflated data are spatially correlated. A mixed effect model with random effects that account for spatial autocorrelation is used to fit the data.

A Study on Factors Influencing Floating Population using Mobile Phone Data in Urban Area (이동통신 자료를 활용한 대도시 유동인구 영향요인 분석)

  • Kwak, Ho-Chan;Song, Ji Young;Eom, Jin Ki;Kim, Kyoung Tae
    • Journal of The Korean Society For Urban Railway
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    • v.6 no.4
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    • pp.373-381
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    • 2018
  • The floating population that is index to figure out dynamic activities in urban area will be important in urban railway planning, but it is not useful because it is collected by posterior method. This study aims to investigate factors influencing floating population. The floating population data that was collected in Seoul for a month in December 2013 is used as dependent variable, and the negative binomial regression analysis is used in modelling. The number of households, number of employees, number of subway stations, and number of bus lines variables are statistically significant in predicting floating population.

Study on Shared E-scooter Usage Characteristics and Influencing Factors (공유 전동킥보드 이용 특성 및 영향요인에 관한 연구)

  • Kim, Su jae;Lee, Gyeong jae;Choo, Sangho;Kim, Sang hun
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.20 no.1
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    • pp.40-53
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    • 2021
  • Recently, shared dockless e-scooter usage has rapidly increased, rather than the station-based shared mobility service, because of convenience. This transition leads to new social problems in urban areas such as increased traffic accidents and hindrance of pedestrian environments. In this study, we analyze the usage characteristics of shared e-scooters in Seoul, and identify factors influencing demand for shared e-scooters by developing a negative binomial regression model. As a result, the usage characteristics show that the average trip distance, the average trip duration, and the average trip speed were 1.5km, 9.4min, and 10.3km/h, respectively. Demographic factor, transport facility factors, land use factors, and weather factors have statistically significant impacts on demand for shared e-scooters. The results of this study will be used as basic data for suggesting effective operation strategies for areas with higher shared e-scooter demand and for establishing transport policies for facilitating shared e-scooter usage.

Development of a Pedestrian Accident Exposure Estimation Modelconsidering Walking Conflicts (보행상충을 고려한 보행사고 노출 추정 모형 개발)

  • Iljoon Chang;Nam ju Kwon;Se-young Ahn
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.22 no.2
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    • pp.54-63
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    • 2023
  • Pedestrian traffic needs to be accurately quantified to predict effectively pedestrian traffic accidents, however, pedestrian traffic is more difficult to measure than vehicle traffic. In this study, we suggest the time-and cost-effective application of mobile closed-circuit television (CCTV) using a smartphone as an alternative that can collect and analyze real-time data with little. In the present investigation, the pedestrian-vehicle conflict that can develop into an accident was defined as the pedestrian accident exposure. After installing mobile CCTV in 40 sections of Dongseong-ro, Daegu, the pedestrian accident exposure was estimated through negative binomial regression analysis using the collected data. The results of the analysis showed statistically significant changes in the pedestrian accident exposure variables. Based on the present results, a pedestrian accident exposure estimation model was developed which can be used in sections where pedestrian accidents may occur.

Study on the Development of Truck Traffic Accident Prediction Models and Safety Rating on Expressways (고속도로 화물차 교통사고 건수 예측모형 및 안전등급 개발 연구)

  • Jungeun Yoon;Harim Jeong;Jangho Park;Donghyo Kang;Ilsoo Yun
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.22 no.1
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    • pp.1-15
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    • 2023
  • In this study, the number of truck traffic accidents was predicted by using Poisson and negative binomial regression analysis to understand what factors affect accidents using expressway data. Significant variables in the truck traffic accident prediction model were continuous driving time, link length, truck traffic volume. number of bridges and number of drowsy shelters. The calculated LOSS rating was expressed on the national expressway network to diagnose the risk of truck accidents. This is expected to be used as basic data for policy establishment to reduce truck accidents on expressways.

Analysis of Accident Characteristics and Development of Accident Models in the Signalized Intersections of Cheongju and Cheongwon (지방부 신호교차로 사고특성분석 및 모형개발 (청주.청원을 중심으로))

  • Park, Byung-Ho;Yoo, Doo-Seon;Yang, Jeong-Mo;Lee, Young-Min
    • Journal of Korean Society of Transportation
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    • v.26 no.2
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    • pp.35-46
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    • 2008
  • The purposes of this study are to analyze the characteristics and to develop the models of traffic accidents. In pursuing the above, this study gives particular attentions to developing the models(multiple linear, poisson and negative binomial regression) using the data of Cheongju and Cheongwon signalized intersections. The main results analyzed are as follows. First, the accident characteristics of rural area were defined by factor. Second, 4 accident models which are all statistically significant were developed. Finally, such the variables as $X_2$ and $X_{11}$ were evaluated to be specific variables which reflect the characteristics of rural area.

Bayesian Analysis for the Zero-inflated Regression Models (영과잉 회귀모형에 대한 베이지안 분석)

  • Jang, Hak-Jin;Kang, Yun-Hee;Lee, S.;Kim, Seong-W.
    • The Korean Journal of Applied Statistics
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    • v.21 no.4
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    • pp.603-613
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    • 2008
  • We often encounter the situation that discrete count data have a large portion of zeros. In this case, it is not appropriate to analyze the data based on standard regression models such as the poisson or negative binomial regression models. In this article, we consider Bayesian analysis for two commonly used models. They are zero-inflated poisson and negative binomial regression models. We use the Bayes factor as a model selection tool and computation is proceeded via Markov chain Monte Carlo methods. Crash count data are analyzed to support theoretical results.