• Title/Summary/Keyword: Negative binomial regression

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Causal Relationship between Structural Characteristics of Metropolitan Neighborhoods and Homicide (도시지역의 사회구조적 특성과 살인범죄와의 인과관계 : 서울시 행정동을 중심으로)

  • Cheong, Jinseong;Kang, Wook
    • The Journal of the Korea Contents Association
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    • v.13 no.3
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    • pp.152-161
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    • 2013
  • This study attempted to test the causal effect of structural characteristics of metropolitan neighborhoods on crime, based on the ecological model of crime explanation. To this end, a Negative Binomial Regression analysis was performed for Seoul's 424 Dong Districts. Results showed that the incidence of homicide increases as much as the scales of economic disadvantage, family disruption, and commercial land use go worse. It suggested that family integrity is one of the most strong and consistent factors that could deter crime in neighborhood's contexts. Economic disadvantage and commercial land use were also critical targets as crime-generating factors. Reasoning with the results of past studies implied that neighborhood-specific approaches need to be developed for effective crime prevention. Although a few limitations could raise a caveat against such interpretation of the results, the value of this research would not be simply denied as the first attempt to utilize all Dong districts of Seoul. It is expected that this study contributes to activating Dong level research and developing effective crime control policy.

How Does the Regulation of Location Affect Firm's Management and Innovation Performance? (정부의 지역 입지규제는 기업 경영 및 혁신성과에 어떤 영향을 미치는가? -평택(경기도)과 천안(충청남도)지역 기업 비교분석을 중심으로-)

  • Seo, Young-Woong;Choi, Seok-Joon;Lee, Si-Wook
    • Journal of Korea Technology Innovation Society
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    • v.15 no.3
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    • pp.586-603
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    • 2012
  • In order to relieve overcrowding, the Korean government has regulated firm's locations in the capital region of Korea. However, the standard of regulation mainly depends on the place of province. Using KIS-Value data of firms that are located Pyeong-taek(the Capital area) or Cheon-an(Non Capital area), in close proximity to each other, we utilize OLS and negative binomial regression models for identifying the difference of firms' management and innovation performance in terms of firms' location difference(regulation difference). Our analysis shows that innovation performance of firms in Cheon-an does better than Pyeong-taek's, but management performance has no gaps between them. This result indicates that the regulation of firm's location has influence on firm's innovation performance. Thus, regulation policy regarding firms' location need to be minutely amended.

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A Study on Optimizing Depot Location in Carsharing Considering the Neighborhood Environmental Factors (근린환경 요인을 고려한 카셰어링 대여소 배치 방안 연구)

  • Seo, Jeemin;Sheok, Chongsoo
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.16 no.5
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    • pp.49-59
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    • 2017
  • In this study, We analyzed the characteristics of carsharing use and revealed the environmental factors influencing carsharing use using the records of carsharing had been operated in Incheon during 2016. The records show a higher ratio of male users, a big portion of 20s and 30s, and ascending trends in the use of elderly people and short distances compared to the past. We analyzed the relationship between carsharing use and neighborhood environmental factors using the negative binomial regression model. It was found that carsharing was more active in areas where have many public transportation users and higher portion of residential buildings. Therefore, it was concluded that these areas can be suitable candidates for placing new carsharing rental sites to expect more active carsharing use.

Development of a Safety Performance Function for Expressway Tollgates (고속도로 영업소 구간 안전성능함수 개발)

  • Lee, Taehun;Kwak, Ho-Chan;Kim, Dong-Kyu;Kho, Seung-Young
    • Journal of Korean Society of Transportation
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    • v.33 no.1
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    • pp.81-89
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    • 2015
  • Crashes that occur at tollgates have different characteristics compared to those of the mainline on expressways in terms of crash cause, crash type, and vehicle type. Due to this fact, the safety performance function (SPF) focused on the expressway tollgates, apart from the mainline, should be developed. The aim of this study is, therefore, to identify the influential factors and develope a SPF for crashes at tollgates. Firstly, we established independent variables affecting crashes at tollgates through literature review and descriptive statistical analysis. Based on these variables, two negative binomial regression models with different form of independent variables were developed and goodness-of-fits of each model were compared. According to the results, the number of crashes increases i) as AADT, Hi-pass rate, and heavy vehicle rate increase, ii) as average lane width decreases, iii) on the mainline tollgate type. The safety performance function developed in this study could be applied to select hot-spots for expressway tollgates.

Macro-Level Accident Prediction Model using Mobile Phone Data (이동통신 자료를 활용한 거시적 교통사고 예측 모형 개발)

  • Kwak, Ho-Chan;Song, Ji Young;Lee, In Mook;Lee, Jun
    • Journal of the Korean Society of Safety
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    • v.33 no.4
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    • pp.98-104
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    • 2018
  • Macroscopic accident analyses have been conducted to incorporate transportation safety into long-term transportation planning. In macro-level accident prediction model, exposure variable(e.g. a settled population) have been used as fundamental explanatory variable under the concept that each trip will be subjected to a probable risk of accident. However, a settled population may be embedded error by exclusion of active population concept. The objective of this research study is to develop macro-level accident prediction model using floating population variable(concept of including a settled population and active population) collected from mobile phone data. The concept of accident prediction models is introduced utilizing exposure variable as explanatory variable in a generalized linear regression with assumption of a negative binomial error structure. The goodness of fit of model using floating population variable is compared with that of the each models using population and the number of household variables. Also, log transformation models are additionally developed to improve the goodness of fit. The results show that the log transformation model using floating population variable is useful for capturing the relationships between accident and exposure variable and generally perform better than the models using other existing exposure variables. The developed model using floating population variable can be used to guide transportation safety policy decision makers to allocate resources more efficiently for the regions(or zones) with higher risk and improve urban transportation safety in transportation planning step.

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.

Altmetrics: Factor Analysis for Assessing the Popularity of Research Articles on Twitter

  • Pandian, Nandhini Devi Soundara;Na, Jin-Cheon;Veeramachaneni, Bhargavi;Boothaladinni, Rashmi Vishwanath
    • Journal of Information Science Theory and Practice
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    • v.7 no.4
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    • pp.33-44
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    • 2019
  • Altmetrics measure the frequency of references about an article on social media platforms, like Twitter. This paper studies a variety of factors that affect the popularity of articles (i.e., the number of article mentions) in the field of psychology on Twitter. Firstly, in this study, we classify Twitter users mentioning research articles as academic versus non-academic users and experts versus non-experts, using a machine learning approach. Then we build a negative binomial regression model with the number of Twitter mentions of an article as a dependant variable, and nine Twitter related factors (the number of followers, number of friends, number of status, number of lists, number of favourites, number of retweets, number of likes, ratio of academic users, and ratio of expert users) and seven article related factors (the number of authors, title length, abstract length, abstract readability, number of institutions, citation count, and availability of research funding) as independent variables. From our findings, if a research article is mentioned by Twitter users with a greater number of friends, status, favourites, and lists, by tweets with a large number of retweets and likes, and largely by Twitter users with academic and expertise knowledge on the field of psychology, the article gains more Twitter mentions. In addition, articles with a greater number of authors, title length, abstract length, and citation count, and articles with research funding get more attention from Twitter users.

Characteristics and Models of Intersection Accidents by Elderly Drivers in the Case of Cheongju 4-legged Signalized Intersections (고령운전자 교차로 사고의 특성 및 모형 - 청주시 4지 신호교차로를 중심으로 -)

  • Park, Byung-Ho;Han, Sang-Wook;Kim, Kyung-Hwan
    • International Journal of Highway Engineering
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    • v.11 no.4
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    • pp.33-40
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    • 2009
  • This study deals with the traffic accidents of elderly drivers. The objectives are to comparatively analyze the characteristics of accident between the elderly and other drivers, and to develop the models of traffic accidents. In pursuing the above, this paper gives particular attentions to testing the differences between the above two groups, and developing the models(Poisson and negative binomial regression) using the data of Cheongju 4-legged signalized intersections. The main results analyzed are as follows. First, the differences between the elderly and other drivers' accidents were clearly defined by the time of day, accident type, etc. Second, 3 accident models which were all statistically significant were developed. Finally, the differences between elderly and other drivers' models were comparatively analyzed using the common and specific variables.

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Unions, Health and Safety Committees, and Workplace Accidents in the Korean Manufacturing Sector

  • Kim, Woo-Yung;Cho, Hm-Hak
    • Safety and Health at Work
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    • v.7 no.2
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    • pp.161-165
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    • 2016
  • Background: Despite the declining trend of workplace accidents in Republic of Korea, its level is still quite high compared with that in other developed countries. Factors that are responsible for high workplace accidents have not been well documented in Republic of Korea. The main purpose of this paper is to estimate the effects of unions and health and safety committees on workplace accidents in Korean manufacturing firms. We also allow for the interactions between unions and health and safety committees in the analysis. The results obtained in this paper will not only contribute to the literature in this field, but might also be useful for employers and worker representatives who are trying to find an effective way to reduce workplace accidents. Methods: This paper utilizes the 2012 Occupational Safety and Health Trend Survey data, which is a unique data set providing information on workplace injuries and illness as well as other characteristics of participatory firms, representative of the manufacturing industry in Republic of Korea. Results: In estimating the effects of unions and health and safety committees, we build a negative binomial regression model in which the interactions between unions and health and safety committees are permissible in reducing workplace accidents. Conclusion: Health and safety committees were found to reduce the incidence of accidents whereas unionized establishments have higher incidence of accidents than nonunionized establishments. We also found that health and safety committees can more effectively reduce accidents in nonunionized establishments. By contrast, nonexclusive joint committees can more effectively reduce accidents in unionized establishments.

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.