• Title/Summary/Keyword: 포아송 회귀분석

Search Result 79, Processing Time 0.025 seconds

Developing the Traffic Accident Prediction Model using Classification And Regression Tree Analysis (CART분석을 이용한 교통사고예측모형의 개발)

  • Lee, Jae-Myung;Kim, Tae-Ho;Lee, Yong-Taeck;Won, Jai-Mu
    • International Journal of Highway Engineering
    • /
    • v.10 no.1
    • /
    • pp.31-39
    • /
    • 2008
  • Preventing the traffic accident by accurately predicting it in advance can greatly improve road traffic safety. The accurate traffic accident prediction model requires not only understanding of the factors that cause the accident but also having the transferability of the model. So, this paper suggest the traffic accident diagram using CART(Classification And Regression Tree) analysis, developed Model is compared with the existing accident prediction models in order to test the goodness of fit. The results of this study are summarized below. First, traffic accident prediction model using CART analysis is developed. Second, distance(D), pedestrian shoulder(m) and traffic volume among the geometrical factors are the most influential to the traffic accident. Third. CART analysis model show high predictability in comparative analysis between models. This study suggest the basic ideas to evaluate the investment priority for the road design and improvement projects of the traffic accident blackspots.

  • PDF

The Development of Traffic Accident Severity Evaluation Models for Elderly Drivers (고령운전자 교통안전성 평가모형 개발)

  • Kim, Tae-Ho;Lee, Ki-Young;Choi, Yoon-Hwan;Park, Je-Jin
    • The Journal of The Korea Institute of Intelligent Transport Systems
    • /
    • v.8 no.2
    • /
    • pp.118-127
    • /
    • 2009
  • This study tries to develop model in order to assess personal factors of senior traffic accidents that are widely recognized as one of the social problems. For the current practice. it gathers data (Simulation & Questionnaire Survey) of KOTSA and conducts Poisson and Negative Binomial Regression Analysis to develop traffic accident severity model. The results show that elderly drivers' accidents are mainly affected by attentiveness selection, velocity prediction ability and attentiveness distribution ability in a positive(+) way. Second, non-senior drivers' accidents are also positively(+) influenced by attentiveness selection, velocity prediction, distance perception, attentiveness distribution ability and attentiveness diversion ability. Therefore, influencing factors of senior and non-senior drivers to vehicle accidents are different. This eventually poses a indication that preliminary education for car accident prevention should be implemented based up[n the distinction between senior drivers and non-senior drivers.

  • PDF

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
    • /
    • v.11 no.4
    • /
    • pp.33-40
    • /
    • 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.

  • PDF

What's Different about Fake Review? (조작된 리뷰(Fake Review)는 무엇이 다른가?)

  • Jung Won Lee;Cheol Park
    • Information Systems Review
    • /
    • v.23 no.1
    • /
    • pp.45-68
    • /
    • 2021
  • As the influence of online reviews on consumer decision-making increases, concerns about review manipulation are also increasing. Fake reviews or review manipulations are emerging as an important problem by posting untrue reviews in order to increase sales volume, causing the consumer's reverse choice, and acting at a high cost to the society as a whole. Most of the related prior studies have focused on predicting review manipulation through data mining methods, and research from a consumer perspective is insufficient. However, since the possibility of manipulation of reviews perceived by consumers can affect the usefulness of reviews, it can provide important implications for online word-of-mouth management regardless of whether it is false or not. Therefore, in this study, we analyzed whether there is a difference between the review evaluated by the consumer as being manipulated and the general review, and verified whether the manipulated review negatively affects the review usefulness. For empirical analysis, 34,711 online book reviews on the LibraryThing website were analyzed using multilevel logistic regression analysis and Poisson regression analysis. As a result of the analysis, it was found that there were differences in product level, reviewer level, and review level factors between reviews that consumers perceived as being manipulated and reviews that were not. In addition, manipulated reviews have been shown to negatively affect review usefulness.

A Spatial Statistical Approach to Migration Studies: Exploring the Spatial Heterogeneity in Place-Specific Distance Parameters (인구이동 연구에 대한 공간통계학적 접근: 장소특수적 거리 패러미터의 추출과 공간적 패턴 분석)

  • Lee, Sang-Il
    • Journal of the Korean association of regional geographers
    • /
    • v.7 no.3
    • /
    • pp.107-120
    • /
    • 2001
  • This study is concerned with providing a reliable procedure of calibrating a set of places specific distance parameters and with applying it to U.S. inter-State migration flows between 1985 and 1900. It attempts to conform to recent advances in quantitative geography that are characterized by an integration of ESDA(exploratory spatial data analysis) and local statistics. ESDA aims to detect the spatial clustering and heterogeneity by visualizing and exploring spatial patterns. A local statistic is defined as a statistically processed value given to each location as opposed to a global statistic that only captures an average trend across a whole study region. Whereas a global distance parameter estimates an averaged level of the friction of distance, place-specific distance parameters calibrate spatially varying effects of distance. It is presented that a poisson regression with an adequately specified design matrix yields a set of either origin-or destination-specific distance parameters. A case study demonstrates that the proposed model is a reliable device of measuring a spatial dimension of migration, and that place-specific distance parameters are spatially heterogeneous as well as spatially clustered.

  • PDF

A Zero-Inated Model for Insurance Data (제로팽창 모형을 이용한 보험데이터 분석)

  • Choi, Jong-Hoo;Ko, In-Mi;Cheon, Soo-Young
    • The Korean Journal of Applied Statistics
    • /
    • v.24 no.3
    • /
    • pp.485-494
    • /
    • 2011
  • When the observations can take only the non-negative integer values, it is called the count data such as the numbers of car accidents, earthquakes, or insurance coverage. In general, the Poisson regression model has been used to model these count data; however, this model has a weakness in that it is restricted by the equality of the mean and the variance. On the other hand, the count data often tend to be too dispersed to allow the use of the Poisson model in practice because the variance of data is significantly larger than its mean due to heterogeneity within groups. When overdispersion is not taken into account, it is expected that the resulting parameter estimates or standard errors will be inefficient. Since coverage is the main issue for insurance, some accidents may not be covered by insurance, and the number covered by insurance may be zero. This paper considers the zero-inflated model for the count data including many zeros. The performance of this model has been investigated by using of real data with overdispersion and many zeros. The results indicate that the Zero-Inflated Negative Binomial Regression Model performs the best for model evaluation.

Developing the Accident Models of Cheongju Arterial Link Sections Using ZAM Model (ZAM 모형을 이용한 청주시 간선가로 구간의 사고모형 개발)

  • Park, Byung-Ho;Kim, Jun-Yong
    • International Journal of Highway Engineering
    • /
    • v.12 no.2
    • /
    • pp.43-49
    • /
    • 2010
  • This study deals with the traffic accident of the Cheongju arterial link sections. The purpose of the study is to develop the traffic accident model. In pursuing the above, this study gives particular attentions to developing the ZAM(zero-altered model) model using the accident data of arterial roads devided by 322 small link sections. The main results analyzed by ZIP(zero inflated Poisson model) and ZINB(zero inflated negative binomial model) which are the methods of ZAM, are as follows. First, the evaluation of various developed models by the Vuong statistic and t statistic for overdispersion parameter ${\alpha}$ shows that ZINB is analyzed to be optimal among Poisson, NB, ZIP(zero-inflated Poisson) and ZINB regression models. Second, ZINB is evaluated to be statistically significant in view of t, ${\rho}$ and ${\rho}^2$ (0.63) values compared to other models. Finally, the accident factors of ZINB models are developed to be the traffic volume(ADT), number of entry/exit and length of median. The traffic volume(ADT) and the number of entry/exit are evaluated to be the '+' factors and the length of median to be '-' factor of the accident.

Convergence Analysis of the between Visual Analog Scale and Recovery Time according to the Types of Injury of Elite Wrestling Athletes (엘리트 레슬링선수들의 손상유형에 따른 시각적 상사 척도와 회복 기간과의 융복합분석)

  • Kim, June-Chul;Park, Ki-Jun
    • Journal of the Korea Convergence Society
    • /
    • v.11 no.9
    • /
    • pp.59-63
    • /
    • 2020
  • This study was conducted to investigate the relation between visual analogue scale and recovery time with type of injury that occur in elite wrestling athletes. The incidence rate of injury was analyzed the Poisson ratio, and the VAS and recovery time according to the type of injury were compared using the one-way ANOVA. In addition, the VAS and recovery time were examine the relationship using the Simple Linear Regression, and statistical significance level was α =.05. Injuries occurred most commonly in the ligament, followed by the muscle, cartilage and tendon.The VAS and recovery time according to the type of injury was statistically significant (p=.001, p=.001, respectively). The VAS and recovery time according to the type of injury was statistically significant (p=.001, p=.001). Also, increase in VAS of 1 point was associated with about 1.89 recovery time. These studies are expected to be useful as basic data for return to sports and safe training.

Characteristics of Geometric Conditions Affecting Freeway Traffic Safety at Nighttime, Sunrise, and Sunset (야간 및 일출몰 시간대 교통안전에 영향을 미치는 고속도로 기하구조 특성분석)

  • Hong, Sung-Min;Kim, Joon-Ki;Oh, Cheol
    • Journal of Korean Society of Transportation
    • /
    • v.30 no.4
    • /
    • pp.95-106
    • /
    • 2012
  • Driver's capability of identifying the change in freeway alignments and environments is one of important factors associated with traffic safety on freeways. In particular, driver's visibility and recognition capability are highly dependent on the altitude of the sun by sunset, sunrise, and nighttime. The purpose of this study is to identify the characteristics of geometric conditions affecting crash occurrences at sunset, sunrise, and nighttime. Poisson and negative binomial regressions were adopted to predict freeway crash frequency in this study. Freeway crash data during 2007~2010 were used for developing the crash frequency models. A set of variables representing the characteristics of geometric conditions were identified as significant ones affecting crash occurrences. The results of this study would be useful in deriving effective countermeasures for preventing traffic crashes that mainly occur at sunset, sunrise, and nighttime on freeways.

Roles of Individual- and Country-level Social Capital in Entrepreneurial Activities of Crowdfunding (크라우드펀딩 창업 활동에서 개인 및 국가 수준 사회적 자본의 역할)

  • Oh, Sehwan;Rho, Sungho
    • The Journal of Information Systems
    • /
    • v.26 no.1
    • /
    • pp.1-19
    • /
    • 2017
  • Purpose This study examines the roles of individual- and country-level social capital in entrepreneurial activities from the context of crowdfunding. Design/methodology/approach Two primary sources were used for data collection. From Kickstarter, the largest U.S.-based crowdfunding platform, this study obtained 15,716 crowdfunding projects and individual-level social capital. For country-level social capital, the social capital index from the 2016 Legatum Prosperity Index was utilized. By matching individual- and country-level social capital for each crowdfunding project, this research estimates the role of social capital in entrepreneurial activities at the individual and country level using the Poisson regression and the negative binomial regression. Findings Individual-level social capital measured by the number of Facebook friends, the number of other crowdfunding projects that a crowdfunding project founder invested in, and the word count of the description of a crowdfunding project are positively associated with the number of crowdfunding projects created by founders. The country-level social capital measured by aggregated social capital index is also positively associated with the number of crowdfunding projects created by founders. Both individual- and country-level social capital have a positive impact on entrepreneurial activities in terms of the creation of new crowdfunding projects.