• Title/Summary/Keyword: logit 모델

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Formulating the Landscape Preference Model Using a Mixed Conditional Logit (조건부 로짓함수를 이용한 경관선호 모델: 지리산 국립공원 방문자를 대상으로)

  • Lee, Deokjae
    • Journal of Korean Society of Forest Science
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    • v.95 no.6
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    • pp.768-777
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    • 2006
  • The purpose of this study lies in formulating the landscape preference model using a conditional logit that involves the effect of visual elements as well as landscape itself on landscape preferences. To measure landscape preferences, a photo-questionnaire composed of paired photographs of the Cairngorms National Park of Scotland and the Jirisan National Park of Korea was distributed to visitors to the Jirisan National Park of Korea. Visual elements of landscape quantitatively measured by photogrammetry were reduced to orthogonal principal components that were subsequently used as explanatory variables in a conditional logit. As a result, the mixed conditional logit including the effect of landscape itself satisfied the Independence of Irrelevant Alternatives (IIA) property and showed reliable goodness of fit (${\rho}^2=0.25$). It was concluded that the mixed conditional logit including the effect of landscape itself was appropriate for landscape preference model rather than usual conditional logit excluding the effect.

Effects of Multicollinearity in Logit Model (로짓모형에 있어서 다중공선성의 영향에 관한 연구)

  • Ryu, Si-Kyun
    • Journal of Korean Society of Transportation
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    • v.26 no.1
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    • pp.113-126
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    • 2008
  • This research aims to explore the effects of multicollinearity on the reliability and goodness of fit of logit model. To investigate the effects of multicollinearity on the multinominal logit model, numerical experiments are performed. The exploratory variables(attributes of utility functions) which have a certain degree of correlations from (rho=) 0.0 to (rho=) 0.9 are generated and rho-squares and t-statistics which are the indices of goodness of fit and reliability of logit model are traced. From the well designed numerical experiments, following findings are validated : 1) When a new exploratory variable is added, some of rho-squares increase while the others decrease. 2) The higher relations between generic variables lead a logit model worse with respect to goodness of fit. 3) Multicollinearity has a tendency to produce over-evaluated parameters. 4) The reliability of the estimated parameter has a tendency to decrease when the correlations between attributes are high. These results suggest that we have to examine the existence of multicollinearity and perform the proper treatments to diminish multicollinearity when we develop logit model.

An Analysis on an Action about Port Choice of Shipper using Fuzzy-Neural Network (퍼지-뉴로를 이용한 화주의 항만선택 행동 분석)

  • Jang, Woon-Jae;Keum, Jong-Soo
    • Journal of Navigation and Port Research
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    • v.31 no.8
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    • pp.725-731
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    • 2007
  • This paper aims to analyze an action about a port choice of shipper between two ports. For this propose, this paper analyzed a port choice action for Kwangyang and Busan port using a fuzzy logic and neural network. Also, this paper compared classification performance of fuzzy-neural network to Logit model, and analyzed a port choice action into change Para-meta such as freight volumes and service standard.

The Analysis of Older Driver's Traffic Accident Characteristic at Express-way using Logit model (로짓모델을 이용한 고령운전자 고속도로 교통사고 특성 분석 연구)

  • Park, Jun-Tae;Kim, Young-Suck;Lee, Soo-Beom
    • International Journal of Highway Engineering
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    • v.11 no.4
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    • pp.1-7
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    • 2009
  • Traffic accident by aging drivers is expected to be on the rise rapidly as the number of aging drivers is rising along with the aging trend being progressed. In this study, traffic accident features depending on the classification of aging population and non aging one was evaluated. As a result of this evaluation, effect factors influencing over the aging population was found to be expressed differently from that of the non aging one. Odds ratio between the aging population and non aging one was evaluated through logit model and a model with potential accident probability of the aged drivers was developed. Accident risk of the aged drivers under the condition of curved road, cutting section and moistured road was revealed to be higher than that of the non aging population.

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Usefulness of In-store Spotting Survey in Developing a Supermarket Location Analysis Model (내점객 인터뷰에 근거한 슈퍼마켓 입지분석 모델의 실용성 평가)

  • 서성무;고윤배
    • Asia Marketing Journal
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    • v.1 no.1
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    • pp.5.1-5.11
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    • 1998
  • 이 연구는 2차자료가 부족한 우리나라 슈퍼마켓 업체의 여건을 감안하여 간편하게 활용할 수 있는 입지분석 모델의 가능성을 탐구하였다. 연구모델은 두 가지 기준을 근거로 모두 네가지 모델을 설정하고 비교검토했다. 먼저 표본추출방법에 의해 내점객표본과 지역할당표본으로 분류하고, 이것을 다시 포함하는 변수의 범위에 따라 축소모델과 확장모델로 구분하였다. 공간상호작용모델의 추정에는 MNL(Multinomial Logit)방식을 이용했다. 분석결과 내점객표본으로 조사해서 얻은 응답자의 주거지와 주로 찾는 점포, 그리고 사전적으로 입수한 경쟁점포의 매장면적, 인접점포까지의 거리에 대한 자료만을 이용해서 추정한 가장 간단한 모델이 비교적 만족스러운 결과를 나타냈다.

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Multiple Regression Analysis between Weather Factor and Line Outage using Logit Model (로짓(Logit) 모델을 이용한 날씨요소와 송전선로 고장의 다중회귀분석)

  • Shin, Dong-Suk;Lee, Youn-Ho;Kim, Jin-O;Lee, Baek-Seok;Bang, Min-Jae
    • Proceedings of the KIEE Conference
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    • 2004.11b
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    • pp.187-189
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    • 2004
  • This paper investigates the effect of weather factors(such as winds, rain, snows, temperature, clouds and humidity) on transmission line outages. The result shows that weather variables have significant effects on the transmission line historical outages and the relationship between them is nonlinear. Multiple regression analysis using Logit model is proved to be appropriate in forecasting line failure rate in KEPCO systems. It could also provide system operators with useful informations about system operation and planing.

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Analysis of methods for the model extraction without training data (학습 데이터가 없는 모델 탈취 방법에 대한 분석)

  • Hyun Kwon;Yonggi Kim;Jun Lee
    • Convergence Security Journal
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    • v.23 no.5
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    • pp.57-64
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    • 2023
  • In this study, we analyzed how to steal the target model without training data. Input data is generated using the generative model, and a similar model is created by defining a loss function so that the predicted values of the target model and the similar model are close to each other. At this time, the target model has a process of learning so that the similar model is similar to it by gradient descent using the logit (logic) value of each class for the input data. The tensorflow machine learning library was used as an experimental environment, and CIFAR10 and SVHN were used as datasets. A similar model was created using the ResNet model as a target model. As a result of the experiment, it was found that the model stealing method generated a similar model with an accuracy of 86.18% for CIFAR10 and 96.02% for SVHN, producing similar predicted values to the target model. In addition, considerations on the model stealing method, military use, and limitations were also analyzed.

A Model to Forecast Rice Blast Disease Based on Weather Indexing (기상지수에 의한 벼도열병 예찰의 한 모델)

  • Kim Choong-Hoe;MacKenzie D. R.;Rush M. C.
    • Korean Journal Plant Pathology
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    • v.3 no.3
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    • pp.210-216
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    • 1987
  • A computer program written to predict blast occurrence based on micro climatic events was developed and tested as an on-site microcomputer in field plots in 1984 and 1985. A microcomputer unit operating on alkaline batteries; continuously monitored air temperature, leaf wetness, and relative humidity; interpreted the microclimate information in relation to rice blast development and displayed daily values (0-8) of blast units of severity (BUS). Cumulative daily BUS values (CBUS) were highly correlated with blast development on the two susceptible cultivars, M-201 and Brazos grown in field plots. When CBUS values were used to predict the logit of disease proportions, the average coefficients of determination $(R^2)$ between these two factors were 71 to $91\%$, depending on cultivar and year. This was a significant improvement when compared to 61 to $79\%$ when days were used as a predictor of logit disease severity. The ability of CBUS to predict logit disease severity was slightly less with Brazos than M-201. This is significant inasmuch as Brazos showed field resistance at mid-sea­son. The results in this study indicate that the model has the potential for future use and that the model could be improved by incorporating other variables associated with host plants and pathogen races in addition to the key environmental variables.

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Public Transportation Information Profit Model in Using CVM(Focused on BIT) (CVM기법을 이용한 대중교통수익모델 연구(BIT를 중심으로))

  • Park, Bum-Jin;Moon, Byeong-Sup
    • The Journal of the Korea Contents Association
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    • v.11 no.8
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    • pp.459-467
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    • 2011
  • BIS(Bus Information Systems) supplies the bus arrived time information for users in using BIT(Bus Information Terminal) installed on the bus stop. BIT is the device using peoples directly. So, BIT need a quick response when it flew. These are an important factor in the strategy of the BIS maintenance. BIT need a maintenance cost to operate smoothly. So, Suppose that commercial advertisement can be displayed on BIT screen in this study. And we researched an advertisement rates of the optimum level in using Contingent Valuation Method. In addition, we analyzed a characteristic of user's depending on each time using multinomial Logit Modeling method, and studied for BIT operation and ad. displaying strategy considered user's sex, ages and using times.

A Gap-acceptance Model Considering Driver's Propensity at Uncontrolled Intersection (운전자 특성 등을 고려한 무통제교차로의 간격수락 모델)

  • Jang, Jeong-Ah;Lee, Jung-Woo;Choi, Kee-Choo
    • Journal of Korean Society of Transportation
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    • v.26 no.6
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    • pp.71-80
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    • 2008
  • Typically uncontrolled intersections are characterized by the absence of signal, stop and yield sign, and by very light traffic volume. In this study, a gap acceptance model for such uncontrolled intersections has been modeled. The motivation is to identify the behavior of drivers so that the traffic flow phenomena can be easily understood. For this, actual traffic survey was accomplished at intersections in Suwon and the data have been fed into modeling process. The logit model was used and the results showed that total delay experienced by drivers, turning right movement, age, sex, and the existence of passenger affected gap acceptance. For example, male drivers, with experiencing longer delay and having passenger(s) with them, accepted shorter gaps. These identified characteristics regarding gap acceptance could be used for facility design and/or safety oriented traffic information dissemination near uncontrolled intersections.