• Journal of Korean Society of Transportation
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• v.30 no.3
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• pp.57-70
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• 2012

Variable speed limit(VSL) is a useful speed management tool for alleviating traffic congestion and enhancing traffic safety. The purpose of this study is to identify promising freeway segments for safety enhancement through VSL operations. An ordered probit model was adopted to capture factors affecting freeway crash severity that can be used to support decision making for selecting the promising segments. Pseudo elasticity and marginal effects, which are outcomes of the ordered probit analysis, were used to determine priority of promising segments for traffic safety. The results of this study would be useful in installing VSL systems and developing traffic control and operations strategies in practice.

• Journal of Digital Convergence
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• v.18 no.9
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• pp.93-101
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• 2020

Although concerns about the opinion shopping have been continuously raised in the audit market, there has been little research on empirical evidence on the existence of audit opinions. For this reason, this study empirically confirmed whether the opinion shopping exists. At first, we measured thresholds of audit opinion issuing of two groups(changed or not-changed auditors). After that, the difference analysis was conducted to verify whether the thresholds of the audit opinion issuing was significant difference between two groups. As a result of the study, there was no significant difference in the thresholds of audit opinion issuing between two groups. This result can be interpreted that the audit opinion shopping is not a general phenomenon in the external audit market. The contribution of this study is to empirically confirmed that audit opinion shopping does not exist in the external audit market.