## 1 Introduction
Some previous research on Japanese high-speed railway confirmed the \"straw effects\" in the mid-1990s [9], which consequently resulted in small cities gradually becoming an appendage of major cities and the dramatic decrease in employment, particularly service industries, without positive spillover effects. Regarding Korea, coupled with the operation of high-speed transport, many studies have found these adverse effects. [PERSON] (1994) found that, with the operation of a new highway, customers of a major department store in the regional city experienced a decrease, due to the higher accessibility of superior shopping malls in Seoul [24]. In recent studies, some researchers attempted to measure a straw effect by increasing daytime travelers in the Seoul area with the opening of KTX, and found that major cities get more marginal benefits than local towns [25; 26; 27]. However, some other studies also argued that there is little evidence of the straw effect in Korea. The study showed that the growth rate of the population in Seoul Metropolitan Areas before KTX was 16.1% from 1999 to 2003, but the rate dropped to 12.5% after KTX opened, from 2004 to 2007 [28]. Therefore, there are still no conclusive results on the socio-economic impacts of newly built transport systems. The straw effects of new HSRs may result in an unbalanced economic landscape and higher local dependency on significant cities [1]. Moreover, in Korea, there are still some controversies on whether or not the local human resources are concentrated in the metropolitan areas due to the new HSR construction [1; 29]. [PERSON] et al. (2010) found that the KTX construction would alleviate the excessive agglomeration of the population and employment in Seoul city [30]. Similarly, [PERSON] and [PERSON] (2016) found that the KTX construction stimulated the increase in population and industry in lagging areas, as well as local highway accessibility without the straw effects [31]. In general, little research has paid attention to the negative externalities of the new HSR network [31], especially the straw effect. This paper will examine the straw effect by a case study on the operation of KTX in Korea. In order to analyze the change in interregional social-economic activity patterns after the KTX opening, we introduced the concept of interregional economic dependency, based on the center-periphery theory proposed by [PERSON] (1950), which distinguishes the role in global economic development that countries in the core has played from those who are not [14]. Peripheral countries will, to a large extent, depend on core countries to get manufactured goods and the consumption of services. Similarly, this theory can also be applied to cities within a country to show their different transport positions. As the traffic volume between two cities can, to some degree, reflect the degree of connection between them, we used it to represent the strength of city's attachment to the city's interest. Therefore, the more traffic volume flow in the city \(i\) from the city \(j\), the more dependent city \(j\) becomes on city \(i\). In previous studies, economic dependency was measured by the number of floating populations, such as commuting traffic [32; 33; 34]. However, in most studies, the quantification of dependency is limited by the measure of commuting traffic, so this study uses interregional travel OD (Origin and Destination) data to deal with this problem from the perspective of economic dependency. The purpose of this paper was to examine if there exists a straw effect resulting from two new HSRs in Korea. This study makes the following contributions to the literature: First, we examine the straw effect from the perspective of economic dependency derived from the center-periphery theory. Second, we construct a panel data model that includes variables, such as traffic volume by each city of interest and city characteristic variables, to conduct the empirical analysis of the impacts of the new HSR.