1 Exploring the Effects of Household Structure on Elderly Grocery Shopping Behavior in Korea Sang-Eon SEO 1 , Nobuaki OHMORI 2 and Noboru HARATA 3 1 Non-Member of JSCE, Dr. Eng., Dept. of Urban Eng., University of Tokyo (7-3-1, Hongo, Bunkyo-ku, Tokyo, Japan) E-mail: newlifeseo@yahoo.co.kr 2 Member of JSCE, Associate Professor, Dept. of Urban Eng., University of Tokyo (7-3-1, Hongo, Bunkyo-ku, Tokyo, Japan) E-mail: nobuaki@ut.t.u-tokyo.ac.jp 3 Member of JSCE, Professor, Dept. of Urban Eng., University of Tokyo (7-3-1, Hongo, Bunkyo-ku, Tokyo, Japan) E-mail: nhara@ut.t.u-tokyo.ac.jp Traditionally, Koreans in their old age tend to reside with adult children and receive physical and psy- chological support from them. This feature may have positive effects on the quality of life for the elderly. However, recent official statistics show Korea’s soaring elderly households residing without adult children, indicating a need to pay more attention to the effects of household structure on the elderly in order to im- prove the quality of life for the elderly. In this context, this study explored the effects of household structure on elderly grocery shopping behavior with a focus on grocery shopping frequency, accompanying be- havior, and enjoyment with grocery shopping activities by estimating full structural equation models. In addition, aggregate urban modeling applications on the relationship between accessibility and trip/tour frequency commonly produce either non-significant or negative associations which violate the basic economic theory, that is, lower travel cost leads to more travel. We speculated that individuals’ subjective satisfaction with activities could lead to such unreasonable results. Therefore, the other objective of this study is to identify the possible causes to lead the unreasonable relationship between accessibility and trip/tour frequency. First of all, a hypothesized single population model (using an entire survey dataset conducted in this study) was statistically tested by estimating a full structural equation model. Second, the entire survey dataset was segmented into four comparison groups by four dichotomous segmentation variables: co-residence with adult children, auto availability, presence of companions, and presence of daughters-in-law in the household. The results showed that co-residence with adult children and better family relationship significantly alleviate difficulties with elderly physical mobility and residential acces- sibility to grocery shopping places, consequently improving grocery shopping enjoyment of the elderly and then the quality of life for the elderly. Key Words : elderly,household structure, accessibility,quality of life,grocery shopping 1. INTRODUCTION Population aging has recently come to the fore as a prevalent social issue all over the world. The case of the Korean Society is not an exception in the world-wide phenomenon. However, there are two distinct differences in Korea as compared with other countries. One of the major differences is the inten- sity of aging as a result of a very low fertility rate (1.23 for Korea in 2010, 1.87 for France, 2.07 for U.S. 1.37 for Japan). According to the official pop- ulation projections 1) , the elderly population (defined as 65 and older) will reach 14% (aged society) of the national population in 2018, only 18 years after it first exceeded 7% (aging society) in 2000. It took France 115 years and the U.S. 73 years to go from an aging society to an aged society; it took Japan 26 years for this change. The other major difference is that Korea has a traditional custom where adult children live with and support their old parents. As a result, despite the rapid population aging, the asso- ciated problems with population aging have not been frequently observed and consequently, the issue of aging has not received enough attention from the