Changes in Household Hazard Adjustment in Los Angeles County over the Past Four Decades

This dissertation assessed the changes in household hazard adjustment from 1977 to 2008 and analyzed the reasons for the adjustments in order to determine whether the behavioral changes were motivated by earthquakes. Factors which influence the adoption of and motivation for hazard adjustment were also investigated. Los Angeles County experienced a notable racial/ethnic transition during the time in question. Hence, this dissertation examined the effect of the demographic transition on the change in hazard adjustment. Geographical differences in hazard adjustment and characteristics of the neighborhoods with low hazard adjustment were also identified.;Four cross-sectional datasets collected in 1977, 1988--1989, 1994--1996, and 2008 were analyzed. Hazard adjustment was measured by 11 activities, such as water storage, emergency-plan preparation, and latch installation to mitigate the impact of earthquakes. A total sample of 3,505 residents of Los Angeles County was analyzed. Weights were applied to account for disproportionate sampling associated with two of the four datasets.;The level of hazard adjustment increased after the 1988 Whittier Narrows and 1994 Northridge earthquakes, and it was sustained afterwards. However, households of Los Angeles County were still insufficiently prepared for disasters. Notably, very few households performed planning and mitigation activities. Although there were variations in the degree of influence by activity, homeownership and experiencing earthquake-related property damage contributed the most to the improvement in hazard adjustment. Households tended to do hazard-adjustment activities only for earthquakes in 1994--1996; in 2008, more households did these activities for both earthquakes and other reasons. The racial/ethnic transition did not have a significant effect on the change in preparedness. Yet, Blacks and Hispanics tend to live in neighborhoods with low hazard adjustment, low income, and high population density. Predominantly Hispanic neighborhoods have a high density of foreign-born residents with limited English proficiency.;This study showed that interventions should be tailored to communities based on neighborhood characteristics and the strengths and weaknesses of their preparedness. There is an urgent need for promoting culturally-sensitive preparedness education and trainings, and the establishment of emergency networks within official agencies and communities to ensure the efficacy in disaster response and recovery assistance.