计量经济分析 = Econometric analysis

A growing body of evidence suggests that most adults exposed to potentially traumatic events are resilient. However, research on the factors that may promote or deter adult resilience has been limited. This study examined patterns of association between resilience and various sociocontextual factors. The authors used data from a random-digit-dial phone survey (N = 2,752) conducted in the New York City area after the September 11, 2001, terrorist attack. Resilience was defined as having 1 or 0 posttraumatic stress disorder symptoms and as being associated with low levels of depression and substance use. Multivariate analyses indicated that the prevalence of resilience was uniquely predicted by participant gender, age, race/ethnicity, education, level of trauma exposure, income change, social support, frequency of chronic disease, and recent and past life stressors. Implications for future research and intervention are discussed.

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What predicts psychological resilience after disaster? The role of demographics, resources, and life stress.

Minimum Design Loads for Buildings and Other Structures provides requirements for general structural design and includes means for determining dead, live, soil, flood, wind, snow, rain, atmospheric ice, and earthquake loads, as well as their combinations, which are suitable for inclusion in building codes and other documents. This Standard, a revision of ASCE/SEI 7-05, offers a complete update and reorganization of the wind load provisions, expanding them from one chapter into six. The Standard contains new ultimate event wind maps with corresponding reductions in load factors, so that the loads are not affected, and updates the seismic loads with new risk-targeted seismic maps. The snow, live, and atmospheric icing provisions are updated as well. In addition, the Standard includes a detailed Commentary with explanatory and supplementary information designed to assist building code committees and regulatory authorities. Standard ASCE/SEI 7 is an integral part of building codes in the United States. Many of the load provisions are substantially adopted by reference in the International Building Code and the NFPA 5000 Building Construction and Safety Code. Structural engineers, architects, and those engaged in preparing and administering local building codes will find this Standard an essential reference in their practice. Note: New orders are fulfilled from the second printing, which incorporates the errata to the first printing.

Minimum Design Loads for Buildings and Other Structures

There is increasing policy and research interest in disaster resilience, yet the extant literature is still mired in definitional debates, epistemological orientations of researchers, and differences in basic approaches to measurement. As a consequence, there is little integration across domains and disciplines on community resilience assessment, its driving forces, and geographic variability. Using US counties as the study unit, this paper creates an empirically-based resilience metric called the Baseline Resilience Indicators for Communities (BRIC) that is both conceptually and theoretically sound, yet, easy enough to compute for use in a policy context. A common set of variables were used to measure the inherent resilience of counties in the United States according to six different domains or capitals as identified in the extant literature – social, economic, housing and infrastructure, institutional, community, and environmental. Data were from public and freely accessible data sources. Counties in the US Midwest and Great Plains states have the most inherent resilience, while counties in the west, along the US-Mexico border, and along the Appalachian ridge in the east contain the least resilience. Further, it was found that inherent resilience is not the opposite of social vulnerability, but a distinctly different construct both conceptually and empirically. While understanding the overall variability in resilience, the BRIC is easily deconstructed to its component parts to provide guidance to policy makers on where investments in intervention strategies may make a difference in the improvement of scores. Such evidence-based research has an opportunity to influence public policy focused on disaster risk.

The geographies of community disaster resilience

A tipping point occurs when an external forcing causes a qualitative change in a system. Human-induced climate change could push several large elements of the climate system, such as the Greenland ice sheet, past a tipping point. Given the severity of the potential impacts, early warning of these changes would be advantageous. This Review discusses the most promising approaches to early warning of tipping points.

Early warning of climate tipping points

This paper extends prior research on the societal value of tornado warnings to the impact of false alarms. Intuition and theory suggest that false alarms will reduce the response to warnings, yet little evidence of a “false alarm effect” has been unearthed. This paper exploits differences in the false-alarm ratio across the United States to test for a false-alarm effect in a regression model of tornado casualties from 1986 to 2004. A statistically significant and large false-alarm effect is found: tornadoes that occur in an area with a higher false-alarm ratio kill and injure more people, everything else being constant. The effect is consistent across false-alarm ratios defined over different geographies and time intervals. A one-standard-deviation increase in the false-alarm ratio increases expected fatalities by between 12% and 29% and increases expected injuries by between 14% and 32%. The reduction in the national tornado false-alarm ratio over the period reduced fatalities by 4%–11% and inju...

False Alarms, Tornado Warnings, and Tornado Casualties

The impact of the installation of Weather Surveillance Radar-1988 Doppler (WSR-88D) radars in the 1990s on the quality of tornado warnings and occurrence of tornado casualties is examined. This analysis employs a dataset of tornadoes in the contiguous United States between 1986 and 1999. The date of WSR-88D radar installation in each National Weather Service Weather Forecast Office is used to divide the sample. Tornado warnings improved after the installation of Doppler radar; the percentage of tornadoes warned for increased from 35% before WSR-88D installation to 60% after installation while the mean lead time on warnings increased from 5.3 to 9.5 min and the false alarm ratio fell slightly. A regression analysis of tornado casualties, which controls for the characteristics of a tornado and its path, reveals that expected fatalities and expected injuries were 45% and 40% lower for tornadoes occurring after WSR-88D radar was installed in the NWS Weather Forecast Office. This analysis also finds that expected casualties are significantly lower for tornadoes occurring during the day or evening than late at night throughout the sample, which provides indirect evidence of the life-saving effects of tornado warnings.

WSR-88D Radar, Tornado Warnings, and Tornado Casualties

For almost a decade, economists Kevin M. Simmons and Daniel Sutter have been studying the economic impacts and social consequences of the approximately 1,200 tornadoes that touch down across the United States annually. During this time, Simmons and Sutter have been compiling information from sources such as the National Oceanic and Atmospheric Administration and the U.S. Census in order to examine the casualties caused by tornadoes and to evaluate the National Weather Service's efforts to reduce these casualties. In "Economic and Societal Impacts of Tornadoes", Simmons and Sutter present their findings. This analysis will be extremely useful to anyone studying meteorology and imperative for anyone working in emergency disaster management.

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Economic and Societal Impacts of Tornadoes

Conventional wisdom holds that improved tornado warnings will reduce tornado casualties, because longer lead times on warnings provide extra opportunities to alert residents who can then take precautions. The relationship between warnings and casualties is examined using a dataset of tornadoes in the contiguous United States between 1986 and 2002. Two questions are examined: Does a warning issued on a tornado reduce the resulting number of fatalities and injuries? Do longer lead times reduce casualties? It is found that warnings have had a significant and consistent effect on tornado injuries, with a reduction of over 40% at some lead time intervals. The results for fatalities are mixed. An increase in lead time up to about 15 min reduces fatalities, while lead times longer than 15 min increase fatalities compared with no warning. The fatality results beyond 15 min, however, depend on five killer tornadoes and consequently are not robust.

Tornado Warnings, Lead Times, and Tornado Casualties: An Empirical Investigation

1. Introduction Insurance companies have been hit hard in the last few years by claims from policyholders because of weather-related hazards such as floods and windstorms. Insured losses from Hurricane Andrew approached $16 billion (IIPLR 1995). However, estimates of potential damage for a storm like Andrew increase to $50 billion if the storm had hit Miami directly. These losses have prompted insurance companies, as well as state insurance boards, to explore incentives to property owners to install better protection for their property and demand construction techniques that minimize damage from storms. The Federal Emergency Management Agency (FEMA) has recently initiated programs to encourage voluntary mitigation by individuals as well as communities. The general consensus by disaster experts has been that home owners will not voluntarily adopt disaster mitigation measures.1 An early paper by Ehrlich and Becker (1972) (hereafter EB) provides a theoretical basis for evaluating mitigation decisions. The authors distinguish between two forms of mitigation: self-insurance and self-protection. The difference between these two terms is subtle but important. A self-insurance type of mitigation investment reduces the damage from a disaster but does not affect the probability of the disaster. In contrast, a selfprotection type of mitigation investment reduces the probability that the disaster will occur. Previous hedonic studies of household disaster mitigation, including those cited in this paper, have focused on self-protection. The agent is willing to pay more for a home that is located in a less dangerous area with lower associated probability of a hit. EB show that market insurance and self-insurance logically serve as substitutes. When market insurance is offered at an actuarially fair rate, there is no financial incentive to adopt self-insurance.2 Fronstin and Holtmann (1994, p. 388) provide evidence that supports this hypothesis. By examining the pattern of damage due to Hurricane Andrew, they find that newer homes suffered proportionately more damage than older homes. As an explanation of their findings, they hypothesize that "consumers have substituted homeowners insurance for structurally sound homes that are built to withstand hurricanes." Our study focuses on the value of a self-insurance type of mitigation in a location with a given historical probability of the disaster. The purpose of this study is to examine market price sensitivity of buyers to mitigation on existing homes. This information can assist policymakers in identifying effective incentives and provide necessary information to buyers in terms of the risk inherent with one property versus another. Our goal is to examine resale market price effects of voluntary mitigation measures taken by home owners to protect their property using market price data from a coastal city that is vulnerable to tropical storms and hurricanes. This paper is organized as follows. A short review of the relevant literature is outlined in the next section. This is followed by a description of our data set and the construction of a wind engineering-based structural integrity index. Next we specify the two models to be tested, one model with storm blinds as the mitigation focus variable and the second a construction index model that uses the structural integrity index. We then report results for both models and finish with conclusions and proposed extensions. 2. Review of Literature In a classic paper, EB examine a static model of insurance demand using a state preference approach. They consider market insurance and two forms of risk mitigation. Mitigation efforts can reduce the size of the loss or reduce the probability of the loss. The form that they call self-insurance reduces the size of a loss. Reducing the probability of the loss is referred to as self-protection. Some key results are the following: (i) The incentive to self-insure (loss-reducing mitigation), "unlike the incentive to use market insurance, is smaller for rare losses. …

Kevin M. Simmons

Papers

False Alarms, Tornado Warnings, and Tornado Casualties

WSR-88D Radar, Tornado Warnings, and Tornado Casualties

Economic and Societal Impacts of Tornadoes

Tornado Warnings, Lead Times, and Tornado Casualties: An Empirical Investigation

Valuing Mitigation: Real Estate Market Responses to Hurricane Loss Reduction Measures