We examined the relation of early life socioeconomic circumstances to cognition in older residents of a biracial urban community. Participants had brief cognitive testing three times at approximately 3-year intervals. At baseline, information about early life household and county socioeconomic level was collected. In mixed-effects models adjusted for age, sex, race, and education, both early life household and county socioeconomic levels were positively associated with baseline level of cognition but unrelated to cognitive decline. The results suggest that socioeconomic conditions in early life are associated with level of cognitive function in old age but not with rate of cognitive decline.

Comparative studies of occupational sex segregation have employed a variety of measures to estimate the extent of segregation across labor markets. In this article, the authors focus on two intrinsic limitations of the ratio index, which is derived from the log-linear framework: singularity for totally segregated occupations and sensitivity near the extremes. To capture the real essence of gender occupational segregation, it is necessary to examine rather detailed occupational categories. Such detailed occupational classification poses a problem for the ratio index since small occupations are more likely to be mono-gender occupations. The authors propose an alternative modified index that resolves both the singularity and the sensitivity problems by employing the "first-order approximation" of the logarithmic function. The modified index makes it possible to compute measures of microsegregation for detailed occupational categories. The advantages of the proposed index for comparative microsegregation analyses are illustrated and discussed.

In this report to the Mental Health Services Act Planning Counsel, we derive estimates of the number of youth and children in San Francisco who have unmet needs for mental health services. Estimates are based on the published prevalence of mental health conditions in other locales, which are applied to San Francisco using census microdata.

This essay provides an overview of current trade patterns between New England and China. It was prepared for a symposium sponsored by The Boston Athenaeum comparing New Englands present-day trade with China to the regions prominence in the U.S.-China trade of the 19th century. The essay concludes that a special trade relationship between New England and China does not exist at the present time. Although New Englands exports to China are growing rapidly, they are not growing markedly faster than exports from the rest of the country, and China does not account for an unusually large fraction of New Englands exports. Moreover, there is some indication that New England has felt the brunt of competition from Chinese imports more strongly than other regions. In one arena, New England does hold a special position: New England universities are highly regarded in China, and the regions share of Chinese students is above its population sharealthough in line with its share of foreign students generally.

This essay provides an overview of current trade patterns between New England and China. It was prepared for a symposium sponsored by The Boston Athenaeum comparing New Englands present-day trade with China to the regions prominence in the U.S.-China trade of the 19th century. The essay concludes that a special trade relationship between New England and China does not exist at the present time. Although New Englands exports to China are growing rapidly, they are not growing markedly faster than exports from the rest of the country, and China does not account for an unusually large fraction of New Englands exports. Moreover, there is some indication that New England has felt the brunt of competition from Chinese imports more strongly than other regions. In one arena, New England does hold a special position: New England universities are highly regarded in China, and the regions share of Chinese students is above its population sharealthough in line with its share of foreign students generally.

This report is based on interviews with 1,203 California households undertaken in 2001 for the California Integrated Waste Management Board (CIWMB)--Do-It-Yourself households (DIY) who change the oil of household vehicles, "shade-tree mechanics" (STM) who also change oil for others, and households that do not change their own oil--on oil collection data maintained by the CIWMB; and on PUMS data on households. The report presents estimates of rates of DIY and STM activity; the volume of oil and filters consumed and disposed by DIY households and STMs; and the rate and volume of their illegal disposal, for California, for counties, and for population groups. Curbside pickup is shown to reduce illegal disposal nearly to zero. DIYers who do not have curbside pickup (therefore have to take oil to a collection center if they recycle it at all) dispose illegally at a 66 percent rate--48 percent even if they regard the available centers as "very convenient." Making curbside pickup available to 90 percent of California households would collect much more of the now illegally disposed oil than making collection centers "very convenient" to every household in the state.Younger U.S.-born STMs are shown to dispose of far more oil illegally than any other group. Surveys tend to underestimate sensitive behavior such as illegal disposal. A mathematical model of the relationship between survey data on disposal and aggregate data on used oil collection was developed to yield much more accurate estimates of illegal disposal overall and for various kinds of households. Estimated parameters of total and illegal used oil disposal were estimated from the survey data by multivariate regression, then applied to PUMS data on households to estimate total and illegal disposal by county.The report includes analysis of the media reachability of DIYers, STMs, and illegal disposers.

This article provides an overview of gender inequality in labor markets in the United States. I show trends in labor force participation, occupational segregation, and the pay gap. Though my main focus is the United States, I note where similar findings exist for other affluent nations. I explain what we know from past research about the causes of inequality and note the gaps in our knowledge. In broad brush strokes, the sex gap in pay in the United States has two major sources: the segregation of jobs and the effects of womens responsibility for childrearing. My major thesis is that at least in the United States, these two are largely unrelated. That is, the causes of segregation do not seem to be largely about womens mothering responsibilities, and the penalties for motherhood do not appear to flow largely through segregation. This thesis is at odds with much thinking among economists, who have seen segregation as a rational response by employers and employees to gender differences in intermittence of employment. In this economic view, women choose more "mother-friendly" jobs, which maximize their earnings conditional on intermittent and flexible employment but tradeoff on-the-job training, higher earnings, and steeper wage trajectories to do so.

Exploratory rule discovery is widely employed in real-world data mining, because of the flexibility in selecting applicable models. Nevertheless, two problems coexist with the merits of exploratory rule discovery. One of these drawbacks is how to limit within reasonable bounds the number of resulting models. The other problem is how to improve the efficiency of rule discovery by eliminating unnecessary computation and I/O. Techniques for tackling these issues have been studied extensivelyin the context of exploratory rule discovery with qualitative attributes. However, databases processed often involve quantitative attributes. Some researchers strive to introduce quantitative attributes into exploratory rule discovery by discretization, with which information loss is unavoidable. Such techniques are not optimal for mining inter-relationships between quantitative attributes and qualitative attributes. A special class of exploratory rule discovery has been proposed for mining rules with consequents being one or more undiscretized target quantitative variables.Characteristics of the selected quantitative variables are described using distributional statistics. However, previous techniques for mining exploratory rules with undiscretized quantitative targets cannot efficiently search for rules in verylarge, dense databases. Rule pruning techniques in this context are also limited. The only investigation was the pruning of insignificant quantitative association rules proposed by Aumann and Lindell (1999). Efficiency is one of the critical issues for such techniques.Accordingly, we propose techniques for pruning rules with undiscretized quantitative attributes. We call these techniques the derivative extended rule filter and the derivative partial rule filter. The derivative extended rule filter is an efficientvariant of the existing insignificant quantitative association rule pruning proposed by Aumann and Lindell (1999). The derivative partial rule filter is able to remove potentially uninteresting rules that remain after the derivative extended rule filter is applied. We also discovered severe efficiency problems in existing rule pruningtechniques with undiscretized quantitative attributes. The triviality filter is then suggested as a complement for the derivative extended rule filter, whose antimonotonicity can be utilized for more powerful search space pruning. We also propose the difference set statistics derivation and the circular intersection approaches for lessening the redundancies of data accesses and computations in our original implementation of derivative rule filters. Detailed experimental evaluations are committed to back up our arguments for desirable performance expectations with the above techniques.

This paper examines the relationship between workforce demographics and ag-gregate productivity. Cross country regressions show changes in the age structure ofthe workforce to be signicantly correlated with changes in aggregate productivity.Dierent demographic structures may be related to almost one quarter of the persis-tent productivity gap between the OECD and low income nations. The magnitudeof these correlations is signicantly larger than one would expect from the privatereturn to experience, suggesting externalities. Causal mechanisms through inventiveactivity and management are suggested and evidence from the US census is shown tobe consistent with these mechanisms. Results using US state and metropolitan areadata suggest that the scope of the externality is largely national, not regional.

This paper examines the effect of state prepaid tuition programs on state support for higher education. Prepaid tuition programs are state programs that allow citizens to purchase future tuition credits at a fixed price. Twenty states now offer such programs, and investments in these programs are growing rapidly. Examining state panel data from 1990-2002 suggests that these plans are having some effect on state support for higher education. While states that initiate these plans initially show slightly greater support for higher education, where investment levels are higher states show less support for higher education. The paper concludes that the contribution these programs make to national higher education policy goals is in need of greater scrutiny.

We present a three-stage, nonparametric estimation procedure to recover willingness to pay for housing attributes. In the first stage we estimate a nonparametric hedonic home price function. In the second stage we recover each consumer's taste parameters for product characteristics using first-order conditions for utility maximization. Finally, in the third stage we estimate the distribution of household tastes as a function of household demographics. As an application of our methods, we compare alternative explanations for why blacks choose to live in center cities while whites suburbanize.

Fighting in the Streets provides a comparative analysis of some of the most severe episodes of urban unrest that took place in twentieth-century America, including the 1919 Chicago Riot, the 1943 Detroit Riot, the 1967 Newark and Detroit Riots, the 1980 Miami Riot, and the 1992 Los Angeles Riot. Examining the patterns of death and destruction of property that occurred during these events, as well as historical evidence regarding struggles for housing, jobs, and political power among members of different racial/ethnic groups, this book makes the case for a general explanatory model of urban unrest as a product of rapid demographic change. Focusing at the neighborhood level, where demographic changes have their greatest impact, Fighting in the Streets posits that riot-related violence is most likely to take place in neighborhoods characterized by high levels of black/white segregation, poverty, unemployment, and rapid population turnover. Such a "profile" of the riot-prone neighborhood may enable policy makers to avert future violence through targeted economic and political intervention, such as building community institutions that integrate newcomers and natives. This book is particularly suited for classes in urban studies, race/ethnic relations, and collective behavior/social movements as well as public policy and planning.

Governments often target redistributive policies to unproductive sectors. The traditional economic wisdom is that the government should buy out the agents in these sectors, giving them the same utility as under the redistributive policy, and letting them relocate to more productive sectors. Instead, governments often provide transfers that maintain factors of production in unproductive sectors. We show that these transfers may not be inefficient, if the agents that receive them have more correlated incomes than agents in other sectors. So it may be cheap for a government to give a certain level of utility to a group if it engages in an activity that, while inefficient, is subject to correlated individual shocks. Empirically, in the US, positive transfers seems to go with correlation in incomes.

Economic growth in the California's North Bay region since the 1980s has failed to bring shared prosperity to the region's residents. This report links demographic, industry, labor market, income and quality of life data in four counties--Sonoma, Marin, Napa and Mendocino--to reveal patterns of family income polarization and growing working poverty, with minorities disproportionately affected. These trends are anchored in labor market polarization over the past two decades and the current explosion in low-wage service jobs. The report suggests a range of state and local strategies to lift the wages and incomes of low-wage workers and their families, and expand access to basic needs (e.g., health care and housing).

Vietnamese, Laotian, and Cambodian Americans The past is never dead. It is not even past. In the quarter century following the end of the Indochina War in 1975, one and a half million refugees and immigrants from Vietnam, Laos, and Cambodia arrived in the United States. Together with their nearly half a million American-born children, by the year 2000 they already represented more than one out of every six Asian Americans, adding significantly not only to the size but to the diversity of the Asian-origin population in the U.S. They are the newest Asian Americans, and the story of their migration and incorporation in America differs fundamentally from that of other Asian-origin ethnic groups. To be sure, except for persons of Japanese descent, the overwhelming majority of Asian Americans today are foreign born, reflecting the central role of contemporary immigration in the formation of these ethnic groups. But unlike the ...