Evaluation of free to grow: head start partnerships to promote substance-free communities

Free to Grow: Head Start Partnerships to Promote Substance-free Communities (FTG) was a national initiative in which local Head Start (HS) agencies, in partnership with other community organizations, implemented a mix of evidence-based family-strengthening and community-strengthening strategies. The evaluation of FTG used a quasi-experimental design to compare 14 communities that participated in the FTG intervention with 14 matched comparison communities. Telephone surveys were conducted with two cohorts of the primary caregivers of children in HS at baseline and then annually for 2 years. The survey was also administered to repeated cross-sectional samples of primary caregivers of young children who were not enrolled in HS. No consistent evidence was found in changes in family functioning or neighborhood conditions when the 14 FTG sites were compared to 14 matched sites. However, caregivers of young children who were not in HS in three high-implementing FTG sites showed evidence of improvements in neighborhood organization, neighborhood norms against substance abuse, and child disciplinary practices. Results provide highly limited support for the concept that family and neighborhood conditions that are likely to affect child development and well-being can be changed through organized efforts implemented by local HS programs.     

Bahadur efficiency of the F-test

Extremal problems in large deviations of the F-statistic are considered. It is shown that the slowest rate of convergence over a specified class of distributions of the F-statistic is slower than exponential, and that the Bahadur efficiency of the F-statistic with respect to some distribution-free competitors is identically zero.     

Book reviews

Many Thousands Gone: The First Two Centuries of Slavery in North America. Ira Berlin. Cambridge, MA: Harvard University Press. 1998. x, 497pp. $29.95. ISBN 0–674–81092–9.

More than Chattel: Black Women and Slavery in the Americas. Edited by David Barry Gaspar and Darlene Clark Hine. Bloomington and Indianapolis: Indiana University Press, 1996. xi, 341 pp. £14.99 (paper). ISBN 0–253–21043–7.

From Slavery to Freedom: Comparative Studies in the Rise and Fall of Atlantic Slavery. Seymour drescher. Foreword by Stanley L. Engerman. London: Macmillan. 1999. xxv, 454pp. £55.00. ISBN 0–333–73748–2.

Stylin’: African American Expressive Culture from its Beginnings to the Zoot Suit. Shane White and Graham White. Ithaca and London: Cornell University Press. 1998. xv. 301pp. £23.95 (cloth). ISBN 0–80143179–4.

Raising Cain: Blackface Performance from Jim Crow to Hip Hop. W. T. Lhamon, Jr. Cambridge, MA, and London: Harvard University Press. 1998. 269pp. $25.95 (cloth). ISBN 0–674–74711–9.

Restless Visionaries: The Social Roots of Antebellum Reform in Alabama and Michigan. John W. Quist. Baton Rouge: Louisiana State University Press. 1998. xi, 562pp. £45.90. ISBN 0–8071–2133–9.

Frccdpeople in the Tobacco South: Virginia, 1860–1900. Jeffrey R. Kerr‐Ritchie. Chapel Hill, NC: University of North Carolina press. 1999. xv, 345 pp. $49.95 (cloth); $18.95 (paper). ISBN 0–8078–2460–7; 0–8078–4763–1.

The Freedmen's Bureau and Black Texans. Barry A. Crouch. Austin: University of Texas at Austin Press. 1999. xix, 187pp. $12.95 (paper). ISBN 0–292–71219–7.

Montpelier, Jamaica: A Plantation Community in Slavery and Freedom, 1739–1912. B.W. Higman. Kingston: The Press University of the West Indies. 1998. xv, 384pp. £20.00/$35.00. ISBN 976–640–039–3.

In Place of Slavery: A Social History of British Indian and Javanese Laborers in Suriname. Rosemarijn Hoefte. Gainsville: University of Florida Press. 1998. xii, 275pp. $49.95. ISBN 0–8130–1625–8.

Writing West Indian Histories. B.W. Higman. London and Basingstoke: Macmillan Education. 1999. xiv, 289 pp. £15.50 (paper). ISBN 0–333–73296–0.

Free and Unfree Labour: The Debate Continues. Edited by Tom Brass and Marcel Van Der Linden. Bern/Berlin/Frankfurt a.M: Peter Lang. 1997 (International and Comparative Social History 5). 602 pp. £52.00. ISBN 3–906756–87–4.

Servicing the Master. Slavery and Society in Nineteenth Century Morocco. Mohammed Ennaji. Translated by Seth Graebner. London: Macmillan, 1999. xix, 166pp. £35.00. ISBN 0–333–75477–8.

Servants of Allah. Sylviane A. Diouf. New York: New York University Press. 1998. vii, 254 pp. $18.50. ISBN 0–8147–1905–8     

Stochastic Measures of Network Resilience: Applications to Waterway Commodity Flows

Given the ubiquitous nature of infrastructure networks in today's society, there is a global need to understand, quantify, and plan for the resilience of these networks to disruptions. This work defines network resilience along dimensions of reliability, vulnerability, survivability, and recoverability, and quantifies network resilience as a function of component and network performance. The treatment of vulnerability and recoverability as random variables leads to stochastic measures of resilience, including time to total system restoration, time to full system service resilience, and time to a specific α% resilience. Ultimately, a means to optimize network resilience strategies is discussed, primarily through an adaption of the Copeland Score for nonparametric stochastic ranking. The measures of resilience and optimization techniques are applied to inland waterway networks, an important mode in the larger multimodal transportation network upon which we rely for the flow of commodities. We provide a case study analyzing and planning for the resilience of commodity flows along the Mississippi River Navigation System to illustrate the usefulness of the proposed metrics.     

Risk of Norovirus Gastroenteritis from Consumption of Vegetables Irrigated with Highly Treated Municipal Wastewater—Evaluation of Methods to Estimate Sewage Quality

Quantitative microbial risk assessment was used to assess the risk of norovirus gastroenteritis associated with consumption of raw vegetables irrigated with highly treated municipal wastewater, using Melbourne, Australia as an example. In the absence of local norovirus concentrations, three methods were developed: (1) published concentrations of norovirus in raw sewage, (2) an epidemiological method using Melbourne prevalence of norovirus, and (3) an adjustment of method 1 to account for prevalence of norovirus. The methods produced highly variable results with estimates of norovirus concentrations in raw sewage ranging from 10⁴ per milliliter to 10⁷ per milliliter and treated effluent from 1 × 10^?3 per milliliter to 3 per milliliter (95th percentiles). Annual disease burden was very low using method 1, from 4 to 5 log₁₀ disability adjusted life years (DALYs) below the 10^?6 threshold (0.005–0.1 illnesses per year). Results of method 2 were higher, with some scenarios exceeding the threshold by up to 2 log₁₀ DALYs (up to 95,000 illnesses per year). Method 3, thought to be most representative of Melbourne conditions, predicted annual disease burdens >2 log₁₀ DALYs lower than the threshold (～4 additional cases per year). Sensitivity analyses demonstrated that input parameters used to estimate norovirus concentration accounted for much of the model output variability. This model, while constrained by a lack of knowledge of sewage concentrations, used the best available information and sound logic. Results suggest that current wastewater reuse behaviors in Melbourne are unlikely to cause norovirus risks in excess of the annual DALY health target.     

Advice to Risk Assessors Modeling Viral Health Risk Associated with Household Graywater

Quantitative microbial risk assessment (QMRA) is a valuable tool that can be used to predict the risk associated with human exposure to specific microbial contaminants in water sources. The transparency inherent in the QMRA process benefits discussions between multidisciplinary teams because members of such teams have different expertise and their confidence in the risk assessment output will depend upon whether they regard the selected input data and assumptions as being suitable and/or plausible. Selection of input data requires knowledge of the availability of appropriate data sets, the limitations of using a particular data set, and the logic of using alternative approaches. In performing QMRA modeling and in the absence of directly relevant data, compromises must be made. One such compromise made is to use available Escherichia coli data and apply a ratio of enteric viruses to indicator E. coli in wastewater obtained from prior studies to estimate the concentration of enteric viruses in other wastewater types/sources. In this article, we have provided an argument for why we do not recommend the use of a pathogen to E. coli ratio to estimate virus concentrations in single household graywater and additionally suggested circumstances in which use of such a ratio may be justified.     

Development of demand pull type control methods: The design of block action production control methods to reduce throughput time and improve supply chain synchronization

In this paper the implementation of time based manufacturing strategies and pull type control systems in an organization manufacturing electrical switchgear built to customers individual requirements are discussed in detail. The concept of block control to synchronize the production time of all internally and externally sourced components and materials is also introduced in an attempt to simplify production control methods and reduce throughput time. Savings in time and cost are described during a twenty months period of restructuring. Foundations were laid for a second objective which is an attempt to gain some linkage between throughput time reduction and resultant production costs.     

Allocating observations in a test for the ratio of scales of independent gamma variates

Consider two independent gamma populations with common shape parameter α. Let ρ denote the ratio of their scale parameters, and consider the problem of testing the null hypothesis ρ = 1 against the alternative ρ = 1 + r , where r >0 . A procedure, not depending on α , that maximizes the exact slope at this alternative is proposed.