Confidence Intervals for the Weighted Sum of Two Independent Binomial Proportions

Confidence intervals for the difference of two binomial proportions are well known, however, confidence intervals for the weighted sum of two binomial proportions are less studied. We develop and compare seven methods for constructing confidence intervals for the weighted sum of two independent binomial proportions. The interval estimates are constructed by inverting the Wald test, the score test and the Likelihood ratio test. The weights can be negative, so our results generalize those for the difference between two independent proportions. We provide a numerical study that shows that these confidence intervals based on large‐sample approximations perform very well, even when a relatively small amount of data is available. The intervals based on the inversion of the score test showed the best performance. Finally, we show that as for the difference of two binomial proportions, adding four pseudo‐outcomes to the Wald interval for the weighted sum of two binomial proportions improves its coverage significantly, and we provide a justification for this correction.     

Land-cover fragmentation and configuration of ownership parcels in an exurban landscape

The rate of low-density development beyond the urban and suburban periphery, known as exurban areas, has occurred at a rate faster than both urban and population growth and has the potential to affect water quality, carbon storage, and habitat availability. This paper is aimed at understanding the relationships between the heterogeneity of the human and natural components of the land system and their interactions, through assessment of residential land-cover characteristics and ownership parcels in these poorly understood exurban lands. New data are presented that describe the distribution of land-cover quantities and their degree of fragmentation in three townships in Southeastern Michigan. Analysis of land-cover data, collected from aerial photographs from 1950–2000 and digitized with a 10 m minimum mapping unit, provide an empirical link between lot-size and vegetation. Results show, among other findings, 1) the quantity and pattern of land-cover types significantly differ with parcel size, 2) the degree of difference was greatest between small parcels and all other sizes and least among large parcels, and 3) of five landscape metrics used to evaluate the quantity and fragmentation of land-cover types in residential parcels, the percent of parcel area provided the strongest delineation of differences in land cover among parcel sizes. Capturing quantities and patterns of land-cover at different sizes of land (parcel) ownership provide new data that can be coupled to ecosystem literature and models to link the outcomes of residential land-cover processes with simple ecosystem functions (e.g. carbon storage, albedo). Understanding how residential land-use and management processes collectively create regional land-cover patterns can provide insight into how residential lands might be managed to mitigate the effects of land change on climate.     

Linguistic Labels and Categorization in Infancy: Do Labels Facilitate or Hinder?

Although it is generally accepted that labels facilitate categorization in infancy, recent evidence suggests that infants and young children are more likely to process visual input when presented in isolation than when paired with nonlinguistic sounds or linguistic labels. These findings suggest that auditory input (when compared to a no‐auditory baseline) may hinder rather than facilitate categorization. This study assessed 8‐month‐olds' (n = 191) and 12‐month‐olds' (n = 81) abilities to form categories when images were paired with nonlinguistic sounds, linguistic labels, and when presented in isolation. Overall, infants accumulated more looking when visual stimuli were accompanied by sounds or labels; however, infants were more likely to categorize when the visual images were presented without an auditory stimulus.     

Language Diversity and Accountability in the South: Perspectives and Dilemmas

This paper examines the need for accountability in language planning in multilingual contexts in the South. After a brief overview of language diversity in the South, it notes that this multilingual reality has often been ignored by policy-makers acting in their own interests, unaccountable to those affected by their decisions. It considers how world trends of increasing democratisation and strengthening of minority rights are generating calls for greater accountability and language rights, so that governments become more accountable to communities for their decisions about language. Some dimensions of accountability are explored, focussing on the need to integrate the perspectives of both government and community. Structures are addressed, with an emphasis on the role of local communities and illustrations from two particular African contexts, in Cameroon and Zaire. The paper concludes with a discussion of some practical dilemmas relating to policy and research, technical input, financial assistance and community ambivalence.     

Context,Diversity and Engagement: Early Intervention with Australian Aboriginal Families in Urban and Remote Contexts

This article describes challenges met implementing an early intervention programme for Aboriginal parents and their children in the NT (Northern Territory) of Australia in the context of efforts to remediate Aboriginal disadvantage. The intervention is an adaptation of an 8‐ to 10‐week, manualised parenting programme designed for four‐ to six‐year‐old children with behavioural difficulties. It was implemented for both Aboriginal and non‐Aboriginal children in urban Darwin and for Aboriginal children in three communities of the Tiwi Islands, near Darwin. Measured outcomes of the programme were positive overall with different outcomes by gender and Indigenous status. There were marked differences in retention of families from different socio‐cultural backgrounds in the programme, with a significant loss of participants from referral through commencement to six‐month follow‐up. This drop‐out was most marked for urban Aboriginal participants, despite highly flexible strategies of engagement and cultural adaptation of the approach pursued in each setting. The research provides lessons for the contextualisation of preventive interventions in diverse community settings and shows that systematic attention to cultural ‘fit’ of the intervention logic and cultural competence in engagement of disadvantaged families with multiple problems are fundamental to sustainability.     

Effects of a summer emergent literacy intervention for rising kindergarteners

This study examined the effectiveness of a nine-week summer emergent literacy program implemented in a Young Men's Christian Association (YMCA) summer program that serves families from low socioeconomic backgrounds. Participants were four- and five-year-old children attending a YMCA summer camp. After being placed in appropriate respective skill-level groups, children received one-hour, daily emergent literacy instruction from their camp counselors, who were trained as novice reading teachers. The teachers used emergent literacy activities to support letter-naming fluency and growth in letter-sound correspondence recognition in addition to mastery of read-aloud texts. The 28 participants experienced positive growth on both dependent measures (letter-naming fluency and letter-sound fluency), indicating the efficiency of the intervention as a tool for improving school readiness for children from low-income families. Additionally, the results suggest that beginning reading teachers may be able to conduct effective emergent literacy instruction, making the intervention replicable. Limitations and associated future research directions are discussed.     

Assessing human movement with accelerometry

The methods for measuring and evaluating human movement have advanced rapidly over the past 2 decades. The use of smaller, lighter, more powerful personal computers, digital video cameras and miniature, portable accelerometers have allowed the health professional, engineer, sports coach and scientist to very precisely record and quantify human movements on the sports field, in the business office, industrial setting and in the home. Most human motion analysis systems have evolved to meet the particular needs of the user. One such system that has developed over the past ten years in the Sport Science Laboratory at Dalhousie University is the Padlog series of accelerometer systems. This paper will discuss the development the Padlog systems at Dalhousie.     

Teaching Note—Teaching Intersectionality: Transforming Cultural Competence Content in Social Work Education

Intersectionality has been gaining momentum among social workers as a framework to allow a fuller understanding of the complexity of diverse social identities and the impact of social structures on power, privilege, and oppression. However, the application of intersectionality to teaching in social work education has been relatively absent in the literature. This article describes a 3-hour graduate-level classroom exercise designed to increase knowledge and proficiency of intersectionality. Critical self-reflections of the participants’ experiences are provided to illustrate the evolving growth and awareness that can result from the educational process using this framework. Examples and suggestions for reading assignments and classroom activities are offered. Implications for social work education and future directions are discussed.