165 resultados para Difference-in-differences
em Queensland University of Technology - ePrints Archive
Resumo:
Using American panel data from the National Education Longitudinal Study of 1988, this article investigates the effect of working during grade 12 on attainment.We employ, for the first time in the related literature, a semiparametric propensity score matching approach combined with difference-in-differences. We address selection on both observables and unobservables associated with part-time work decisions, without the need for instrumental variable. Once such factors are controlled for, little to no effects on reading and math scores are found. Overall, our results therefore suggest a negligible academic cost from part-time working by the end of high school.
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Background: National physical activity data suggest that there is a considerable difference in physical activity levels of US and Australian adults. Although different surveys (Active Australia and BRFSS) are used, the questions are similar. Different protocols, however, are used to estimate “activity” from the data collected. The primary aim of this study was to assess whether the 2 approaches to the management of PA data could explain some of the difference in prevalence estimates derived from the two national surveys. Methods: Secondary data analysis of the most recent AA survey (N = 2987). Results: 15% of the sample was defined as “active” using Australian criteria but as “inactive” using the BRFSS protocol, even though weekly energy expenditure was commensurate with meeting current guidelines. Younger respondents (age < 45 y) were more likely to be “misclassified” using the BRFSS criteria. Conclusions: The prevalence of activity in Australia and the US appears to be more similar than we had previously thought.
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It is often reported that females lose less body weight than males do in response to exercise. These differences are suggested to be a result of females exhibiting a stronger defense of body fat and a greater compensatory appetite response to exercise than males do. Purpose This study aimed to compare the effect of a 12-wk supervised exercise program on body weight, body composition, appetite, and energy intake in males and females. Methods A total of 107 overweight and obese adults (males = 35, premenopausal females = 72, BMI = 31.4 ± 4.2 kg·m−2, age = 40.9 ± 9.2 yr) completed a supervised 12-wk exercise program expending approximately 10.5 MJ·wk−1 at 70% HRmax. Body composition, energy intake, appetite ratings, RMR, and cardiovascular fitness were measured at weeks 0 and 12. Results The 12-wk exercise program led to significant reductions in body mass (males [M] = −3.03 ± 3.4 kg and females [F] = −2.28 ± 3.1 kg), fat mass (M = −3.14 ± 3.7 kg and F = −3.01 ± 3.0 kg), and percent body fat (M = −2.45% ± 3.3% and F = −2.45% ± 2.2%; all P < 0.0001), but there were no sex-based differences (P > 0.05). There were no significant changes in daily energy intake in males or females after the exercise intervention compared with baseline (M = 199.2 ± 2418.1 kJ and F = −131.6 ± 1912.0 kJ, P > 0.05). Fasting hunger levels significantly increased after the intervention compared with baseline values (M = 11.0 ± 21.1 min and F = 14.0 ± 22.9 mm, P < 0.0001), but there were no differences between males and females (P > 0.05). The exercise also improved satiety responses to an individualized fixed-energy breakfast (P < 0.0001). This was comparable in males and females. Conclusions Males and premenopausal females did not differ in their response to a 12-wk exercise intervention and achieved similar reductions in body fat. When exercise interventions are supervised and energy expenditure is controlled, there are no sex-based differences in the measured compensatory response to exercise.
Resumo:
Over the years, public health in relation to Australian Aboriginal people has involved many individuals and groups including health professionals, governments, politicians, special interest groups and corporate organisations. Since colonisation commenced until the1980s, public health relating to Aboriginal and Torres Strait Islander people was not necessarily in the best interests of Aboriginal and Torres Strait Islander people, but rather in the interests of the non-Aboriginal population. The attention that was paid focussed more generally around the subject of reproduction and issues of prostitution, exploitation, abuse and venereal diseases (Kidd, 1997). Since the late 1980s there has been a shift in the broader public health agenda (see Baum, 1998) along with public health in relation to Aboriginal and Torres Strait Islander people (NHMRC, 2003). This has been coupled with increasing calls to develop appropriate tertiary curriculum and to educate, train, and employ more Aboriginal and Torres Strait Islander and non-Aboriginal people in public health (Anderson et al., 2004; Genat, 2007; PHERP, 2008a, 2008b). Aboriginal and Torres Strait Islander people have been engaged in public health in ways in which they are in a position to influence the public health agenda (Anderson 2004; 2008; Anderson et al., 2004; NATSIHC, 2003). There have been numerous projects, programs and strategies that have sought to develop the Aboriginal and Torres Strait Islander Public Health workforce (AHMAC, 2002; Oldenburg et al., 2005; SCATSIH, 2002). In recent times the Aboriginal community controlled health sector has joined forces with other peak bodies and governments to find solutions and strategies to improve the health outcomes of Aboriginal and Torres Strait Islander peoples (NACCHO & Oxfam, 2007). This case study chapter will not address these broader activities. Instead it will explore the activities and roles of staff within the Public Health and Research Unit (PHRU) at the Victorian Aboriginal Community Controlled Health Organisation (VACCHO). It will focus on their experiences with education institutions, their work in public health and their thoughts on gaps and where improvements can be made in public health, research and education. What will be demonstrated is the diversity of education qualifications and experience. What will also be reflected is how people work within public health on a daily basis to enact change for equity in health and contribute to the improvement of future health outcomes of the Victorian Aboriginal community.
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This study examined the distribution of major mosquito species and their roles in the transmission of Ross River virus (RRV) infection for coastline and inland areas in Brisbane, Australia (27°28′ S, 153°2′ E). We obtained data on the monthly counts of RRV cases in Brisbane between November 1998 and December 2001 by statistical local areas from the Queensland Department of Health and the monthly mosquito abundance from the Brisbane City Council. Correlation analysis was used to assess the pairwise relationships between mosquito density and the incidence of RRV disease. This study showed that the mosquito abundance of Aedes vigilax (Skuse), Culex annulirostris (Skuse), and Aedes vittiger (Skuse) were significantly associated with the monthly incidence of RRV in the coastline area, whereas Aedes vigilax, Culex annulirostris, and Aedes notoscriptus (Skuse) were significantly associated with the monthly incidence of RRV in the inland area. The results of the classification and regression tree (CART) analysis show that both occurrence and incidence of RRV were influenced by interactions between species in both coastal and inland regions. We found that there was an 89% chance for an occurrence of RRV if the abundance of Ae. vigifax was between 64 and 90 in the coastline region. There was an 80% chance for an occurrence of RRV if the density of Cx. annulirostris was between 53 and 74 in the inland area. The results of this study may have applications as a decision support tool in planning disease control of RRV and other mosquito-borne diseases.
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In language learning, listening is the basic skill which learners should begin to develop other skills, namely speaking, reading and writing. This sequence of language learning in most English as Foreign Language (EFL) settings goes against the stream, learning first reading and writing and later listening and speaking. This study investigates the effects of cognitive, process-based approach to instructing EFL listening strategies over 11 weeks during a semester in Persian (L1). Lower intermediate female participants (N = 50) came from a couple of EFL classrooms in an English Language Institute in Iran. The experimental group (n = 25) listened to their classroom activities using a methodology that led learners through four cognitive processes (guessing, making inference, identifying topics and repetition) in Persian was basically successful in EFL listening. The same teacher taught the control group (n = 25), which listened to the same classroom listening activities without any guided attention to the learning strategy process in Persian. A pre and post listening test made by a group of experts in the language institute tracked any development in light of cognitive learning strategy instruction in EFL listening through L1. The hypothesis was that the experimental group received the guided attention in L1 during the classroom listening activities made greater gains and was verified despite the partial improvement of the control group.
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This series of research vignettes is aimed at sharing current and interesting findings from our team of international Entrepreneurship researchers. In this vignette, Dr Henri Burgers considers some of the factors that can make a difference in managing new product development.
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The 1st July 1997 heralded the implementation of a number of amendments to the Queensland Criminal Code including some intriguing changes affecting the principal property offences of stealing (section 398) and dishonest application (section 408C). This article discusses the impact of the changes. It examines the extent of the amendments and then aims to delineate the ambit of each offence drawing on some of the more recent judgments in the area. It concludes that the offences are moving closer together while retaining many of the complexities of proof experienced in the past.
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Cervical auscultation (CA) may be used to complement the clinical feeding examination when assessing for oropharyngeal aspiration (OPA). Data exists on the acoustic properties of normal and abnormal swallowing sounds in adults and children. However, there are no published paediatric studies comparing the acoustic properties of sounds comparing OPA with non-OPA swallows. We aimed to determine if there is an acoustic difference between modified barium swallow (MBS)-identified OPA and non-OPA swallow sounds in children.
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This study investigates the impact floods on property values using the hedonic property price approach and other relevant econometric techniques. The main objectives of this research are to investigate (1) the impact of the release of flood-risk information and the actual floods on property values (2) the temporal behaviour of negative impacts (3) the property submarket behaviour (4) the behaviour of flood affected vs flood non-affected areas and (5) the property market efficiency. The thesis expanded on the existing literature on natural disasters by applying a range of econometric techniques. Findings of this research are useful for policy decision-making which is aimed at minimizing the negative impacts of natural hazards on property markets. The thesis findings also provide a better framework for decision-making in the property insurance market. The methodological improvements that are made in the thesis will be invaluable for analysing the impacts of natural hazards elsewhere.
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BACKGROUND: Indigenous patients with acute coronary syndromes represent a high-risk group. There are however few contemporary datasets addressing differences in the presentation and management of Indigenous and non-Indigenous patients with chest pain. METHODS: The Heart Protection Project, is a multicentre retrospective audit of consecutive medical records from patients presenting with chest pain. Patients were identified as Indigenous or non-Indigenous, and time to presentation and cardiac investigations as well as rates of cardiac investigations and procedures were compared between the two groups. RESULTS: Of the 2380 patients included, 199 (8.4%) identified as Indigenous, and 2174 (91.6%) as non-Indigenous. Indigenous patients were younger, had higher rates hyperlipidaemia, diabetes, smoking, known coronary artery disease and a lower rate of prior PCI; and were significantly less likely to have private health insurance, be admitted to an interventional facility or to have a cardiologist as primary physician. Following adjustment for difference in baseline characteristics, Indigenous patients had comparable rates of cardiac investigations and delay times to presentation and investigations. CONCLUSIONS: Although the Indigenous population was identified as a high-risk group, in this analysis of selected Australian hospitals there were no significant differences in treatment or management of Indigenous patients in comparison to non-Indigenous.
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Women are underrepresented in science, technology, engineering and mathematics (STEM) university coursework, reflecting long-standing gender issues that have existed in core middle-school STEM subject areas. Using data from a survey and written responses, we report on findings following the introduction of engineering education in middle school classes across three schools (grade level 7, n=122). The engineering experiences fused science, technology and mathematics concepts. The survey revealed higher percentages for girls than boys in 13 of the 24 items; however there were six items with a 20% difference in their perceptions about learning in STEM. For instance, despite girls recording that they have been provided equal or more opportunities than boys in STEM, they believed they do not do as well as boys (80% boys, 48% girls) or want to seek a career in STEM (39% boys, 17% girls). The written responses revealed gender differences across a number of themes in the students’ responses, including resources, group work, the nature and type of learning experiences, content knowledge, and teachers’ instructional style. Exposing students to STEM education facilitates an awareness of their learning and may assist girls to consider studying STEM subjects or STEM careers.