Self-reported risk-taking behavior during matched-frequency sessions of alcohol versus combined alcohol and energy drinks consumption: Does co-ingestion increase risk-taking?

Background: Emerging evidence indicates that consumers of alcohol mixed with energy drink (AmED) self-report lower odds of risk-taking after consuming AmED versus alcohol alone. However, these studies have been criticized for failing to control for relative frequency of AmED versus alcohol-only consumption sessions. These studies also do not account for quantity of consumption and general alcohol-related risk-taking propensity. The aims of the present study were to (i) compare rates of risk-taking in AmED versus alcohol sessions among consumers with matched frequency of use and (ii) identify consumption and person characteristics associated with risk-taking behavior in AmED sessions. Methods: Data were extracted from 2 Australian community samples and 1 New Zealand community sample of AmED consumers (n = 1,291). One-fifth (21%; n = 273) reported matched frequency of AmED and alcohol use. Results: The majority (55%) of matched-frequency participants consumed AmED and alcohol monthly or less. The matched-frequency sample reported significantly lower odds of engaging in 18 of 25 assessed risk behaviors in AmED versus alcohol sessions. Similar rates of engagement were evident across session type for the remaining behaviors, the majority of which were low prevalence (reported by <15%). Regression modeling indicated that risk-taking in AmED sessions was primarily associated with risk-taking in alcohol sessions, with increased average energy drink (ED) intake associated with certain risk behaviors (e.g., being physically hurt, not using contraception, and driving while over the legal alcohol limit). Conclusions: Bivariate analyses from a matched-frequency sample align with past research showing lower odds of risk-taking behavior after AmED versus alcohol consumption for the same individuals. Multivariate analyses showed that risk-taking in alcohol sessions had the strongest association with risk-taking in AmED sessions. However, hypotheses of increased risk-taking post-AmED consumption were partly supported: Greater ED intake was associated with increased likelihood of specific behaviors, including drink-driving, sexual behavior, and aggressive behaviors in the matched-frequency sample after controlling for alcohol intake and risk-taking in alcohol sessions. These findings highlight the need to consider both personal characteristics and beverage effects in harm reduction strategies for AmED consumers.

Changing from primary to secondary school highlights opportunities for school environment interventions aiming to increase physical activity and reduce sedentary behaviour: a longitudinal cohort study.

BACKGROUND: There is little empirical evidence of the impact of transition from primary to secondary school on obesity-related risk behaviour. The purpose of this study was to examine the effect of a change of school system on physical activity (PA) and sedentary behaviour in pre-early adolescents. METHODS: Fifteen schools in Victoria, Australia were recruited at random from the bottom two strata of a five level socio-economic scale. In nine schools, students in year 6 primary school transitioned to a different school for year 7 secondary school, while in six schools (combined primary-secondary), students remained in the same school environment from year 6 to year 7. Time 1 (T1) measures were collected from students (N=245) in year 6 (age 11-13). Time 2 (T2) data were collected from 243 (99%) of the original student cohort when in year 7. PA and sedentary behaviour data were collected objectively (via ActiGraph accelerometer) and subjectively (via child self-report recall questionnaire). School environment data were collected via school staff survey. Change of behaviour analyses were conducted longitudinally i) for all students and ii) by change/no change of school. Mixed model regression analysis tested for behavioural interaction effects of changing/not changing school. RESULTS: Sixty-three percent (N=152) changed schools from T1 to T2. Across all students we observed declines in average daily moderate to vigorous physical activity (MVPA) (-4 min) and light PA (-23 min), and increases in average daily sedentary behaviour (16 min), weekday leisure screen time (17 min) and weekday homework screen time (25 min), all P<0.05. Compared to students who remained in the same school environment, students who changed school reported a greater reduction in PA intensity at recess and lunch, less likelihood to cycle to/from school, greater increase in weekday (41 mins) and weekend (45 mins) leisure screen time (P<0.05) and greater encouragement to participate in sport. School staff surveys identified that sport participation encouragement was greater in primary and combined primary-secondary than secondary schools (P<0.05). CONCLUSION: Transitioning from primary to secondary school negatively impacts on children's PA and sedentary behaviour, and has further compounding effects on behaviour type by changing school environments.

Does maternal psychopathology increase the risk of pre-schooler obesity? A systematic review

The preschool years may be a critical period for child obesity onset; however, literature examining obesity risk factors to date has largely focused on school-aged children. Several links have been made between maternal depression and childhood obesity risks; however, other types of maternal psychopathology have been widely neglected. The aim of the present review was to systematically identify articles that examined relationships between maternal psychopathology variables, including depressive and anxiety symptoms, self-esteem and body dissatisfaction, and risks for pre-schooler obesity, including weight outcomes, physical activity and sedentary behaviour levels, and nutrition/diet variables. Twenty articles meeting review criteria were identified. Results showed positive associations between maternal depressive symptoms and increased risks for pre-schooler obesity in the majority of studies. Results were inconsistent depending on the time at which depression was measured (i.e., antenatal, postnatal, in isolation or longitudinally). Anxiety and body dissatisfaction were only measured in single studies; however, both were linked to pre-schooler obesity risks; self-esteem was not measured by any studies. We concluded that maternal depressive symptoms are important to consider when assessing risks for obesity in preschool-aged children; however, more research is needed examining the impact of other facets of maternal psychopathology on obesity risk in pre-schoolers.

Prediction interval estimation of electricity prices using PSO-tuned support vector machines

Uncertainty of the electricity prices makes the task of accurate forecasting quite difficult for the electricity market participants. Prediction intervals (PIs) are statistical tools which quantify the uncertainty related to forecasts by estimating the ranges of the future electricity prices. Traditional approaches based on neural networks (NNs) generate PIs at the cost of high computational burden and doubtful assumptions about data distributions. In this work, we propose a novel technique that is not plagued with the above limitations and it generates high-quality PIs in a short time. The proposed method directly generates the lower and upper bounds of the future electricity prices using support vector machines (SVM). Optimal model parameters are obtained by the minimization of a modified PI-based objective function using a particle swarm optimization (PSO) technique. The efficiency of the proposed method is illustrated using data from Ontario, Pennsylvania-New Jersey-Maryland (PJM) interconnection day-ahead and real-time markets.

The role of rice in poverty dynamics in rural Vietnam: 2002–2008

Using the Vietnamese Household Living Standards Surveys of 2002, 2004, 2006, and 2008, this paper investigates the role of rice in poverty dynamics in the recent context of Vietnam. We find that sizeable changes in rice prices in the 2000s, which were driven largely by the country's integration into the world markets, have not helped rural households escape poverty, even for households with large-scale rice production. Our results also document that changes in rice output and productivity did not help mitigate poverty either. The paper provides evidence to explain why a substantial exogenous increase in the rice prices between 2006 and 2008 did not help rural households to move out of poverty, while similar changes did help in the 1990s.

Farmland prices, structural breaks and panel data

Previous time series evidence has indicated that farmland prices and cash rents are not cointegrated, a finding at odds with the present value model of farmland prices. We argue that this failure to find cointegration may be due to low power of tests and to the presence of structural change representing a shifting risk premium on farmland investments. To accommodate this possibility, we use panel unit root and cointegration methods that are more powerful than conventional time series methods and allow for breaks in the cointegration relationship. Our results, based on a large panel covering 31 US states between 1960 and 2000, suggest that the present value model of farmland prices cannot be rejected. © Oxford University Press and Foundation for the European Review of Agricultural Economics 2007; all rights reserved.

Eating locally: Australasian gannets increase their foraging effort in a restricted range

During the breeding season, seabirds adopt a central place foraging strategy and are restricted in their foraging range by the fasting ability of their partner/chick and the cost of commuting between the prey resources and the nest. Because of the spatial and temporal variability of marine ecosystems, individuals must adapt their behaviour to increase foraging success within these constraints. The at-sea movements, foraging behaviour and effort of the Australasian gannet (Morus serrator) was determined over three sequential breeding seasons of apparent differing prey abundance to investigate how the species adapts to inter-annual fluctuations in food availability. GPS and tri-axial accelerometer data loggers were used to compare the degree of annual variation within two stages of breeding (incubation and chick rearing) at a small gannet colony situated between two larger, nearby colonies. Interestingly, neither males nor females increased the total distance travelled or duration of foraging trip in any breeding stage (P>0.05 in all cases) despite apparent low prey availability. However, consistently within each breeding stage, mean vectorial dynamic body acceleration (an index of energy expenditure) was greater in years of poorer breeding success (increased by a factor of three to eight), suggesting birds were working harder within their range. Additionally, both males and females increased the proportion of a foraging trip spent foraging in a poorer year across both breeding stages. Individuals from this colony may be limited in their ability to extend their range in years of low prey availability due to competition from conspecifics in nearby colonies and, consequently, increase foraging effort within this restricted foraging area.

Perks and the informativeness of stock prices in the Chinese market

While the literature shows that perks can affect firm values positively or negatively, we argue that firms with higher perks are more likely to be associated with a lower quality of financial reporting, which, in turn, can affect the informativeness of stock prices. Based on hand-collected data on perks from Chinese listed firms, we find that firms with lower perks are associated with higher informativeness of stock prices (or lower R-square). Moreover, the positive association between perks and R-square is shown to be weaker for firms with higher financial reporting quality through audit and earnings quality measures.

Does board gender diversity improve the informativeness of stock prices?

We show that stock prices of firms with gender-diverse boards reflect more firm-specific information after controlling for corporate governance, earnings quality, institutional ownership and acquisition activity. Further, we show that the relationship is stronger for firms with weak corporate governance suggesting that gender-diverse boards could act as a substitute mechanism for corporate governance that would be otherwise weak. The results are robust to alternative specifications of informativeness and gender diversity and to sensitivity tests controlling for time-invariant firm characteristics and alternative measures of stock price informativeness. We also find that gender diversity improves stock price informativeness through the mechanism of increased public disclosure in large firms and by encouraging private information collection in small firms. © 2011 Elsevier B.V.

Counting the cost: the impact of cinema ticket prices in Australia

The authors discuss the change in cinema ticket price and its effect on audience perception on cinema attendance in Australia. Topics discussed include the comparison of ticket prices in Australia to countries such as the U.S., Japan, and New Zealand, the reason of high ticket prices in Australia such as high wages in theatre operation and piracy, and the drop of cinema admission as result of high ticket prices. They mention the social equity issues raised by the high cost of cinema tickets.

Smartphone apps to improve fitness and increase physical activity among young people: protocol of the Apps for IMproving FITness (AIMFIT) randomized controlled trial

BACKGROUND: Physical activity is a modifiable behavior related to many preventable non-communicable diseases. There is an age-related decline in physical activity levels in young people, which tracks into adulthood. Common interactive technologies such as smartphones, particularly employing immersive features, may enhance the appeal and delivery of interventions to increase levels of physical activity in young people. The primary aim of the Apps for IMproving FITness (AIMFIT) trial is to evaluate the effectiveness of two popular "off-the-shelf" smartphone apps for improving cardiorespiratory fitness in young people.

METHODS/DESIGN: A three-arm, parallel, randomized controlled trial will be conducted in Auckland, New Zealand. Fifty-one eligible young people aged 14-17 years will be randomized to one of three conditions: 1) use of an immersive smartphone app, 2) use of a non-immersive app, or 3) usual behavior (control). Both smartphone apps consist of an eight-week training program designed to improve fitness and ability to run 5 km, however, the immersive app features a game-themed design and adds a narrative. Data are collected at baseline and 8 weeks. The primary outcome is cardiorespiratory fitness, assessed as time to complete the one mile run/walk test at 8 weeks. Secondary outcomes are physical activity levels, self-efficacy, enjoyment, psychological need satisfaction, and acceptability and usability of the apps. Analysis using intention to treat principles will be performed using regression models.

DISCUSSION: Despite the proliferation of commercially available smartphone applications, there is a dearth of empirical evidence to support their effectiveness on the targeted health behavior. This pragmatic study will determine the effectiveness of two popular "off-the-shelf" apps as a stand-alone instrument for improving fitness and physical activity among young people. Adherence to app use will not be closely controlled; however, random allocation of participants, a heterogeneous group, and data analysis using intention to treat principles provide internal and external validity to the study. The primary outcome will be objectively assessed with a valid and reliable field-based test, as well as the secondary outcome of physical activity, via accelerometry. If effective, such applications could be used alongside existing interventions to promote fitness and physical activity in this population. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry: ACTRN12613001030763. Registered 16 September 2013.

Asymmetric oil shocks and external balances of major oil exporting and importing countries

This study investigates the effects of oil price shocks on three measures of oil exporters' and oil importers' external balances: total trade balance, oil trade balance and non-oil trade balance. We employ three second-generation heterogeneous linear panel models and one recently developed non-linear panel estimation technique that allows for cross-sectional dependence. With respect to 28 major oil exporting countries, an increase in oil prices leads to an improved real oil trade balance, although it is detrimental to non-oil and total trade balances. This finding might be due to the expenditure effect arising from increases in proceeds from oil exports. A decrease in oil prices is found to be beneficial for both total and oil trade balances in these oil exporting countries. Forty major oil importers seem to be increasingly shielded from positive oil shocks over the 1970s and 1980s; however, they must worry about oil price declines. A decline in oil prices has a negative impact on both total and real oil trade balances resulting from increased oil imports in emerging economies. Hence, a decline in oil prices is beneficial to oil exporters due to the quantity effect outweighing the price effect, while for oil importers a stable oil price is more desirable than a price decline. These results are important to take into account if we are to gain a full understanding on the magnitude of the trade and macroeconomic effects of oil price changes and what the policy responses should be.

Stock market liquidity and firm value : an empirical examination of the Australian market

We document a positive relation between stock liquidity and firm value. We examine the mechanism through which stock market liquidity enhances firm value by dividing firm value, as measured by Tobin’s Q, into three components, namely, operating income to price, leverage, and operating income to assets. Using the switch to broker anonymity as an exogenous shock to market liquidity, we show that the increase in liquidity around the shock leads to an increase in firm value. Our results suggest that higher firm value for more liquid stocks seems to stem from enhanced stock prices rather than from better operating performance.