• Journal of Korean Academy of Nursing
• /
• v.37 no.2
• /
• pp.227-241
• /
• 2007

Background. Although research has established the existence of an association between smoking and depression among adolescents, researchers have not reached consensus on the nature of the association. Objectives. The purpose of this paper is to review the literature, to examine the nature of the relationship between smoking and depression in adolescence, and to suggest future research directions. Methods. A literature search was conducted from the following six databases: (a) Ovid MEDLINE, (b) CINAHL, (c) PubMed Unrestricted, (d) PsycINFO, (e) ERIC, and (f) Sociological Abstracts. The combinations of the words, "depression," "smoking," "tobacco," "adolescent," and "teen" were used for keyword searches to find relevant articles. Results. In 47 of 57 studies, significant associations between smoking and depression were found. However, these significant relationships may either be spurious or unrelated to depression because a substantial number of studies did not adjust for confounders or did not use validated instruments to measure depression. Additionally, if the relationship is causal, its direction remains controversial. Five relationships have been suggested: (a) Depression causes smoking, (b) smoking causes depression, (c) there is a bidirectional relationship between smoking and depression, (d) smoking and depression occur due to confounders, and (e) subgroups with different relationships between the two conditions exist. Conclusions. It is necessary to further explore the relationship between smoking and depression. Future research should consider the need for: (a) longitudinal research designs, (b) more accurate measurement of depression, and (c) the control of confounders between smoking and depression.

• The Journal of Asian Finance, Economics and Business
• /
• v.7 no.8
• /
• pp.41-49
• /
• 2020

This study investigates the short-run and long-run causal behavior of the Philippine stock market index volatility under vector error correction environment. The variables were tested first for stationarity and then long-run equilibrium relationship. Moreover, an impulse response function was estimated to examine the extent of innovations in the independent variables in explaining the Philippine stock market index volatility. The results reveal that the volatility of the Philippine stock market index exhibit long-run equilibrium relationship with Peso-Dollar exchange rate, London Interbank Offered Rate, and crude oil prices. The short-run dynamics-based VECM estimates indicate that in the short-run, increases (i.e., depreciation) in Peso-Dollar exchange rate cause PSEI volatility to increase. As for the London Interbank Offered Rate, it causes increases in PSEI volatility in the short-run. The adjustment coefficients used with the long-run dynamics validates the presence of unidirectional causal long-run relationship from Peso-Dollar exchange rate, London Interbank Offered Rate, and crude oil prices to PSEI volatility, and bidirectional causal long-run relationship between PSEI volatility and London Interbank Offered Rate. The impulse response functions developed within the VECM framework demonstrate the positive and negative reactions of PSEI volatility to unanticipated Peso-Dollar exchange rate, London Interbank Offered Rate, and crude oil price shocks.

• The Journal of Asian Finance, Economics and Business
• /
• v.6 no.4
• /
• pp.115-128
• /
• 2019

The study aims to investigate the pattern of relationships such as symmetric or asymmetric, between exchange rate and foreign direct investment in Bangladesh by applying Autoregressive Distributed Lagged (ARDL) and nonlinear ARDL. In this study, we employed quarterly data for the period of 1974Q1 to 2016Q4. Data were collected and aggregated from various sources namely, Bangladesh Economic Review published by Ministry of Finance and statistical yearbook published by Bangladesh Bureau of Statistics and an annual report published by Bangladesh Bank. The relationship between exchange rate and FDI inflows attract immense interest in the recent periods, especially for developing countries' perspective. The results of the study ascertain the long run relationship between FDI, exchange rate, monetary policy, and fiscal policy. Considering the asymmetric assumption, the findings from NARDL confirm the existence of a long-run asymmetric relationship in the empirical equation. In the long run, it is observed that positive change that is the appreciation of exchange rate against USD decrease FDI inflows and negative shocks results in grater inflows of FDI, however, the positive shocks produce higher intensity that negative shocks in Exchange rate. For directional causality, the coefficients of error correction term confirm long-run causality, in particular, bidirectional causality unveiled between FDI and exchange rate.

• The Journal of Asian Finance, Economics and Business
• /
• v.7 no.9
• /
• pp.1-10
• /
• 2020

The purpose of this study is to investigate the relationship between diversification and the performance of commercial banks, while taking into account the ownership status of these banks in Sri Lanka. Two-way relationship between diversification and performance was scrutinised by employing the 2SLS regression technique. The data consists of 17 registered commercial bank in Sri Lanka between 2001-2016. The results show a strong significant bidirectional relationship exists between diversification and bank performance. The performance of Sri Lankan banks has been significantly improved by their diversification attempts. In other words, the banks whose incomes are more diversified from various sources, they are more profitable and successful in long-term. On the other hands, the results also reveal that bank performance positively and significantly affects diversification. This finding suggests that the banks with great profitability are more capable in diversify their operations. Furthermore, private sector banks, both listed and unlisted, are significantly more diversified than their government-owned counterparts, but their performance is not necessarily superior to government-owned banks. This may be the result of the economic environment and the perception of the public, which have allowed the government-owned banks to entertain significant market power over the private sector banks in the country.

• Environmental Engineering Research
• /
• v.22 no.2
• /
• pp.193-202
• /
• 2017

The study estimated the relationship between carbon dioxide, crop and livestock production index in Ghana: Estimating the long-run elasticities and variance decomposition by employing a time series data spanning from 1960-2013 using both fit regression and ARDL models. There was evidence of a long-run equilibrium relationship between carbon dioxide emissions, crop production index and livestock production index. Evidence from the study shows that a 1% increase in crop production index will increase carbon dioxide emissions by 0.52%, while a 1% increase in livestock production index will increase carbon dioxide emissions by 0.81% in the long-run. There was evidence of a bidirectional causality between a crop production index and carbon dioxide emissions and a unidirectional causality exists from livestock production index to carbon dioxide emissions. Evidence from the variance decomposition shows that 37% of future fluctuations in carbon dioxide emissions are due to shocks in the crop production index while 18% of future fluctuations in carbon dioxide emissions are due to shocks in the livestock production index. Efforts towards reducing pre-production, production, transportation, processing and post-harvest losses are essential to reducing food wastage which affects Ghana's carbon footprint.

• The Journal of Asian Finance, Economics and Business
• /
• v.8 no.3
• /
• pp.191-199
• /
• 2021

The study examines the causal relationship between financial development and economic growth through trade openness for the leading ASEAN countries (Indonesia, the Philippines, Malaysia, Singapore, Thailand, and Vietnam). The study employs a panel data for the period of 25 years spanning from 1995 to 2015 for the six countries, yielding a balanced panel of 150 observations. Fixed effect model (FEM) and random effect model (REM) are used for the panel data, following the Hausman test performed for model selection. The trivariate Granger causality test is also used to check for possible relationship between the variables. The results show that REM is chosen based on the Hausman test result, suggesting that the trade openness has a positive association with growth whereas the financial development is positively, but insignificantly associated with growth. The reason for this is that the financial development and economic growth may be related to each other. The results are, then, further explored and confirmed by the causality test. That is, the financial development and the economic growth, through the trade openness, are found to have bidirectional positive relationships. This implies that there would be shortcomings when ignoring the presence of trade openness, which positively impacts the relationship between finance and growth.

• Structural Engineering and Mechanics
• /
• v.85 no.4
• /
• pp.469-484
• /
• 2023

A deep recursive bidirectional Cuda Deep Neural Network Long Short Term Memory (Bi-CuDNNLSTM) layer is recruited in this paper to predict the entire force time histories, and the corresponding hysteresis and backbone curves of reinforced concrete (RC) bridge piers using experimental fast and slow cyclic tests. The proposed stacked Bi-CuDNNLSTM layers involve multiple uncertain input variables, including horizontal actuator displacements, vertical actuators axial loads, the effective height of the bridge pier, the moment of inertia, and mass. The functional application programming interface in the Keras Python library is utilized to develop a deep learning model considering all the above various input attributes. To have a robust and reliable prediction, the dataset for both the fast and slow cyclic tests is split into three mutually exclusive subsets of training, validation, and testing (unseen). The whole datasets include 17 RC bridge piers tested experimentally ten for fast and seven for slow cyclic tests. The results bring to light that the mean absolute error, as a loss function, is monotonically decreased to zero for both the training and validation datasets after 5000 epochs, and a high level of correlation is observed between the predicted and the experimentally measured values of the force time histories for all the datasets, more than 90%. It can be concluded that the maximum mean of the normalized error, obtained through Box-Whisker plot and Gaussian distribution of normalized error, associated with unseen data is about 10% and 3% for the fast and slow cyclic tests, respectively. In recapitulation, it brings to an end that the stacked Bi-CuDNNLSTM layer implemented in this study has a myriad of benefits in reducing the time and experimental costs for conducting new fast and slow cyclic tests in the future and results in a fast and accurate insight into hysteretic behavior of bridge piers.

• Environmental Engineering Research
• /
• v.22 no.1
• /
• pp.40-54
• /
• 2017

According to FAO, "agricultural sectors are particularly exposed to the effects of climate change and increases climate variability". As a result, the study makes an attempt to answer the question: Is there a causal effect between agricultural production and carbon dioxide emissions in Ghana? By employing a time series data spanning from 1960 to 2015 using the Autoregressive Distributed Lag method. There was evidence of a long-run equilibrium relationship running from copra production, corn production, green coffee production, milled rice production, millet production, palm kernel production and sorghum production to carbon dioxide emissions. The short-run equilibrium relationship shows that, a 1% increase in copra and green coffee production will increase carbon dioxide emissions by 0.22% and 0.03%, a 1% increase in millet and sorghum production will decrease carbon dioxide emissions by 0.13% and 0.11% in the short-run while a 31% of future fluctuations in carbon dioxide emissions are due to shocks in corn production. There was bidirectional causality between milled rice production and carbon dioxide emissions, millet production and carbon dioxide emissions and, sorghum production and carbon dioxide emissions; and a unidirectional causality running from corn production to carbon dioxide emissions and carbon dioxide emissions to palm kernel production.

• Sleep Medicine and Psychophysiology
• /
• v.22 no.2
• /
• pp.53-56
• /
• 2015

Good sleepers tend to more resilient than poor sleepers. As sleep and resilience may have a bidirectional relationship, it is important to explore the relationship between healthy sleep and resilience. Objectively and subjectively measured sleep quality showed positive association with resiliency. In one study, more resilient adolescents had higher sleep efficiency, less light sleep, more slow-wave sleep, and a smaller number of awakenings after sleep onset. Circadian typology, jetlag and circadian misalignment may be associated with the capacity to deal with adversity. Eveningness, exposure to chronic jetlag and circadian misalignment might be risk factors for development of psychological problems and mental disorders. Additional studies are needed to evaluate whether promoting healthy sleep behaviors results in increased resilience.

• The Journal of Asian Finance, Economics and Business
• /
• v.7 no.11
• /
• pp.607-617
• /
• 2020

This study investigates the causal relationship between public and private external debt and economic growth in developing countries. Our model includes 18 selected Asian developing and transition economies from 1995 thru 2019. We employ the dynamic heterogeneous panel data methods, pooled mean group (PMG), robust cross-sectional augmented autoregressive distributed lag (CS-ARDL), and pairwise panel causality test. The results of PMG and CS-ARDL show the existence of causality between external debt and economic growth both in the short-run and long-run. The pairwise Granger causality test found the bidirectional causal relationship runs from total external debt, public external debt, and private external debt to economic growth and economic growth to external debt. The results showed first the existence of causality in the short-run and long-run between external debt and economic growth and the second, bi-directional causality that runs from external debt to economic growth and economic growth to external debt. Both the dynamic models and robust estimator found the same inferences about the impact of main variables on economic growth in Asian developing and transition economies. The findings of this study suggest to assure debt management, investment in productive sectors, increase domestic savings, decrease external dependency, and focus on international trade.