Complex network analysis of volatility spillovers between global financial indicators and G20 stock markets.

This paper analyses the dynamic transmission mechanism of volatility spillovers between key global financial indicators and G20 stock markets. To examine volatility spillover relations, we combine a bivariate GARCH-BEKK model with complex network theory. Specifically, we construct a volatility network of international financial markets utilising the spatial connectedness of spillovers (consisting of nodes and edges). The findings show that spillover relations between global variables and G20 markets vary significantly across five identified sub-periods. Notably, networks are much denser in crisis periods compared to non-crisis periods. In comparing two crisis periods, Global Financial Crisis (2008) and COVID-19 Crisis (2020) periods, the network statistics suggest that volatility spillovers in the latter period are more transitive and intense than the former. This suggests that financial volatility spreads more rapidly and directly through key financial indicators to the G20 stock markets. For example, oil and bonds are the largest volatility senders, while the markets of Saudi Arabia, Russia, South Africa, and Brazil are the main volatility receivers. In the former crisis, the source of financial volatility concentrates primarily in the USA, Australia, Canada, and Saudi Arabia, which are the largest volatility senders and receivers. China emerges as generally the least sensitive market to external volatility.

Factors Affecting Dental Students' Comfort with Online Synchronous Learning.

Background: The COVID-19 pandemic caused many universities to expand their use of videoconferencing technology to continue academic coursework. This study examines dental students' experience, comfort levels, and preferences with videoconferencing. Methods: Of 100 s-year US dental students enrolled in a local anesthesia course, 54 completed a survey following an online synchronous lecture given in August 2020. Survey questions asked about prior experience with videoconferencing, comfort levels with online and traditional classes, and reasons for not turning on their video (showing their face). Results: Overall, 48.2% had little or no experience with videoconferencing prior to March 2020. Students were more comfortable with in-classroom parameters (listening, asking questions, answering questions, and interacting in small groups (breakouts)) than with online synchronous learning, although differences were not significant (p's > 0.10). Regression analyses showed there were significant positive associations between videoconferencing experience and comfort with both answering questions and interacting in breakouts (B = 0.55, p = 0.04 and B = 0.54, p = 0.03, respectively). Students reported being more comfortable during in-classroom breakouts than in breakouts using videoconferencing (p = 0.003). Main reasons for students not turning on their cameras were that they did not want to dress up (48.1%), other students were not using their video features (46.3%), and they felt they did not look good (35.5%). Conclusions: Dental students were somewhat more comfortable with traditional in-person vs. online classroom parameters. Prior experience with videoconferencing was associated with increased comfort with synchronous learning, suggesting that after the pandemic, it may be beneficial to structure dental school curricula as a hybrid learning experience with both in-person and online synchronous courses.

The Time-Varying Relation between Stock Returns and Monetary Variables

The nature of the relation between stock returns and the three monetary variables of interest rates (bond yields), inflation and money supply growth, while oft studied, is one that remains unclear. We argue that the nature of the relation changes over time, and this variation is largely driven by shocks, with a change in risk associated with each variable shifting the pattern of behaviour. We show a change in the correlation between each of the three variables with stock returns. Notably, a predominantly negative correlation with bond yields and inflation becomes positive, while the opposite is true for money supply growth. The shift begins with the bursting of the dotcom bubble but is exacerbated by the financial crisis. Results of predictive regressions for stock returns also indicate a switch in behaviour. Predominantly negative predictive power switches temporarily to positive around economic shocks. This suggests that higher yields, inflation and money growth typically depress returns but support the market during periods of stress. However, after the financial crisis, higher inflation and money growth exhibit persistent positive predictive power and suggest a change in the risk perception of higher values.