Simultaneous control of spectroscopic and electrochemical properties in functionalised electrochemiluminescent tris(2,2'-bipyridine)ruthenium(II) complexes

Using a combination of electrochemical, spectroscopic and computational techniques, we have explored the fundamental properties of a series of ruthenium diimine complexes designed for coupling with other molecules or surfaces for electrochemiluminescence (ECL) sensing applications. With appropriate choice of ligand functionality, it is possible to manipulate emission wavelengths while keeping the redox ability of the complex relatively constant. DFT calculations show that in the case of electron withdrawing substituents such as ester or amide, the excited state is located on the substituted bipyridine ligand whereas in the case of alkyl functionality it is localised on a bipyridine. The factors that dictate annihilation ECL efficiency are interrelated. For example, the same factors that determine ΔG for the annihilation reaction (i.e. the relative energies of the HOMO and LUMO) have a corresponding effect on the energy of the excited state product. As a result, most of the complexes populate the excited state with an efficiency (Φex) of close to 80% despite the relatively wide range of emission maxima. The quantum yield of emission (Φp) and the possibility of competing side reactions are found to be the main determinants of ECL intensity.

A robust solution to the stereo-vision-based simultaneous localization and mapping problem with steady and moving landmarks

The problem of visual simultaneous localization and mapping (SLAM) is examined in this paper using recently developed ideas and algorithms from modern robust control and estimation theory. A nonlinear model for a stereo-vision-based sensor is derived that leads to nonlinear measurements of the landmark coordinates along with optical flow-based measurements of the relative robot-landmark velocity. Using a novel analytical measurement transformation, the nonlinear SLAM problem is converted into the linear domain and solved using a robust linear filter. Actually, the linear filter is guaranteed stable and the SLAM state estimation error is bounded within an ellipsoidal set. A mathematically rigorous stability proof is given that holds true even when the landmarks move in accordance with an unknown control input. No similar results are available for the commonly employed extended Kalman filter, which is known to exhibit divergence and inconsistency characteristics in practice. A number of illustrative examples are given using both simulated and real vision data that further validate the proposed method.

Volatility decomposition of Australian housing prices

This study examines the volatility pattern of Australian housing prices. The approach for this research was to decompose the conditional volatility of housing prices into a “permanent” component and a “transitory” component via a Component-Generalized Autoregressive Conditional Heteroskedasticity (C-GARCH) model. The results demonstrate that the shock impact on the short-run component (transitory) is much larger than the long-run component (permanent), whereas the persistence of transitory shocks is much less than permanent shocks. Moreover, both permanent and transitory volatility components have different determinants. The results provide important new insights into the volatility pattern of housing prices which has direct implications for investment in housing by owner-occupiers and investors.

Low-frequency volatility of yen interest rate swap market in relation to macroeconomic risk

Using ‘low-frequency’ volatility extracted from aggregate volatility shocks in interest rate swap (hereafter, IRS) market, this paper investigates whether Japanese yen IRS volatility can be explained by macroeconomic risks. The analysis suggests that this low-frequency yen IRS volatility has strong and positive association with most of the macroeconomic risk proxies (e.g., volatility of consumer price index, industrial production volatility, foreign exchange volatility, slope of the term structure and money supply) with the exception of the unemployment rate, which is negatively related to IRS volatility. This finding is fairly consistent with the argument that the greater the macroeconomic risk the greater is the use of derivative instruments to hedge or speculate. The relationship between the macroeconomic risks and IRS volatility varies slightly across the different swap maturities but is robust to alternative volatility specifications. This linkage between swap market and macroeconomy has practical implications since market makers and hedgers use the swap rate as benchmark for pricing long-term interest rates, corporate bonds and various other securities.

Volatility spillover between New Zealand stock market returns and exchange rate changes before and after the 1997 Asian financial crisis

Researchers in the last decade have been investigating the interdependence of stock returns and exchange rate changes within the same economy. Kanas (2000) and Yang and Doong (2004) find that for the G-7 countries, in general, the volatility of the stock market spills over to the exchange rate market but that volatility spillovers from the exchange rate market to the stock market are insignificant. Chen, Naylor, and Lu (2004) find that NZ individual firm returns are significantly exposed to exchange rate changes. This study complements their work by investigating the volatility spillover between the stock market and the foreign exchange market within the NZ economy.

Volatility linkages and spillovers in stock and bond markets : some international evidence

This study investigates the transmission of market-wide volatility between the equity markets and bond markets of Japan, Germany, the U. K., and the U. S. To measure the volatility transmission, the BEKK- a decomposition approach to the multivariate GARCH (1,1) model, is used to examine the cross-market contemporaneous effect of information arrival. Our results suggest that within the domestic cross markets, the volatility transmission is undirectional from the stock market to the bond market. Evidence from international cross-market analysis is mixed, with strong evidence on volatility spillover among these international stock markets, but weak evidence between international stock and bond markets. In addition, there are significant bi-directional volatility transmissions between stock markets in Germany and the U. K., and between Germany and the U. S. The volatility transmissions among these markets suggest that the international diversification of bonds is not prevalent.

Volatility transmissions between stock and bond markets : evidence from Japan and the U.S.

This study attempts to investigate the transmission of market-wide volatility between the equity markets and bond markets of Japan and the U.S. To measure the volatility transmission, the BEKK (Baba, Engle, Kraft and Kroner, 1990) method, a decomposition approach of the multivariate GARCH (1,1) model, is used to examine the cross-market contemporaneous effect of information arrival. The time series analysis provides evidence to the long-run phenomena of causality in conditional variances of paired assets within the local and international markets. Within various pairings, some evidence of bi-directional volatility transmissions such as informational linkages have been observed. Our empirical results suggest that within the domestic cross markets, the volatility transmission is unidirectional from the stock market to the bond market. Evidence from international cross-market analysis is mixed, with strong evidence on volatility spillover among these international stock markets, but weak evidence between international stock and bond markets. In addition, there are significant directional volatility transmissions between DJI index and FTSE100 index, and between DJI index and DAX200 index. The volatility transmission between these two markets indicates that the international diversification of bonds is not prevalent.

Volatility transmission between stock and bond markets : evidence from US and Australia

This paper investigates the cross-market informational dependence between these assets under disparate interest rate conditions of the U.S and Australia. With conditional variance as a proxy for volatility, we use the BEKK – a matricular decomposition of the bivariate GARCH (1,1) model to examine the cross-market contemporaneous effect of information arrival. Applying the model to the stock and bond indices of both countries, we find evidence of volatility spillover, thereby supporting the notion of informational dependence between each market

Modeling volatility and changes in the swap spread

We investigate the determinants of changes in U.S. interest rate swap spreads using a model that explicitly allows for volatility interactions between swaps of different terms to maturity. Changes in the swap spread are found to be positively related to interest rate volatility, to changes in the default risk premium in the corporate bond market, and to changes in the liquidity premium for government securities. Swap spread changes are negatively related to changes in the level of interest rates and changes in the slope of the term structure. We also find that there is a strong and significant volatility interaction among spreads for swaps of different maturities and that the process for the conditional variance of the spread is highly persistent across all maturities.

Exploring Australian housing supply volatility

This study examines the volatility series of housing supply in Australia. A Generalised Autoregressive Conditional Heteroskedasticity-in-Mean (GARCH-M) model is employed to analyse the volatility series of Australian housing supply over the study period of 1974-2010. The results show the volatility of housing starts is negatively linked to housing starts, suggesting that higher uncertainty does lower housing starts. The results also reveal that the uncertainty of housing starts is also captured by the volatilities of interest rates and construction costs. Therefore policy makers should monitor and attempt to minimise the volatility of housing supply. These steps will enhance housing construction activities and increase the availability of housing supply to potential home buyers.