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It is currently difficult to measure temperature and pressure in harsh environments. Such measurements are limited by either the ability of the sensing element or the associated electrical wiring to withstand the operating environment. This is unfortunate as temperature and pressure are important measurands in various engineering structures as they provide critical information on the operating condition of the structure. Hence, there is a need to address this shortcoming. Such a sensor in place would enhance the operating efficiency thereby reducing the pollution burden and its impact on the environment. The purpose of this paper is to present theoretical and preliminary experimental results for a co‐integrated pressure and temperature sensor for harsh environments.

This work describes a co‐integrated pressure‐temperature wireless sensing scheme. The approach presented herein provides the possibility of measuring dynamic pressure and temperature within an enclosed volume using acoustic signals. Resonance tube physics is exploited for the temperature sensing. A microphone is used to obtain the acoustic signal whose frequency is a function of the temperature and the tube geometry.

The dynamic pressure is measured from the calibrated amplitude of the pressure wave signal measured by the microphone. The temperature can be measured through the shift of the standing wave frequency with a resolution of <1°C. The resonance tube can be fabricated using any material that resists harsh environments. The geometry of the tube can be tailored for any specific frequency range, as the application warrants. Also, this provides a means for accurate temperature compensation of pressure sensor data from high temperature environments. A Matlab/Simulink model is developed and presented for the acquisition of acoustic signals through the wall of an enclosed volume. For these applications the standing wave signal transmitted through the enclosure wall becomes a function of the wall material and wall thickness. Preliminary experimental results are presented in which a DC fan is used for generating the dynamic pressure in a varying temperature environment.

The major issue is the separation of the noise from the signal. As various applications yield specific signal noise, the problem needs detailed data to be addressed.

Temperature and dynamic pressure could be recorded/monitored in very harsh environment conditions such as chemical reactors.

This work demonstrates the possibility of employing a co‐integrated acoustic sensing scheme in which both pressure and temperature are measured simultaneously with a sole sensor. The major advantage with acoustic sensing is the wireless transmission of data. This allows for non‐invasive measurement from within enclosed systems. Direct real‐time temperature compensation is possible that does not require any compensation circuitry. Hence, pressure and temperature data may be obtained from caustic operating environments whose access is otherwise not feasible.

Several recent studies have indicated the existence of a predictable component in stock prices. This study examines the sources of this serial correlation using error‐correction models. The results show that autocorrelated economic variables can generate serial correlation in stock returns. After these effects are accounted for, however, significant serial correlation in stock prices remains. The activities of noise traders and inefficiencies in the pricing of securities, within the context of limitations to the arbitrage process, are suggested as additional sources of serial correlation in stock prices.

In financial analysis, forecasting often involves regressing one time series variable on another. However, to ensure that the models are correctly specified, one needs to first test for stationarity, co‐integration and causality. In testing for causality, the variables should be stationary. If non‐stationary, one can estimate the model in difference form, unless the variables are co‐integrated. This article determines whether cash flow and earnings variables are stationary, and which variable causes the other, using econometric analysis. In most cases, cash flow variables are found to cause earnings variables. This is so when the models are estimated in levels. However, when estimated in first differences, the causal relationship tends to be reversed such that earnings cause cash flows. Further study is recommended, whereby panel data could be used to improve the power of the tests.

Summarizes three explanations put forward in previous research for the deviation of closed‐end fund (CEF) share prices from their net asset values and tests the theories based on market sentiment (noise trading) and market segmentation (market frictions). Analyses 1991‐1997 data on 18 UK CEFs (13 investing in the UK and 5 in the USA) to explore the pattern of cointegration and error corrected Granger causality between the fund discounts and indices which proxy for UK and US investor sentiment. Discusses the results, which support both theories for UK CEFs and show some evidence of cointegration and information transmission. Briefly considers consistency with other research and the implications of the findings.

The purpose of this paper is to present a method of forecasting the development of the market shares of competitors in a pursuit race.

The statistical concept of co‐integration is applied to a state space model in order to operationalize the pursuit race in competition. Two time series served as data input for the designed model. They document the development of the monthly market shares of German savings banks and German cooperative banks with respect to the end‐of‐month volume of non‐bank deposits.

The analysis of the competition between the two bank groups proves that the development of their market shares is co‐integrated in the shape of a long lasting pursuit race. Therefore, the forecasts of the changes in market shares are very accurate and reliable.

With the help of such a statistical analysis, a competitor is able to monitor the development of competition effectively to forecast the changes that are to be expected. Thus, the method described here helps the firm to react in time to the movements of its competitors.

This paper is an important contribution to gain insight in the quantitative dynamics of competition according to co‐integration by the parameters of state space model.

The purpose of this paper is to assess the benefits to investors of international diversification among only Islamic funds. Compared to conventional investors who are not restricted in their choice of funds, Islamic investors are restricted to investing in shari’a-compliant funds, thus giving up some diversification benefits. The possibility of international diversification among only Islamic funds may thus help Islamic investors to invest in accordance to their religious beliefs and still benefit from diversification.

The paper assesses the benefits of diversification by analyzing the extent of co-integration among four regional Islamic funds and by estimating the short-term and long-term structural dynamics of and among these funds. The paper uses an Autoregressive-Distributed Lag (ARDL) approach to testing the long-run relationships among these funds and use variance decomposition and impulse response functions to examine the structural dynamics of the relationship between these funds. These methods can also be used for predictive purposes and represent, in authors opinion, a useful approach that complements the traditional methodology of static covariance matrix to find the efficient frontier at a given moment in time.

The results indicate that international diversification can help reduce risk if Asia Pacific Islamic funds and MENA region Islamic funds are invested contemporaneously and/or Asia Pacific Islamic funds and North America Islamic funds, and/or Europe funds and MENA funds. The paper also finds that investors would benefit from investing in North American funds and MENA funds both in the long run and in the short run. Conversely, the paper finds that Europe funds and North American funds are co-integrated in the long-run precluding the opportunity for substantial diversification benefits from these particular portfolio mixes.

The long-run analysis helps passive fund managers and investors in composing their portfolio by providing evidence that some portfolio mixes of different regional Islamic funds lead to better risk return performance than one regional Islamic fund portfolios. The short-run analysis however helps the active fund managers and investors as it suggests that diversifying in the short run and reviewing their portfolio on a regular basis would be beneficial as well.

This analysis justifies the promotion of Islamic finance as the negative correlation between several Islamic funds across the regions studied suggests better opportunities of investments via international diversification making Islamic funds more desirable.

This paper seeks to examine the validity of Wagner's Law using annual data (1957‐2006) for the US state‐local government (SLG) real expenditure and eight of its sub‐categories.

The co‐integration tests of Johansen and the bounds testing approach to co‐integration proposed by Pesaran et al. were carried out to determine whether a long‐term equilibrium relationship existed between real per capita GDP (pcgdp) and the expenditure variables scaled by real GDP. The income elasticity coefficients of the expenditure variables were then estimated. The direction of causality was tested in the context of error‐correction models (ECM) and the Toda‐Yamamoto approach, which allows for estimating level relationships without pre‐testing for unit roots.

Most SLG expenditure variables were found to be non‐stationary and income‐elastic. However, with the exception of total expenditure (te), insurance trust benefits (ins) and social services and income maintenance (ssim), no other non‐stationary expenditure variable was co‐integrated with pcgdp and error‐corrected over time. The ECM results suggested that te, ins and ssim were driven by pcgdp, consistent with a Wagnerian causal ordering. The Toda‐Yamamoto approach, however, indicated that in these and a few other cases the causal effect was bidirectional.

This paper provides a fairly comprehensive test of Wagner's Law at the US sub‐national government level with an emphasis on the concepts of co‐integration and (long‐run) causality in the income‐expenditure nexus. Its findings underscore the importance of using disaggregated expenditure measures to test Wagner's Law, as they suggest that some, but not all, rapidly growing and non‐stationary expenditure sub‐categories were decoupled from pcgdp in the long run.

The purpose of this paper is to make an empirical analysis concerning time-inconsistency problem (TIP) based on a sample of 12 countries for the period from 1993 to 2011.

The existence of TIP only makes sense if there is a trade-off between inflation and unemployment and when there is a causal relationship indicating that with more inflation, unemployment is reduced (as suggested by the Phillips curve). Hence, TIP is observed by testing the existence of cointegration between inflation rate and unemployment rate series and analyzing the sign of the estimated coefficient of the cointegration vector.

The findings indicate that the large majority of countries in the sample have policies that are consistent with long-term goals. Furthermore, it is possible to conjecture that the traditional argument that developing countries have weak institutions and thus present a fertile ground for TIP or that the adoption of inflation targeting (IT) can avoid TIP is not necessarily true.

This study sheds light on four important issues. First, has the change in the mindset of the monetary policy management from the 1990s eliminated TIP? Second, is TIP a sickness only for developing countries? Third, is IT associated with TIP? Fourth, has the TIP increased around the world due to the subprime crisis? In short, this paper is an advance on the empirical literature on TIP and it is a very important overview for observing the present day conduct of the monetary policy through the international experience.

The purpose of this research is to examine the nature of housing market affordability. Although the problem of housing affordability has been widely discussed, the theoretical underpinnings of the concept have received less attention. It has become increasingly evident that more holistic insights and integrated approaches are needed to provide a platform to define affordability to influence research and policy discourse.

Given the increasing importance of affordability within housing policy reform, this paper seeks to “unearth” the most important prognosticators of affordability. The paper uses principal component analysis to determine how affordability, as a key policy tool, should be analysed. In addition, co integration techniques, Granger causality and impulse response analysis are applied to test the movement and shocks of the key affordability indicators and the two common affordability metrics.

The principal conclusions stemming from this paper demonstrate that affordability is a multifaceted policy concept influenced by financial access (purchase) costs and the repayment costs of housing services which are correlated and interchangeable but significantly were found not to be co integrated.

Understanding the nature of housing market affordability remains problem for policy-makers. This paper adds to the debate and empirical understanding of the cyclic nature of affordability and how it is defined. It shows that there are intricate causal short-term relationships between the key affordability indicators. This is problematic for contemporary housing policy and the key directions in which policy must turn.

To analyze the impact of agricultural sector on the economy of North Cyprus, which suffers from political problems and drought over the years.

Annual data covering 1975‐2002 period has been used to find the direction of causality in Granger sense between agricultural growth and economic growth after employing unit root tests to see if the variables under consideration are stationary.

Results of the present study first suggest that agricultural output growth and economic growth as measured by real gross domestic product growth are stationary at their levels, thus, they are naturally co‐integrated. They are in long run equilibrium relationship. And secondly, there is feedback relationship between these variables that indicates bidirectional causation among them in the long run period.

A more expanded data can be used for further comparison. Furthermore, a future study can be done for other islands to make comparison across themselves.

This study has shown that although North Cyprus suffers from political problems and drought in the agriculture sector, this sector still has an impact on the economy. Thus, effective policies related with this sector should be developed by authorities. Building pipelines from Turkey, which are at the agenda of North Cyprus and Turkish governments over the years should immediately put into action. This will have enormous impact on both sides of the island on the way to a solution in Cyprus problem.

This study is the first of its kind which analyzes the relationship between agricultural output and economic growth in a small island which has a closed economy and is politically non‐recognized state. Furthermore, it is a rare study made for small islands.