This thesis is comprised of five papers that all relate to bootstrap methodology in analysis of non-stationary time series. The first paper starts with the fact that the Dickey-Fuller unit root test using asymptotic critical value has bad small sample performance. The small sample correction proposed by Johansen (2004) and bootstrap are two effective methods to improve the performance of the test. In this paper we compare these two methods as well as analyse the effect of bias-adjusting through a simulation study. We consider AR(1) and AR(2) models and both size and power properties are investigated. The second paper studies the asymptotic refinement of the bootstrap cointegration rank test. We expand the test statistic of a simplified VECM model and a Monte Carlo simulation was carried out to verify that the bootstrap test gives asymptotic refinement. The third paper focuses on the number of bootstrap replicates in bootstrap Dickey-Fuller unit root test. Through a simulation study, we find that a small number of bootstrap replicates are sufficient for a precise size, but, with too small number of replicates, we will lose power when the null hypothesis is not true. The fourth and last paper of the thesis concerns unit root test in panel setting focusing on the test proposed by Palm, Smeekes and Urbain (2011). In the fourth paper, we study the robustness of the PSU test with comparison with two representative tests from the second generation panel unit root tests. In the last paper, we generalise the PSU test to the model with deterministic terms. Two different methods are proposed to deal with the deterministic terms, and the asymptotic validity of the bootstrap procedure is theoretically checked. The small sample properties are studied by simulations and the paper is concluded by an empirical example. / <p>Ogiltigt ISBN: 978-91-554-9069-0</p>

This study tests for the market efficiency of the Nairobi Securities Exchange (NSE) after the year 2000 to determine the effect of technological advancements on market efficiency. Data that is used is the NSE 20 share index over the period 2001 to 2015; and the NSE All Share Index (NSE ASI) from its initiation during 2008 to 2015. We cannot accept the Efficient Market Hypothesis (EMH) for the NSE using the serial correlation test, the unit root tests and the runs test. However, we can accept the EMH for the more robust variance ratio test. Overall, the results of the market efficiency are mixed. The most significant finding is that the efficiency of the NSE has increased since the year 2000 which suggests that advancements in technology have contributed to the increase in the market efficiency of the NSE. / Business Management / M. Com. (Business Management)

The purpose of this study is to research the volume-price relationship and information transmission among Taiwan Stock Index, Electronic Industry Index, Financial Industry Index and Plastic Industry Index. This study uses the time series methods of ADF unit root test, variance decomposition, Granger causality and impulse response analysis to proceed empirical research. It covers the period June 2, 2003, through December 29, 2006 and uses the daily data for sample. The empirical results can be summarized as follows¡G (1) All the trading volume and stock return series are trend stationary at level, therefore, they are integrated of order 0 ~ I (0). (2) The variance decomposition shows that the major change of every variable comes from by itself. The explanatory power of trading volume is higher than stock returns. Among the stock returns of Taiwan Stock Index, Electronic Industry Index, Financial Industry Index and Plastic Industry Index, Taiwan Stock Index has the highest explanatory power. (3) According to the Granger causality test, it expresses that trading volume leads stock returns. Taiwan Stock Index is the leading indicator of the Electronic Industry Index and Financial Industry Index. (4) As to the impulse response functions, neither persistent nor overall. The effect of shocks on all variables is transitory.

Purchasing Power Parity (PPP) is an important theory of exchange rate determination. The documents probing into the PPP theory are voluminous nowadays; however, there hasn¡¦t been an agreed conclusion yet. In this paper, we apply the Panel Lagrange Multiplier unit root test, a newly developed panel unit root test that allows for heterogeneous breaks, under both the null and the alternative, in both the level and trend of the series under investigation, addressed by Im, Lee and Tieslau (2010). The validity of PPP theory can be examined by testing the stationary of real exchange rates. We use the data chosen from the countries of Asia, including Taiwan, Japan, Korea, Tailand, Indonesia, Hong Kong and Singapore to proceed the positive analysis. The result shows that no matter we use CPI or WPI as the price index, both considering more about the structure breaks and using the panel unit root test strongly support the PPP theory. And it also shows that when using the WPI as the price index, there would be much more countries support the PPP theory.

This paper is based on international trade between Taiwan and China intently. This purpose of this paper is to explore economic factors on the volume of Phalaenopsis orchid export from Taiwan to China from 1998 to 2011 . This paper will firstly set four influence variables, the previous export, the China's GDP, the exchange rate and the tariff . Then, this paper will exam those variables by using Unit Root test and the Vector Autoregressive (VAR) method in an empirical analysis. After the examination by Unit Root test, the result shows that all the variables appear to be stationary in the first difference. Furthermore, in Chow test, the empirical results indicate that no structural change occurred before and after the first phase of tariff reduction under ECFA. In co-integration test, those variables are co-integrated. In VAR model, China¡¦s GDP, the exchange rate, and the tariff have impact on the volume of the imports from Taiwan to China in different degrees as well.

Using the monthly data between 1999 and 2007 in Taiwan, we examine the relationship of exchange rate, trade and capital flow in this paper. Granger causality test and impulse response from vector autoregressive model are employed to obtain the short-run dynamics among the variables, and Johansen cointegration test and error correction model are applied to study the long-run equilibrium. This paper reconfirms the J-curve effect in the short run and the validity of Marshall-Lerner condition in the long run. Our results also show the negative correlation of capital flow and the nominal effective exchange rate. Limited by the slow adjustment speed of trade balance, exchange rate and capital flow are the major drives back to equilibrium when the system deviates from the long-run equilibrium. Further, the capital flow variables are the leading indicators of the others in the most cases. However, different capital flow variables induce different patterns of dynamics in the short-run.

The main purpose of this thesis is to explore whether the Balassa-Samuelson hypothesis can effectively explain the long-term change of the real exchange. The recent panel unit root, panel cointegration tests and fully modified OLS are applied to examine the four tested equations that are based on the Balassa-Samuelson hypothesis. 1. Relative differential productivity between traded and non-traded sectors influences price differential in two sectors. 2. We extend the relative productivity in non-traded and traded sectors causing change in non-traded relative price into the two-country model. 3. The appreciation (depreciation) of the real exchange results from the different relative price of the two-country model. 4. The appreciation (depreciation) of the real exchange is caused by the different relative productivity of the two-country model. The data span is from 1971 to 1995, and includes 12 OECD countries. There are three main different points from the existing literatures. 1. We apply some newly developed panel unit root tests to estimate the equations based on Balassa-Samuelson hypothesis. 2. The previous documents only estimated the model of one variable, but the estimation of two variables was rare. In the equation 14 and 15, we examined the two variables in both. 3. In the calculation of the price, owing to the difficulties of collecting data from various sectors, we use a special way to measure the price. Finally, we can observe from the results of the empirical study: when productivity of the domestic sectors differentiates, that is, 1% increase in relative productivity between traded and non-trade sectors causes 0.53% increase in domestic relative prices. When it is taken into the two-country model, the increase of productivity will cause the appreciation of the real exchange rate. This can explain why in the developed countries like the U.S. and Japan, the faster increase in domestic relative productivity causes the appreciation of real exchange rates in the long run.

The main purpose of this thesis is to explore whether the Balassa-Samuelson hypothesis can effectively explain the long-term change of the real exchange. The recent panel unit root, panel cointegration tests and fully modified OLS are applied to examine the four tested equations that are based on the Balassa-Samuelson hypothesis. The data span is from 1985 to 2002, and includes 7 east asian countries. 1. Relative differential productivity between traded and non-traded sectors influences price differential in two sectors. 2. We extend the relative productivity in non-traded and traded sectors causing change in non-traded relative price into the two-country model. 3. The appreciation (depreciation) of the real exchange results from the different relative price of the two-country model. 4. The appreciation (depreciation) of the real exchange is caused by the different relative productivity of the two-country model. Finally, we can observe from the results of the empirical study: when productivity of the domestic sectors differentiates, that is, 1% increase in relative productivity between traded and non-trade sectors causes 0.28% increase in domestic relative prices. When it is taken into the two-country model, the increase of productivity will cause the appreciation of the real exchange rate.

There are much economic and financial data which are restricted by some bounds, such as expenditure shares, unemployment, norminal interest rate, or target zone exchange rate. How to interpret and analyze time series whose behaviors can be well approximated by means of integrated processes, I(1), but are ¡§limited¡¨ in the sense that their range is constrained by fixed bounded is what this thesis develops. One method to analyze bounded variable of this paper is ¡§The Bounded Unit Root¡¨ which provided by Cavaliere (2005), and the other is using Gibbs sampling simulation and trying to recover the part of hidden variables. We would examin some empirical problems that has often been tackled in the literature and we give three time series which include Danish kron/Deutshe mark, Belgium Franc/ Deutshe mark, and Japan 1 mouth interbank interest rate for examples. We conclude that these three time series data are I(0) in classical unit root test framework, but are all I(1) in The Bounded Unit Root test framework. And the results of Gibbs sampling simulation are that Danish kron/Deutshe mark and Belgium Franc/ Deutshe mark are I(0), but Japan 1 mouth interbank interest rate is I(1).

Factors such as economical development, rapid increase in population and climate change increased electricity demand in Turkey as well as in other countries. Thus, using the correct methods to estimate short, medium and long term electricity demand forms a basis for the countries to develop their energy strategy. In this study, monthly electricity demand of Turkey is estimated. First, the effect of natural gas price and consumption to electricity demand and elasticities are searched with a simple regression model. Although, natural gas is known as a substitute of electricity, natural gas consumption and natural gas over electricity price ratio are found to be nearly inelastic. Second part includes two models and cointegration relation is investigated in nonstationary industry production index, electricity consumption per capita and electricity prices series in the first one. An error correction model is then formed with an additional average temperature variable and 12 months electricity demand is forecasted. In the second one, heating degree-days and cooling degree-days are used instead of the average temperature variable and a new error correction model is formed. The first model performs better than the second one, indicating the seasonality of electricity consumption during a year. The results of both models are also compared with previous studies to investigate the effect of different weather variables.