Cointegration,dynamic structure,and the validity of purchasing power parity in African countries

The purpose of this paper is to test the validity of the purchasing power parity (PPP) in Africa in the context of a multivariate error-correction model. This approach allows for the consideration of long-run elasticities as well as the dynamics of the short-run adjustment of exchange rates to changes in domestic and foreign prices. Monthly data for fourteen African countries are used, and the period examined is 1973:4 through 2007:7 (i.e., 412 observations). Results from long-run cointegration analysis, short-run error correction models, persistence profile analysis and variance decomposition all confirm the validity of PPP in these moderate-to-high inflation countries, where estimates of half-life deviations from PPP are found to be outside the range suggested by Rogoff (1996).     

An object-oriented optimal savings system: HYPER-SAVINGS

This research develops an intelligent dynamic savings investment system called HYPER-SAVINGS which can construct the best savings portfolio embracing all types of products from multiple banks. Since the major model in HYPER-SAVINGS is the 0–1 integer programming (IP) model, we need to interpret information about investors, products, institutions and the current financial situation for the formulation of the IP model. This has become possible by adopting the knowledge-based integer programming modeling aid, UNIK-IP, which allows the formulation of an IP model at a semantic level using logical operators such as EITHER–OR and IF–THEN, and automatically transforms them to a so-called base level model which can be solved by the IP solver. HYPER-SAVINGS also provides the capability of sensitivity analysis at a semantic level to adjust to dynamic situational changes. Since the system is expected to collect the information from various banks through the Internet and filters out dominated products before formulation, HYPER-SAVINGS can provide the architecture for the international meta-bank on the Internet. © 1997 John Wiley & Sons, Ltd.     

Economic evaluation of rituximab in addition to standard of care chemotherapy for adult patients with acute lymphoblastic leukemia

Aims: Acute lymphoblastic leukemia (ALL) is an aggressive form of leukemia with a poor prognosis in adult patients. The addition of the monoclonal antibody rituximab to standard chemotherapy has been shown to improve survival in adults with ALL. However, it is unknown whether the addition of rituximab is cost-effective. The objective was to determine the economic impact of rituximab in addition to standard of care (SOC) chemotherapy vs SOC alone in newly-diagnosed Philadelphia chromosome-negative, CD20-positive, B-cell precursor ALL.

Methods: A decision analytic model was constructed, based upon the Canadian healthcare system. It included the following health states over a lifetime horizon (max ≈60 years): event-free survival (EFS), relapsed/resistant disease, cure, and death. SOC was either hyper-CVAD or the Dana Farber Cancer Institute (DFCI) ALL consortium. EFS, overall survival, and serious adverse event (SAE) rates were derived from a large randomized controlled trial. Costs of the model included: first-line treatment and administration, disease management, second-line and third-line treatment and administration, palliative care, and SAE-related treatments. Inputs were sourced from provincial and national public data, the literature, and cancer agency input.

Results: Quality-adjusted life-years (QALYs) increased by 2.20 QALYs with rituximab in addition to SOC. The resulting mean Incremental Cost-Effectiveness Ratio (ICER) was C$21,828/QALY. At a willingness-to-pay threshold of C$100,000/QALY, the probability of being cost-effective was 98%. Decision outcomes were robust to the probabilistic and deterministic sensitivity analyses, including the SOC backbone as either hyper-CVAD or DFCI.

Limitations: The results of this analysis are limited by generalizability of the chemotherapy backbone to Canadian practice.

Conclusions: For adults with ALL, rituximab in addition to SOC was found to be a cost-effective intervention, compared to SOC alone. The addition of rituximab is associated with increased life years and increased QALYs at a reasonable incremental cost.     

Measuring the Impact of Doi Moi on Vietnam's Gross Domestic Product

In 1986 a wide range of policy measures, known as Doi Moi, was introduced to promote Vietnam's transition to a market economy. This paper represents the first attempt to measure the effect of Doi Moi on Vietnam's GDP. In the paper the level of GDP actually reached is compared with the level that would have been reached had the policy not been implemented, i.e. without the improvements in productivity and the increases in investment ratio that can be directly attributed to Doi Moi. Cross-time changes in GDP were depicted by a production function of capital stock, economically active labour force and technical progress. It was found that, after a time lag, Doi Moi appeared to have a significant positive effect on productivity, which by 1998 accounted for a 42% increase in GDP.     

TACTICAL ASSET ALLOCATION: CAN IT WORK?

Market events of the past ten years have sparked an interest in tactical asset allocation. In the current study we develop and test a model that incorporates currently available information into the tactical asset allocation process. The model provides an estimate of the probabilities that the upcoming market period will be bullish or bearish. Logit analysis is employed to determine which of the various timely and readily available data significantly affect these probabilities. These estimated probabilities are used to suggest the optimal allocations of funds over time between the risk-free asset and the market portfolio. Then, several timing strategies are compared with a buy-and-hold portfolio. An asset allocation strategy based on the probabilities assigned by the logit model appears to achieve greater terminal wealth with less variability of returns. Similar results are obtained for both an initial sample (1962–76 in our model) and a holdout sample (1977–88).     

The time difference effect of a measurement unit in the lead-lag relationship analysis of Korean financial market

This paper investigates Korean financial markets for the study of market microstructure of price discovery in the KOSPI 200 stock index and its related derivatives markets using different time-interval price data. The Granger causality test and vector error correction model are used to analyze the empirical relationship between markets. The lead-lag relationship between the KOSPI 200 stock index and its derivatives markets can be supported by the trading cost hypothesis and leverage effect hypothesis. This paper also shows the congruent lead-lag results in various time-intervals, but as the time-interval becomes large, more information loss and spurious results are induced. The correlations among 1-minute data, 5-minute data, and 10-minute data are significant under a 1% significance level, however, in the case of 60-minute data, the correlations with any other time-interval data are not significant. The 60-minute data even have negative correlations with others. These results are consistent regardless of the raw data or the innovation data. Therefore, we can conclude that the previous research using the 60-minute data due to an insufficiency of trading volume can be biased considerably.     

Whose voice is it anyway? Rethinking the oral history method in accounting research on race, ethnicity and gender

Drawing on contemporary feminist and postcolonial writings, this paper endeavors to provide a critique of some underlying assumptions of the oral history method. The very methodology of the oral history method re-enforces hegemonic Western ideologies about race/ethnicity, gender and class perpetuated through the connection between the cultural identity of the speaker and the notion of authenticity as a ground for academic authority. Without recognizing the inherent subjectivities of the research methods we use, we may unwittingly perpetuate these hegemonic ideologies, despite our good intention. If other histories are to be heard, this bias and viewpoint needs to be challenged, not in a threatening way but in an enlightening way, so that the “Other” voices can tell their stories in a more, if not fully, liberated way.     

On the existence of an implementable optimal income tax

Summary. This paper discusses the existence of an optimal income tax and distinguishes itself from the previous articles in two respects. In previous papers, the self selection condition was not necessarily consistent with the individual budget constraint. Furthermore, implementability in previous papers was implicit in individual ability, rather than individual income, as the basis of the tax function. We offer a different concept of the self selection conditions: Anti Normal Envy that is consistent with the individual budget constraint and that we show to be equivalent to the competitive equilibrium under a tax function based on income. We then establish the existence of an implementable optimal income tax.Received: 9 December 2000, Revised: 5 August 2003, JEL Classification Numbers: H21, C62, D59.Correspondence to: Jun IritaniThe authors are grateful to an anonymous referee of this journal whose suggestions were instrumental to our revision of the paper, and to Professors Takao Kataoka, Tomoyuki Kamo, Tetsuya Kishimoto, and Mototsugu Fukushige, and the members of the Kobe-Osaka Joint Seminar in Mathematical Economics, for their invaluable comments.     

APPLICATIONS OF BEHAVIOURAL ECONOMICS TO TAX EVASION

The paper reviews recent models that have applied the techniques of behavioural economics to the analysis of the tax compliance choice of an individual taxpayer. The construction of these models is motivated by the failure of the Yitzhaki version of the Allingham–Sandmo model to predict correctly the proportion of taxpayers who will evade and the effect of an increase in the tax rate upon the chosen level of evasion. Recent approaches have applied non‐expected utility theory to the compliance decision and have addressed social interaction. The models we describe are able to match the observed extent of evasion and correctly predict the tax effect but do not have the parsimony or precision of the Yitzhaki model.