Forecasting Construction Tender Price Index in Ghana using Autoregressive Integrated Moving Average with Exogenous Variables Model

Prices of construction resources keep on fluctuating due to unstable economic situations that have been experienced over the years. Clients knowledge of their financial commitments toward their intended project remains the basis for their final decision. The use of construction tender price index provides a realistic estimate at the early stage of the project. Tender price index (TPI) is influenced by various economic factors, hence there are several statistical techniques that have been employed in forecasting. Some of these include regression, time series, vector error correction among others. However, in recent times the integrated modelling approach is gaining popularity due to its ability to give powerful predictive accuracy. Thus, in line with this assumption, the aim of this study is to apply autoregressive integrated moving average with exogenous variables (ARIMAX) in modelling TPI. The results showed that ARIMAX model has a better predictive ability than the use of the single approach. The study further confirms the earlier position of previous research of the need to use the integrated model technique in forecasting TPI. This model will assist practitioners to forecast the future values of tender price index. Although the study focuses on the Ghanaian economy, the findings can be broadly applicable to other developing countries which share similar economic characteristics

The influence of project complexity on estimating accuracy

With the rapid development in technology over recent years, construction, in common with many areas of industry, has become increasingly complex. It would, therefore, seem to be important to develop and extend the understanding of complexity so that industry in general and in this case the construction industry can work with greater accuracy and efficiency to provide clients with a better service. This paper aims to generate a definition of complexity and a method for its measurement in order to assess its influence upon the accuracy of the quantity surveying profession in UK new build office construction. Quantitative data came from an analysis of twenty projects of varying size and value and qualitative data came from interviews with professional quantity surveyors. The findings highlight the difficulty in defining and measuring project complexity. The correlation between accuracy and complexity was not straightforward, being subjected to many extraneous variables, particularly the impact of project size. Further research is required to develop a better measure of complexity. This is in order to improve the response of quantity surveyors, so that an appropriate level of effort can be applied to individual projects, permitting greater accuracy and enabling better resource planning within the profession

The reliability of macro-economic forecasts

In Germany since early 1981 a consensus has emerged predicting that an economic recovery is due for the second half of the year. This forecast of an upturn was put-forth for 1981 and for 1982. Despite these consensus, the forecasts proved to be wrong. Nonetheless in autumn 1982 the consensus forecast for 1983 again explicitly included a recovery starting mid-year, and again the forecast seems to be proving to be wrong. This time, however, the failure is not forecasting a recovery, only to find out its not there, but rather miscalculating in the other direction as the economic recovery has already been' on the move since the beginning of 1983.

Optimal allotment policy in the Eurosystem's main refinancing operations

On several occasions during the period 2001-2003, the European Central Bank (ECB) decided to deviate from its “neutral” benchmark allotment rule, with the effect of not alleviating a temporary liquidity shortage in the banking system. This is remarkable because it implied the possibility of short-term interest rates raising significantly above the main policy rate. In the present paper, we show that when the monetary authority cares for both liquidity and interest rate conditions, the optimal allotment policy may entail a discontinuous reaction to initial conditions. More precisely, we prove that there is a threshold level for the accumulated aggregate liquidity position in the banking system prior to the last operation in a given maintenance period, so that the benchmark allotment is optimal whenever liquidity conditions are above the threshold, and a tight allotment is optimal whenever liquidity conditions are below the threshold. JEL Classification: E43, E52euro, monetary policy instruments, operational framework, refinancing operations-

Analysis of tender sum forecasting by quantity surveyors and contractors in South Africa

Although extensive research has been undertaken on the accuracy of quantity surveyors' tender price forecasts, very little of this research contains information relating to the factors affecting tender sum forecasting by quantity surveyors and contractors. The primary objective of this empirical study was to gain insight into the factors influencing both quantity surveyors' and contractors' tender price forecasts. This was achieved through an analysis of tender information relating to 278 projects for a fifteen-year period and collected from 30 quantity-surveying practices and MBATA tender records. The analysis of South African tender information reported in this article indicates an average forecast performance by quantity surveyors of 8.33% (std dev (standard deviation) = 11,183, CV (coefficient of variation) = 134,2%). The variability of contractors' tenders ranged from 0,37% to 46,53%, with a mean of 5,65% (std dev = 5,22, SE (standard error) = 0,313). Furthermore, there is no evidence to suggest that forecast performance is dependent on type of project, client, function of project, size of project, location of project and number of bidders. The contractor's results suggest that local authority projects are associated with high variability of their tender sum forecasts. The only factor, which shows significance for quantity surveyors, is the date of tender which may tend to point to the importance of market conditions and economic cycle in the tender sum forecast performance of South African quantity surveyors

Analysis of tender sum forecasting by quantity surveyors and contractors in South Africa

Although extensive research has been undertaken on the accuracy of quantity surveyors' tender price forecasts, very little of this research contains information relating to the factors affecting tender sum forecasting by quantity surveyors and contractors. The primary objective of this empirical study was to gain insight into the factors influencing both quantity surveyors' and contractors' tender price forecasts. This was achieved through an analysis of tender information relating to 278 projects for a fifteen-year period and collected from 30 quantity-surveying practices and MBATA tender records. The analysis of South African tender information reported in this article indicates an average forecast performance by quantity surveyors of 8.33% (std dev (standard deviation) = 11,183, CV (coefficient of variation) = 134,2%). The variability of contractors' tenders ranged from 0,37% to 46,53%, with a mean of 5,65% (std dev = 5,22, SE (standard error) = 0,313). Furthermore, there is no evidence to suggest that forecast performance is dependent on type of project, client, function of project, size of project, location of project and number of bidders. The contractor's results suggest that local authority projects are associated with high variability of their tender sum forecasts. The only factor, which shows significance for quantity surveyors, is the date of tender which may tend to point to the importance of market conditions and economic cycle in the tender sum forecast performance of South African quantity surveyors

Perceived benefits of adopting Standard – Based pricing mechanism for mechanical and electrical services installations

Cost is an important measure of project success and clients will expect a reliable forecast at the early stage of construction projects to inform their business decision. This study was undertaken to investigate the current practices in managing cost of mechanical and electrical (M&E) services in buildings. The perceptions of practitioners on the benefits of adopting Standard – Based Pricing Mechanism for M&E services as used for building fabrics and finishes was ascertained. The methodology adopted for the study was semi – structure interview and questionnaire survey.  Inferential statistics technique was used to analyse the data collected. The results revealed that, M&E services tender documents are often based on lump sum contract. Practitioners are of the opinion that the adoption of Standard – Based Pricing Mechanism (SBPM) could enhance the quality of M&E services price forecast; ensure active post contract cost monitoring and control; encourage collaborative working relationship; enhance efficient whole life cycle cost management; improve risk management and facilitate efficient tendering process. The study suggested the development of local Standard Method of Measurement for M&E services and proposed strategies to facilitate the adoption of SBPM as basis for forecasting contract price of mechanical and electrical services in buildings

Attitudes to Risk and Roulette

We present an empirical framework for determining whether or not customers at the roulette wheel are risk averse or risk loving. Thus, we present a summary of the Aumann-Serrano (2007) risk index as generalized to allow for the presence of risk lovers by Schnytzer and Westreich (2010). We show that, for any gamble, whereas riskiness increases for gambles with positive expected return as the amount placed on a given gamble is increased, the opposite is the case for gambles with negative expected return. Since roulette involves binary gambles, we restrict our attention to such gambles exclusively and derive empirically testable hypotheses. In particular, we show that, all other things being equal, for gambles with a negative expected return, riskiness decreases as the size of the contingent payout increases. On the other hand, riskiness increases if the gamble has a positive expected return. We also prove that, for positive return gambles, riskiness increases, ceteris paribus, in the variance of the gamble while the reverse is true for gambles with negative expected returns. Finally, we apply these results to the specific gambles involved in American roulette and discuss how we might distinguish between casino visitors who are risk averse and those who are risk loving as well as those who may suffer from gambling addictions of one form or another.