A population dependent diffusion model with a stochastic extension

Diffusion modeling is rather broad in nature, and is important in the areas of estimation and forecasting. Conventional models do not incorporate parameters that explicitly take into account the size of the population, or, equivalently, the size of the potential market. As a consequence, the models often fail to provide accurate forecasts, especially when the diffusion process is in the take-off stage. Furthermore, since diffusion is not a strictly deterministic process, forecasts should provide a measure of the underlying uncertainty of the process by incorporating a stochastic process into the formulation of the models. The aim of the present work is to fill this gap by proposing an aggregate diffusion model, the "population" diffusion model (PDM), which incorporates the potentially varying market size as a function of the corresponding population. This model realization provides more accurate estimations and future forecasts of the diffusion process, especially when compared to the conventional aggregate diffusion models. © 2012

On the combination of exponential smoothing and diffusion forecasts: An application to broadband diffusion in the OECD area

The innovation diffusion literature has established that the spread of a successful innovation over time typically follows a sigmoid curve. Therefore, the forecasting in this area has been monopolized by the use of well known aggregate diffusion models. Time series forecasting has been surprisingly neglected, as it provides mainly accurate short term forecasts. In this work, a method of exponential smoothing, the Holt's damped trend with a modification, is applied in recent broadband diffusion data of two large regions after the reach of the inflection point. As validated with holdback sample data ranging from 6 up to 30. months, the key for successful forecasting is the use of the estimated saturation level calculated from a diffusion model, in order to specify the appropriate trend. The results indicate improved predictions compared to two popular diffusion models, the Gompertz and the Linear Logistic model. The paper concludes with the application of the proposed method in a 48-month forecasting horizon, as well as the suggestions for further research. © 2010 Elsevier Inc

Innovation diffusion with generation substitution effects

Markets of high technology products and services, such as telecommunications, are described by fast technological changes and rapid generational substitutions. Since the conventional modeling approaches that are based on diffusion models do not usually incorporate this important aspect into their formulations, the accuracy of the provided forecasts is consequently affected. The work presented in this paper is concerned with the development of a methodology for describing innovation diffusion, in the context of generation substitution. For this purpose, a dynamic diffusion model is developed and evaluated, based on the assumption that the saturation level of the market does not remain constant throughout the diffusion process but is affected by the diffusion of its descendant generation, as soon as the latter is introduced into the market. In contradiction to the conventional diffusion models, which assume static saturation levels, the proposed approach incorporates the effects of generation substitution and develops a diffusion model with a dynamic ceiling. The importance of such an approach is especially significant for markets characterized by rapid technological and generational changes. Evaluation of the proposed methodology was performed over 2G and 3G historical data and for a number of European countries, providing quite accurate estimation and forecasting results, along with important information regarding the rate of generation substitution. © 2009 Elsevier Inc

Forecasting with limited data: Combining ARIMA and diffusion models

Forecasting diffusion of new technologies is usually performed by the means of aggregate diffusion models, which tend to monopolize this area of research and practice, making the alternative approaches, like the Box-Jenkins, less favourable choices due to their lack of providing accurate long-term predictions. This paper presents a new methodology focusing on the improvement of the short-term prediction that combines the advantages of both approaches and that can be applied in the early stages of a diffusion process. An application of the methodology is also illustrated, providing short-term forecasts for the world broadband and mobile telecommunications' penetration. The results reveal that the methodology is capable of producing improved one-year-ahead predictions, after a certain level of penetration, as compared to the results of both methods individually. This methodology can find applications to all cases of the high-technology market, where a diffusion model is usually used for obtaining future forecasts. The paper concludes with the limitations of the methodology, the discussion on the application's results and the proposals for further research. © 2010 Elsevier Inc

Digital divide gap convergence in Europe

The diffusion of broadband in Europe is shaped by the penetration rates of the individual European countries. However, the contribution of each country to the total level of diffusion is not the same, due to the existence of a digital divide among the countries. The digital divide is still evident and although diffusion keeps increasing, not all countries have the same rate of broadband adoption. Based on the above, a methodology measuring the digital divide gap is presented in the context of this research, together with forecasts regarding broadband convergence. Evaluation of the methodology was performed for the European countries examined from 2001 to 2009. © 2011 Elsevier Ltd

Modeling competition in the telecommunications market based on concepts of population biology

Based on concepts of ecology modeling and specifically on population biology, a methodology for describing a high-technology markets dynamics is developed and presented. The importance of the aforementioned methodology is its capability to estimate and forecast the degree of competition, market equilibrium, and market concentration, the latter expressed by corresponding market shares, in the high-technology environment. Evaluation of the presented methodology in the area of telecommunications led to accurate results, as compared to historical data, in a specific case study. Apart from a very good estimation of the markets behavior, this methodology presents a very good forecasting ability, which can provide valuable inputs for managerial and regulatory decisions and strategic planning, to the players of a high-technology market, described by high entry barriers. © 2011 IEEE

Broadband penetration as an economic growth accelerator

Under the present economic recession, much discussion is made regarding income increase. New technologies and broadband communications in particular can yield comparative advantages in countries. Based on the assumption that income increase is related to broadband penetration, a Granger causality test is applied in 86 countries worldwide. The causality case is tested separately over developed and developing countries, according to their level of broadband penetration. The analysis is aimed to examine the relationship (one-way or bidirectional) between gross national income per capita and broadband penetration level. Copyright © 2015 Inderscience Enterprises Ltd

Assessment of information and communications technology maturity level

The use of information and communications technology (ICT) turned out to be a key factor in the process of the wider development of a country. It is therefore very useful to estimate ICT evolution by the means of an appropriate metric. Based on statistical data from 159 countries, the ICT maturity level index (IMLI) is proposed and estimated by using structural equation modelling (SEM). This index is a metric measuring the information society in a country and consists of three sub-indices which are access, use and skills. It is an improvement of the ICT development index, proposed by the ITU in 2009. The analysis divides the countries into two groups, the developed and the developing, due to major disparities in their statistical data. The criterion used to define the groups was the income, as expressed by the Gross National Income per capita. The impact of a number of influential parameters on the ICT maturity level is evaluated and it becomes obvious that there is a substantial difference in their impact between developed and developing countries. Finally, a procedure that allows the ranking of the countries, based on IMLI, is presented. © 2012 Elsevier Ltd. All rights reserved

Driving factors during the different stages of broadband diffusion: A non-parametric approach

A number of socio-economic factors influence broadband diffusion and are assumed to be responsible for the different levels of adoption among countries. Most of the approaches met in literature do not take into account the different stages of the diffusion process and they are parametric. They are based on the construction and study of econometric models, which include all the influential parameters. Regression functions are defined prior to the analysis and they are usually linear in nature. However, this increases the complexity of the system, since the less influential variables are derived during the final stages of the analysis. On the contrary, non-parametric methods can achieve dimension reduction during the early stages, while they do not require a definition of the regression function.The present work studies the effect of a wide range of social, economic and political factors over the broadband diffusion process, following a non-parametric approach and comparing the results with these of the parametric. Based on criteria from information theory the link function between the level of penetration and the rest variables is derived, providing highly accurate results. The evaluation of the methodology was performed over countries from the wider European area. It is proven that the different stages of broadband diffusion process, defined by the inflection point, are affected by different factors. © 2012 Elsevier Inc