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Book Chapter

2023

On the Selection of Power Transformation Parameters in Regression Analysis

2023-12-27
In multiple linear regression, there are several classical methods used to estimate the parameters of power transformation models that are used to transform the response variable. Traditionally, these parameters can be estimated using either Maximum Likelihood Estimation or Bayesian methods in conjunction with the other model parameters. In this chapter, attention has been paid to four indicators of the efficiency and reliability of the regressive modeling, and study the possibility of considering them as decision rules through which the optimal power parameter can be chosen. The indicators are the coefficient of determination and p-value of the general linear F-test statistic. Also, the p-value of Shapiro-Wilk test (SWT) statistic for the residual’s normality of the estimated linear regression of the transformed response vector and the estimated nonlinear regression of the original response vector resulting from the back transform of the power Transformation model. Real data were used and a computational algorithm was proposed to estimate the optimal power parameter. The authors concluded that the multiplicity of indicators does not lead to obtaining an optimal single value for the power parameter, but this multiplicity may be useful in fortifying the decision-making ability.
2022

A New Approach for Power Transformations in Functional Non-Parametric Temperature Time Series. DOI: 10.5772/intechopen.105832

2022-07-22
In nonparametric analyzes, many authors indicate that the kernel density functions work well when the variable close to the Gaussian shape. This chapter is interested with the improvement the forcasetability of the functional nonparametric time series by using a new approach of the parametric power transformation. The choice of the power parameter in this approach is based on minimizing the mean integrated square error of kernel estimation. Many authors have used this criterion in estimating density under the assumption that the original data follow a known probability distribution. In this chapter, the authors assumed that the original data were of unknown distribution and set the theoretical framework to derive a criterion for estimating the power parameter and proposed an application algorithm in two-time series of temperature monthly averages.
2009

Market Assessment; Business constraints and opportunities at the business enabling environment and firm levels. A survey of small enterprises in Iraq, Project Senior Technical Assistant. USAID. https://pdf.usaid.gov/pdf_docs/PNADX181.pdf

2009-11-19
Anbar makes up about one-third of Iraq's land mass, but only about 5% of its population. The population is distributed unevenly, with major urban centers such as Fallujah, Ramadi, and Haditha in its north eastern and eastern areas, and a vast and sparsely populated desert area to the west of the cities. The greater Fallujah and Ramadi areas alone account for 70% of the population. Hence, Anbar really “behaves” like two provinces, with light manufacturing and transportation in more populated areas and agriculture dominating its surrounds and all the western areas. This geographical diversity and remoteness, combined with Anbar‟s low computer usage, creates service delivery and transportation issues in areas that need significant BDS support. The violence that has characterized much of Anbar's recent history has marked its current SME business culture, economy, and workforce. That workforce is more youthful and less well trained than for Iraq as a whole. More important, suspicions about central government control which antedated the fall of Saddam have been so exacerbated by Anbar‟s violent past that the kinds of formal private (eg. BMO) and public institutions necessary for transforming business life in Anbar remain basically unused. Any plan for delivering BDS services must take family and tribal values, plus lack of trust of formal organization and institutional action into consideration. Building a public presence with be a slow process requiring careful attention to Anbar‟s history and cultural norms. Anbar's economy swings between an almost entirely informal horticultural system that isboth aging and declining, and a highly formalized transportation sector that is both "new" and expanding. Help for the declining date growing culture is important but dates are grown in remote areas that are both difficult to service and create distribution concerns exacerbated by security. Other agricultural activities once dependent on channel irrigation from the Euphrates have been disrupted, and uncertain electrical supply will inhibit the growth of pump-driven replacement systems. There is a free trade zone at Al-Qaim, but it is in need of development before it can be of any significant impact on the local or provincial economy.
2007

Kurdistan Business Agenda - in three languages - Editing and Writing - Center for International Private Enterprise CIPE. https://www.researchgate.net/publication/340582651_Kurdistan_Business_Agenda

2007-07-11
Different business sectors have diverse needs that fall, directly or indirectly and to varying degrees, within the state’s scope of responsibilities. These sectors cannot achieve advanced productivity levels unless a minimum set of these needs are met. While each sector has its own specific concerns, there are common problems and challenges that most of them face. The Supervisory Committee, responsible for the final review of the Agenda, chose to have a separate file for these common challenges that were repeated in almost all of the eleven files that agenda coordinators had prepared. The large overlap and interdependence among different sectors’ economic activities necessitates that all those concerned with economic affairs at the governmental and business levels consider all sectors in a balanced manner in order to maximize production and optimize resources utilization across all sectors. In the same context, interdependent sectors face a series of similar problems that impede continued economic activity. For example, one of the main issues of the housing and contracting sector is the desire to re-zone agricultural land to residential land. Those concerned with the agricultural sector perceived the issue from a different perspective and do not want agricultural land to be re-zoned into residential land. The tourism sector agenda included similar demands. Although such conflicts reflect the norm of competition—where each party defends those rights they perceive to result in increased profits—they also assert the need for regulation and oversight in civil life and in business, hence the need to comprehend all relevant administrative elements. This is a decisive factor in determining the basis for balancing these needs, and the aforementioned disagreements comprise just one example of many such divergent interests. The most important conclusion in this section is the existence of large overlaps between various business sectors and their needs, which necessitates the formulation of a wide-scale and long-term strategic vision that defines priorities and creates a solid foundation for resolving such problems. This section presents the common problems of business sectors. Further details on the impact of each problem on these sectors, as well as proposed solutions by principal parties for each sector, are presented in the subsequent sections.

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