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BUKU ABSTRAK - Universiti Putra Malaysia

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New Geometric Approach to Static and Dynamic Measurements of Risk,<br />

Bankruptcy and Market Ranking<br />

Assoc. Prof. Dr. Noor Akma Ibrahim<br />

Alireza Bahiraie, AKM Azhar and Ismail Mohd.<br />

Institute of Mathematical Research, University <strong>Putra</strong> <strong>Malaysia</strong>,<br />

43400 UPM Serdang, Selangor, <strong>Malaysia</strong>.<br />

+603-8946 6873; nakma@putra.upm.edu.my<br />

Semiparametric Modelling of Longitudinal Ordinal Data<br />

Assoc. Prof. Dr. Noor Akma Ibrahim<br />

Suliadi Isa Daud and Isthrinayagy S. Krishnarajah<br />

Institute of Mathematical Research, University <strong>Putra</strong> <strong>Malaysia</strong>,<br />

43400 UPM Serdang, Selangor, <strong>Malaysia</strong>.<br />

+603-8946 6873; nakma@putra.upm.edu.my<br />

201<br />

Science, Technology & Engineering<br />

Recently, geometrics are more frequently used in business, finance, scientific, and engineering applications.<br />

The increasing popularity of geometry is due to its adaptability and simplicity. In this research, a new geometric<br />

methodology for forecasting were developed and implemented. Our new static (Risk Box, RB) and dynamic<br />

(Dynamic Risk Space, DRS) geometric methodology and our new copy righted software (Dynamic Geometric<br />

Risk Space Software, DGRSS) can be used to solve the most important factors when errors are engaged in<br />

financial forecastings. This methodology takes into account every related component of financial predictions. Our<br />

algorithm combined the powerful search of geometric approach and its capability to learn about the relationship<br />

patterns of past data in order to forecast future values. This new geometric forecasting method consists of two<br />

steps: forecasting and learning steps. We used our new geometric indexes in the forecasting step to estimate<br />

parameters of the problem domain. Patterns learning are taken into account in the software algorithm to capture<br />

the patterns relationship of learning data. Then the effectiveness of the methodology is examined by applying<br />

them in bankruptcy prediction field of finance.<br />

Keywords: Geometric approach, risk box, bankrupcty, genetic programming, robust logistic regression<br />

This research considers semiparametric model for longitudinal ordinal data. The model consists of two<br />

components, parametric and nonparametric components. We propose GEE-Smoothing spline to estimate both<br />

components by extending parametric generaliszed estimating equation (GEE) to semiparametric GEE. The<br />

nonparametric component is estimated using smoothing spline while the association parameter is estimated<br />

through another set of estimating equation. We use profile algorithm in the estimation of both components. In this<br />

algorithm, the components are treated in different manner. The properties of the parametric and nonparametric<br />

components of the proposed model are evaluated through simulation study. Both components are consistent<br />

regardless of misspecification of the working correlation. The bias of the parametric component is small and<br />

negligible whereas the nonparametric component is bias. The most efficient estimate for the parametric component<br />

is obtained if the true correlation structure is used and assumed independence results in a less efficient estimate.<br />

The efficiency behaviour of the nonparametric component is different from parametric where the most efficient<br />

estimate is obtained when independence is assumed.<br />

Keywords: Semiparametric equation, longitudinal ordinal data, generalised estimating equation, smoothing spline, property<br />

of estimator

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