Ioannis Markoulidakis

Dr. Ioannis Markoulidakis

Dr
orcid

Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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2 November 2021 in Technologies
Verified
Journal Article
Open access
PDF file
Ioannis MarkoulidakisIoannis Markoulidakis
Ioannis Markoulidakis
IRIoannis Rallis
Ioannis Rallis
IGIoannis Georgoulas
Ioannis Georgoulas
GKGeorge Kopsiaftis
George Kopsiaftis
NDNikolaos Doulamis
Nikolaos Doulamis
NDNikolaos Doulamis
Nikolaos Doulamis
The current paper presents a novel method for reducing a multiclass confusion matrix into a 2×2 version enabling the exploitation of the relevant performance metrics and methods such as the receiver operating characteristic and area under the curve for the assessment of different classification algorithms. The reduction method is based on class grouping and leads to a special type of matrix called the reduced confusion matrix. The developed method is then exploited for the assessment of state of the art machine learning algorithms applied on the net promoter score classification problem in the field of customer experience analytics indicating the value of the proposed method in real world classification problems.

13 July 2024 in Technologies
Verified
Journal Article
Open access
PDF file
Ioannis MarkoulidakisIoannis Markoulidakis
Ioannis Markoulidakis
GMGeorgios Ioannis Markoulidakis
Georgios Ioannis Markoulidakis
The paper addresses the issue of classification machine learning algorithm performance based on a novel probabilistic confusion matrix concept. The paper develops a theoretical framework which associates the proposed confusion matrix and the resulting performance metrics with the regular confusion matrix. The theoretical results are verified based on a wide variety of real-world classification problems and state-of-the-art machine learning algorithms. Based on the properties of the probabilistic confusion matrix, the paper then highlights the benefits of using the proposed concept both during the training phase and the application phase of a classification machine learning algorithm.

7 December 2020 in Technologies
Verified
Journal Article
Open access
PDF file
Ioannis MarkoulidakisIoannis Markoulidakis
Ioannis Markoulidakis
IRIoannis Rallis
Ioannis Rallis
IGIoannis Georgoulas
Ioannis Georgoulas
GKGeorge Kopsiaftis
George Kopsiaftis
NDNikolaos Doulamis
Nikolaos Doulamis
Anastasios DoulamisAnastasios Doulamis
Anastasios Doulamis
Customer Experience (CX) is monitored through market research surveys, based on metrics like the Net Promoter Score (NPS) and the customer satisfaction for certain experience attributes (e.g., call center, website, billing, service quality, tariff plan). The objective of companies is to maximize NPS through the improvement of the most important CX attributes. However, statistical analysis suggests that there is a lack of clear and accurate association between NPS and the CX attributes’ scores. In this paper, we address the aforementioned deficiency using a novel classification approach, which was developed based on logistic regression and tested with several state-of-the-art machine learning (ML) algorithms. The proposed method was applied on an extended data set from the telecommunication sector and the results were quite promising, showing a significant improvement in most statistical metrics.

26 June 2024
Verified
Conference Paper
Open access
GKGeorge Kopsiaftis
George Kopsiaftis
IKIason Katsamenis
Iason Katsamenis
IRIoannis Rallis
Ioannis Rallis
NBNikolaos Bakalos
Nikolaos Bakalos
CZCharalampos Zafeiropoulos
Charalampos Zafeiropoulos
SCStephanos Camarinopoulos
Stephanos Camarinopoulos
In recent years, there has been a notable rise in the adoption of Unmanned Aerial Vehicles (UAVs) for infrastructure inspection. This study focuses on presenting IKAROS, an integrated system that harnesses the combined capabilities of multiple UAVs and deep learning (DL) tools to improve the efficiency of road transport network inspections, facilitate the detection of road defects, and manage traffic emergencies. Specifically, we introduce the IKAROS system, outlining its key components and functionalities, with a particular emphasis on the applied technologies and the interconnections of its various systems. In addition, we provide an overview of the pilot site and address the challenges associated with real-world implementation.