This master thesis is concerned with the choice of suitable data quality dimensions for a particular database of economy information and proposes and implements metrics for its assessment. The aim of this paper is to define the term data quality in the context of economy information database and possible ways to measure it. Based on dimensions suitable to observe, a list of metrics was created and subsequently implemented in SQL query language, alternatively in a procedural extension Transact SQL. These metrics were also tested with the use of real data and the results were provided with a commentary. The main asset of this work is its complex processing of the data quality topic, from theoretical term definition to particular implementation of individual metrics. Finally, this study offers a variety of both theoretical and practical directions fort this issue to be further researched.

The master thesis deals with data quality in the context of open and linked data. One of the goals is to define specifics of data quality in this context. The specifics are perceived mainly with orientation to data quality dimensions (i. e. data characteristics which we study in data quality) and possibilities of their measurement. The thesis also defines the effect on data quality that is connected with data transformation to linked data; the effect if defined with consideration to possible risks and benefits that can influence data quality. The list of metrics verified on real data (open linked data published by government institution) is composed for the data quality dimensions that are considered to be relevant in context of open and linked data. The thesis points to the need of recognition of differences that are specific in this context when assessing and managing data quality. At the same time, it offers possibilities for further study of this question and it presents subsequent directions for both theoretical and practical evolution of the topic.

Marine biotoxins constitute one of the major hazards associated with seafood consumption. Risk assessments are essential for the effective management of problems arising from marine biotoxins occurrence, as they are a prerequisite for the establishment or periodic re-evaluation of marine biotoxins regulatory limits and for the adoption of appropriate risk management plans. Risk assessments are science-based data-intensive processes, and their successful outcomes are largely dependent on the quality of data used when they are carried out. In fact, data-related challenges are the most frequently reported issues rendering most marine biotoxins’ risk assessments conducted to date as inconclusive. Notably, data quality perceptions among the stakeholders involved in risk assessments may vary significantly, which may be a human factor influencing data quality. As such, the problem addressed in this thesis is the shortage of empirical information on how data quality is perceived by the different stakeholder roles involved in risk assessments relevant to marine biotoxins hazards. The focus of this thesis is thus to investigate the perceptions of diverse stakeholders within the information chain, namely data producers, collectors and consumers/users, regarding the quality of data used in risk assessments of marine biotoxins hazards, to provide a contribution directed towards data quality improvement. This was done by means of a survey, gathering data through interviewing a number of recognized marine biotoxins’ experts with documented experience in risk assessments. The research question of this study is: “What are the perceptions of data quality among diverse stakeholders along the information chain relevant to marine biotoxins’ risk assessments?” To answer the research question, the concept of data quality for marine biotoxins data destined for risk assessments was dissected into seven individual subtopics on which the perceptions of expert participants of all three roles were captured. The subtopics explored included: data quality challenges; changes in marine biotoxins data quality during the last decade; awareness on data quality legislation and standardization; importance of data quality dimensions, objectives and key performance indicators; importance of data quality-related feedback exchange between stakeholders of the relevant information chain; factors for successful adoption of harmonized standardized formats for marine biotoxins data collection; and suggestions for data quality improvement. The perceptions gathered per subtopic were analyzed using inductive thematic analysis, yielding a total of twelve themes, namely communication, compound, data/quality control, Information Technology or Data Collection Framework, legislation, method, organization, people, policy, risk assessment procedure, society/environment and toxicological aspects, with each subtopic containing items categorized within several of these themes. Certain differences were observed in the perceptions between participants of diverse data roles, in the sense that data producers and to a lesser extent data users mostly focused on themes relevant to analytical methodology, compound particularities, data and quality control, toxicological aspects and policies. On the other hand, data collectors’ views were more concentrated on items relevant to Information Technology or Data Collection Framework and organization. It is noted, however, that interpretation of these trends needs to consider that in many of the study participants different roles overlapped in the same person. This indicates that results should be cautiously generalized. Nevertheless, they could constitute a basis for further research to generate deeper knowledge in the field of data quality in risk assessments relevant to marine biotoxins and gain further insights on the differences in perceptions among data roles.