The decision to refine the existing content and to extend the scope of Edition I of the ISO 19152:2012 Land Administration Domain Model (LADM) is a response to requests from the international Land Administration (LA) community. This response has to be formally organised in accordance with ISO guidelines. This begins with gathering feedback from ISO/TC 211 Member States on the need for updated and enhanced capabilities of the LADM. In addition, several proposals have been made to extend the scope of the LADM Edition I. After analysing the feedback received, it was proposed to develop the LADM Edition II as a multi-part standard: Part 1 — Generic conceptual model, Part 2 — Land registration, Part 3 — Marine georegulation, Part 4 — Valuation information, Part 5 — Spatial plan information and Part 6 — Implementation aspects. In other words, Edition I focuses on land tenure, while the design and development of Edition II is based on the inclusion of rights, restrictions and responsibilities (RRRs) concerning marine georegulation, valuation information, spatial plan information as well as LADM implementation. 3D representations are relevant for all parts.

This paper focuses on the design of the new structure of the second edition of the LADM and on the (operational) capabilities of this new edition in relation to the LA issues in Parts (standards addressing a specific part of the scope) and Packages (groups of conceptually close classes), with a particular attention to the requirements and design related decisions taken in the revision process. The parts 1, 2, 4 and 5 are the parts in which the authors are currently involved. Part 1 will be a high-level umbrella standard; Part 2 is largely based on LADM Edition I and focuses on land registration, with an enhanced support on the surveying functionality, including new subclasses of spatial unit, and extended 3D spatial profiles. Part 3 harmonises the description of RRRs and aligns land concepts with marine aspects from the marine domain based on the International Hydrographic Organisation (IHO) S121 Maritime Limits and Boundaries Product Specification. Part 4 deals with valuation information used and produced in the context of land administration, while Part 5 deals with spatial planning information and includes the planned use of the land (zoning), resulting in RRRs. Lastly, Part 6 is planned to be about implementation of the LADM and will be developed in close collaboration with the Open Geospatial Consortium (OGC).

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Evaluating the performance of a land administration system (LAS) is a critical task as it can provide input for improving the operational system. Through such an evaluation, the strengths and weaknesses of the existing system can be identified, and actions can be taken to improve it. Efforts have been made to develop frameworks and best practices for the assessment and comparison of the performance of LASs. Amongst the most prominent are the ‘Land Governance Assessment Framework’ (LGAF) of the World Bank and the ‘Global Land Indicators’ proposed by the Global Land Tool Network (GLTN) and the United Nations Human Settlements Programme (UN-Habitat) in its Global Land Indicators Initiative (GLII). The GLII indicators are closely related to the UN-Sustainable Development Goals (SDGs) indicators on land tenure security, namely SDGs 1.4.2 (%adults with secure tenure rights), 5.a.1 (%agricultural population with secure rights over agricultural land), and 5.a.2 (women's equal rights to land ownership).

The Land Administration Domain Model (LADM), an International Standard (ISO, 2012), can be used to monitor global indicators proposed by various international organizations and to evaluate the performance of LADM-based LASs, as LADM Edition II now provides full support for all land administration (LA) functions including marine georegulation, valuation information and spatial plan information. Interface classes to the LADM are designed to support the generation and management of products and services, such as the monitoring of global performance indicators for LASs.

This paper is a follow-up on Chen et al. (2024), which was focusing on formalizing SDG land related indicator using LADM. The objective of this study is to explore the extent to which LADM can be used to also monitor the indicators of LGAF and GLII. To this end, the indicators are categorized according to their degree of association with LADM (i.e. full computational association, partial computational association, indirect association, association with other standards and non-association), and interface classes are created based on the results. The results show that LADM can be used to monitor a significant portion of the indicators of LGAF and GLII, although most of the indicators are related to a country's national legislation, its implementation and organizational decisions and capability.@en

This study illustrates the linkages between the ISO’s Land Administration Domain Model (LADM) and the UN’s sustainable development goals (SDGs), highlighting the role of the LADM in promoting effective land administration suitable for efficient computation of land/water (space)-related SDG indicators. The main contribution of this study is the formalization of SDG indicators by using the ISO standard LADM. This paper proposes several SDG-indicator-related extensions to the multi-part LADM standard that is currently under revision. These extensions encompass the introduction of new procedures for calculating indicators, the integration of blueprints for external classes to fulfil additional information needs and the design of interface classes for presenting indicator values across specific countries and reporting years. In an innovative approach, this paper introduces the Four-Step Method—a powerful framework designed to formalize SDG indicators within the LADM framework. Detailed attention is devoted to specific indicators, including 1.4.2 (secure land rights), 5.a.1 (women’s agricultural land rights), 14.5.1 (protected marine areas) and 11.5.2 (valuation as a basis for direct economic loss). In short, the Four-Step Method is pivotal in eliminating ambiguities, enhancing the efficiency of indicator computation and securing more accurate indicator values that more truly reflect the progress towards SDG realization. This approach is also expected to work with other (ISO) standards for other SDG indicators.@en

Cadastral surveying involves the delineation of property boundaries and the extent and documentation of easements and restrictions (imposed by private or public law), forming the foundation for Land Administration (LA). Survey models and processes constitute vital parts of Cadastres and Land Administration Systems (LASs). However, these models are often inadequately documented and lack standardization in practice. To address the global diversity and complexity of legal and administrative challenges in LA, standardization efforts have yielded the ISO 19152:2012 (ISO, 2012) Land Administration Domain Model (LADM), the Global Land Tool Network's (GLTN) Social Tenure Domain Model (STDM), and the OGC LandInfra/InfraGML standard. The current edition of the LADM focuses on standardised conceptual modelling of LA-related information, including a dedicated sub-package for Spatial and Surveying representation. As part of the ongoing LADM revision, a refined survey model is being developed to support a broad range of surveying and data acquisition approaches and levels of accuracy. Recognizing that surveying technology is not bound by national practices and regulations, this paper focuses specifically on the surveying aspect of LADM. It illustrates that the proposed refined survey model is applicable not only to conventional real property formation but also to participatory land rights recordation processes. The approach adopted in this research is technology-neutral, accommodating the ongoing evolution of surveying technology. It offers support for a broad range of surveying and data acquisition approaches, with varying levels of accuracy. As the demand for high-precision positioning has been persistent within the land mapping and surveying community, particularly since the initial adoption of GPS, aiming to achieve centimetre-level accuracies (initially confined to local services), the paper addresses the fundamental principles of the High Accuracy Service (HAS) concept within the proposed model. The main results presented in this paper are the conceptual model of the refined survey model of LADM Edition II (ISO19152–2), as well as an abstract, reference, cadastral surveying workflow following the principles of the proposed model.

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This paper examines the requirements based design of the LADM Edition II. The requirements are the starting point for the Abstract Test Suite (ATS, Annex A in an ISO standard). The requirements/ATS can be used to assess if a given LADM country profile with a specific application schema is conformant with the LADM standard. The requirements are a new aspect of ISO standards and this offers several benefits: 1. requirements express explicitly the needs from experts in the domain, 2. requirements are a very concise manner to describe the content of the standard, 3. requirements are used to introduce of the actual standard content (in the case of LADM, part of the UML class diagram), and as mentioned above, 4. requirements form the basis of the ATS. This paper describes the new structure of the second edition of the standard and the capabilities of this new edition, which is organized in multiple Parts (standards addressing a specific part of the scope) and Packages (groups of conceptually closely related classes, i.e. with relative high number of associations between the classes from one package compared to the number of cross package associations), with a particular attention to the requirements and design related decisions taken in the revision process.@en

The timely and effective dissemination of property values is an essential part of a transparent and efficient property valuation system. Over the last decade, web-based data-sharing systems have been increasingly used for the dissemination of assessed property values. 3D valuation units (e.g., condominium) and groups (aggregation of valuation units, e.g., a building floor in a multi-occupied building, a multi-occupied building, street, district or valuation zone) may be required to better communicate with users and to support a more effective and efficient dissemination. However, none of these systems share valuation information associated with 3D representation of the valuation units and groups. In this paper, a prototype of a web-based system is developed utilising the proposed Valuation Information part of the Edition II of the ISO 19152 Land Administration Domain Model compliant dataset for not only disseminating the spatial, physical, thematic and temporal characteristics of 3D valuation units, but also for sharing the valuation statistics at each designated level and with level-specific attributes. It is expected that the outcomes of this work may contribute to the development of local or national valuation systems and systems for geo-based data visualisation for effective and efficient sharing of valuation information. As such, it is anticipated that the study's outcomes will not only increase the level of communication with the public, but also support politicians and planners in their decision-making processes and help them to better analyse and understand the property market. With the proposed system, confidence in valuation results can be further increased due to the high level of transparency.

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In February 2019 the OGC White Paper on Land Administration is published. This White Paper provides an overview of the land administration domain and relevant developments. It also proposes necessary actions for the design and development of an implementation standards. The document includes an overview of needs and requirements as earlier discussed during the various LADM Workshops. During the closing session of the 2021 LADM/3D workshop (embedded in the FIG e-Working Week 2021) FIG expressed its commitment to collaborate with ISO and OGC regarding the implementation of LADM as an integral component of the standardisation efforts in land administration. Currently, the LADM revision is ongoing and includes land registration, marine space geo-regulation, valuation information, spatial plan information. Further, enhanced support in cadastral surveying is proposed to be provided, through a comprehensive survey model. The new edition is multipart, part 6 is on a standard for LADM implementation. The development of this can be strategically aligned with the developments of the other parts of LADM edition II. This paper serves as an initial step towards fostering a dialogue to promote the implementation of LADM. It emphasis the creation of a Land Administration Domain Model Standards Working Group Charter within the OGC. A draft charter is currently available for reference, along with insights from the 2019 White Paper. It is imperative to engage stakeholders from industry/business, government and academia in this development to ensure its success and relevance.@en

This paper refers to the creation or update, organisation and initial analysis of the results from the 4th FIG 3D Land Administration Questionnaire, as an activity of the FIG Working Group 3D Land Administration 2022-2026. The questionnaire on 3D Land Administration is conducted as a successor of the previous questionnaire on 3D Cadastres, which has been conducted three times till today, by the Working Group in 2010, 2014 and 2018. The first, documented the status in 2010 and expectations back then for 2014. This was followed by the second questionnaire (status 2014 and expectations 2018) and the third one (status of 2018 and plans for 2022). All members/ countries the Working Group have been requested to provide information about the current the status of 3D Land Administration Systems/ Cadastres (at the end of 2022) and the expectations/plans for 2026. The purpose of the survey that is has been conducted and reported in this paper, is to make an inventory of the status of 3D Land Administration at the end of 2022 and the plans/ expectations for the near future (2026) from countries all over the world. The completed questionnaires, per country are fully available via the participants’ page of the 3D Land Administration Working Group website. The responses have been analysed and reported in various publications (van Oosterom et al. 2011, van Oosterom et al. 2014 and Shnaidman et al., 2019). In total, thirty-seven (37) countries have completed the questionnaire and have been received by time of conducting the initial analysis as described in this paper. Similar to the previous questionnaires, it is likely that there will be some completed questionnaires that will be sent by the countries later. @en

The first edition of the Land Administration Domain Model (LADM) has been available as a formal International Standard since the 1st of December 2012, published as ISO 19152:2012. It is based on / makes use of a number of standards, in particular those published by ISO/TC 211 and, of course, other committees. In addition, non-ISO standards and international guidelines related to land administration have been used as much as possible in the development of LADM Edition I. The systematic review of LADM Edition I has been officially launched and the process of developing LADM Edition II is now underway. The new edition not only refines the content of LADM Edition I, but also expands the scope to include marine georegulation, valuation information, spatial plan information and implementation. As a result, LADM Edition II is based on more standards, not only because of its expanded scope, but also because of the standards published after LADM Edition I and the principle of reusing existing standards wherever possible. Since the publication of LADM Edition I, it has been widely recognised by the international community and implemented by several countries. It is also applicable to the implementation of relevant parts of international standards, guidelines and frameworks, as well as the Sustainable Development Goals (SDGs). LADM Edition II has somewhat more links to international standards, guidelines and frameworks, as its scope is broader than Edition I. The purpose of this paper is to document which standards LADM Edition II is based on and associated with, which guidelines and frameworks are in some way related to LADM.@en

The interest in using 3D data in property valuation has been increasing during the last decade. The usage of 3D data models in valuation can be basically grouped in two main categories: (a) supporting mathematical models with variables produced through 3D analyses (e.g. view) in order to better estimate the values of properties and (b) consuming 3D data models to visualise valuation units in 3D and disseminate values of properties associated with the visualised units (legal or physical space). The current paper focuses on the latter category in particular. The main purpose of this paper is to develop a prototype system utilising the proposed Valuation Information Model extension of ISO 19152 Land Administration Domain Model (LADM_VM) compliant dataset in order to create web-based, thematic valuation maps for 3D valuation units (e.g. condominium) and groups (e.g. multi-occupied building). In the first part of the paper, it is attempted to justify why an extension to the core LADM is required to represent valuation information. It is noted that LADM_VM enables to record 3D spaces of valuation units, and input and output data of 3D analyses. Therefore, LADM_VM can be used as basis for developing 3D visualisation and dissemination prototype. In the second part of the paper, special attention will be given to the 3D visualisation and dissemination of spatial, thematic and temporal characteristics of valuation information and a prototype is developed using the open datasets of the Netherlands. It is expected that the outputs of this paper will contribute to the development of local or national prototype systems for sharing valuation information effectively and efficiently. Therefore, it may be considered that the outputs of the paper not supports in increasing the communication level with public, but also supports politicians and planners in decision-making processes and helping them to understand the property market better. With the proposed system (prototype) the trust in the valuation is expected to further increase due to the high level of transparency. @en

Among the topics that are introduced and/ or being refined in the context of the revision of the LADM 19152:2012, the legal Land Administration-related aspects are being investigated. With the knowledge and the experience from the developments of the LADM so far, and the ongoing discussion between the parties involved in the standardisation process, the need to clarify certain legal land-related aspects and to examine the alternatives for further refinement is highlighted. Therefore, this paper presents prior work on LADM-related legal aspects since the vote of LADM as ISO standard (2012), till the time of the preparation of this paper (2021) to report the necessary background for this research. This concerns the developments related to the various legal refinements that have been proposed during this time period and specifically the refinement of the legal profiles, the LADM functional support to representation of both statutory and customary tenure and the work regarding the explicit definition of restrictions that arise from Public Law. Moreover, this paper focuses on documenting the proposals on a refined legal model for the LADM Edition II. These include the following: (a) more detailed classification of RRRs, based on the two major types of interests in land: privately agreed interests as well as regulations imposed by a public agency and Public Law restrictions. The paper also includes (b) a discussion on the extent that LADM Edition I provides efficient support for the title and deed registration systems (as others e.g. in socialist environment), as well as (c) a discussion on how restrictions and responsibilities can be modelled as rights’ relationships between an owning and a benefitting Party. @en

The ISO 19152:2012 Land Administration Domain Model (LADM), focuses on standardised modelling of land information at the conceptual level, and together with LADM’s three main packages, it has a dedicated sub package for Spatial and Surveying representation. The first edition of the standard provides multiple spatial representations, and a rather generic survey model based on the ISO 19156:2011 Observations and Measurement Standard (O&M). As an ISO standard, the LADM is subject to periodic revision, and currently, its revision is ongoing and among other refinements, the enhanced support of the surveying model, both at conceptual and implementation level is expected. In this scene, in order for LADM to support a broad range in surveying and data acquisition approaches and accuracies, a refinement is ongoing considering the recent evolution of technology and the encodings used in practice. Therefore, a refined survey model has been prepared and is included at the New Working Item Proposal for LADM Edition II – Part 2, with various data acquisition techniques, as presented in this paper. Based on it and on the experience and requirements from the industry and the standardization organisations, this paper presents the requirements that encoding formats should fulfill to support the revised surveying model. @en

A code list in Unified Modeling Language (UML), a simple list of values without any structure, can be employed as a simple data type to further capture the semantics of a domain. The code list values as used in international standards (e.g. ISO and OGC) are generally presented without definition, reference to the source of a definition, multi-lingual alternative term support and semantic relationships (e.g. hierarchical, associative). Moreover, managing, implementing, and maintaining UML code lists can be considered as a difficult task since they generally do not provide structured and semantically enriched values. This is also true in the case of ISO 19152:2012 Land Administration Domain Model (LADM), which is currently under systematic review and adding more content, meaning and structure to code list values could be considered an improvement. In last decade, there is a growing interest in representing terms as well as code list values using Semantic Web technologies (e.g. RDF, OWL, SKOS, SPARQL) and making them available on a registry (e.g. ISO/TC211 Geolexica, OGC Definitions Server, INSPIRE code list register, BARTOC), including land administration domain (e.g. CaLAThe, LandVoc). However, there is no joint understanding in structuring, extending and maintaining code list values, which may be achieved through an agreed metamodel. Such a metamodel should also provide insight into content, localisation (multi-lingual support), versioning and implementation. The aim of this study is to propose a framework (basically a metamodel) for structuring, extending, maintaining and implementing semantically enriched code lists, and to discuss the application of the proposed framework to be included in the revision of LADM. To achieve this aim, the requirements for refined code list values are firstly collected considering existing thesauri, vocabularies and standards. Subsequently, a metamodel is proposed for the refined code list. The proposed metamodel is applied to a code list of LADM as well as a part of a selected country profile.@en

Land and space are major driving factors in doing business in urban areas. Cities around the world are performing land management techniques to achieve sustainable urban development. The World Bank acknowledges the importance of land management practices and promotes it as the Ease Of Doing Business (EODB) indicators for a supportive environment for economic activities. In improving a city's competitiveness, local governments need to establish a reliable Land Administration System to organize unrenewable urban land and spaces and simultaneously reduce information asymmetry between actors. A modernized LAS is needed to accommodate the four functions of land management: land tenure, land value, land-use planning, and land development. The ISO 19152:2012 on Land Administration Domain Model (LADM) standard offers a foundation to establish information interoperability in land management that is crucial in modeling the relationship between people and land (and space), the geometrical components, as well as documented Rights, Responsibilities, and Restrictions (RRRs) in land. To promote the exchange of information between the domains of land administration domain and spatial planning, an extension of LADM, the Spatial Plan Information Package (SP Package), was proposed to support cities organizing information in land management. This article presents the proposed spatial plan information extension to the LADM country profile for Indonesia. This work also develops a proof-of-concept of the package in the two biggest Indonesian cities (Jakarta and Bandung) with adaptation to the current national data management policies. Our research shows positive results on making the LADM country profile reflect on the real condition and improving LAS's adaptability to be integrated with the Spatial Information Infrastructure.

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The origin of surveying has a close connection with the designation of land boundaries, while cadastral surveying is a means of defining the limits of properties, thus forming the basis for land administration, serving as an important tool to gather, assess, and update geographical spatial data. Accurate description and record of land are the fundamentals to their rational use and conservation and form the core of wellestablished Land Admini stration Systems (LASs). Although surveying models and approaches are important for Cadastres and LASs, they are not always documented in detail, while with the rapid advances in technology and geoinformation they need to be revised quite often. The ISO 1 9152:2012 Land Administration Domain Model (LADM), which focuses on standardised modelling of information at the conceptual level, has a dedicated sub package for Spatial and Surveying representation. The first edition of the standard provides multiple spa tial representations, and the ongoing LADM revision shall support a broad range in surveying and data acquisition approaches and accuracies, considering the evolution of technology and the encodings used in practice. A conceptual model of the refined surve y model is expected to be included in Part 2 of the new edition of the standard, while its technical implementation(s) covering both 2D and 3D boundaries in Part 6. This paper aims to present the fundamentals of the refined Survey Model of LADM Edition I considering the need to support the interconnection with the everI, evolving surveying methods and acquisition techniques in a standardised way, including among others the Galileo High Accuracy Services requirements and the alignment with other standards, as well as participatory methods. One of the standards which synergy with LADM is investigated in this paper is the OGC LandInfra, and specifically Part 6 “Survey”, that provides a framework for information about observations, processes and their results collected during survey. The development of the proposed model was informed by two case studies using survey plans according to Danish practice and cadastral data from the Hellenic Cadastre.@en

A new edition of the Land Administration Domain Model (LADM) is under further development in ISO/TC 211 on Geographic Information. The Committee is developing this new edition of the LADM – as multipart – working titles are as follows: Part 1 – Fundamentals Part 2 – Land Registration Part 3 – Marine Space Georegulation Part 4 – Valuation Information Part 5 – Spatial Plan Information Part 6 – Implementations The decision to publish LADM Edition II as multipart had as a consequence that a New Work Item Proposal (NWIP) and a Working Draft (WD) have to be formulated for each Part. In 2020, the NWIP/WD have been submitted to ISO/TC 211 for Part 1 by Standards Australia (SA) with input from the author team on behalf of the FIG. The result of the voting was positive. Comments have been submitted, which will be processed and used in the next stage of the standard: the Committee Draft. It is planned that FIG will submit the NWIP for Part 2 before summer 2021. And it is expected that the same will happen this year for Parts 4 and 5. Those submissions are expected to be in close cooperation with other international professional organisations (i.e. IHO, RICS, OGC, etc.).@en

The growing recognition and influence of the ISO 19152:2012 Land Administration Domain Model (LADM), is revealed by the multiple country profiles that have been developed based on the standard in various jurisdictions across the world. The ongoing revision of the LADM Edition I, initiates discussions related to the development of country profiles, as well as considerations regarding their maintenance. Till today, various approaches for creating LADM-based country profiles have been followed. This resulted in the creation of an interesting mosaic of country profiles’ developing methods, with parts to be exploited and an outline of the basic steps of the development provided. Based on this knowledge, the aim of this paper is to design a methodology for the development of LADM country profiles, expected to become part of future version of the ISO 19152 LADM, the Edition II. Collective experience from good practices in the development of profiles based on LADM Edition I reported in the literature have been reviewed and used as basis for a qualitative comparative analysis. For this purpose, a set of six characteristics/criteria was developed based on key publications selected through experts’ consultation. The characteristics are generic and can be applied to all the country profiles, as well as they refer to the lifecycle of the development and implementation of a country profile, taking into account legal, institutional and technical issues. Characteristics regarding the scope of country profiles are also considered. Given this context, the design of the methodology to develop LADM-based country profiles is presented, structured in three phases: scope definition, profile creation and profile testing.

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The timely and effective dissemination of property values is an essential part of a transparent and efficient property valuation system as property values are required in several land administration processes, such as land acquisition, taxation, transaction, consolidation, readjustment and transformation. In the last decade, a web-based data-sharing system has been increasingly used for dissemination of property values. The 3D visualization of valuation units may be required in order to better communicate with users and provide more effective and efficient dissemination, however, none of those systems share valuation information associated with 3D representation (legal or physical) of property (valuation) units. The objective of this paper is to reveal the requirements, opportunities and challenges for web-based 3D visualization and dissemination of property valuation information. To deliver this objective, the requirements for U(ser), D(ata), and V(isualization) are investigated. The general public/property owners and professionals are determined as main user groups in this research. For each of the groups specific data and 3D visualization requirements are discussed and a number of suggestions are provided for developing an effective dissemination of property valuation information. These requirements includes the visualization of multi-part properties (e.g. condominium unit, storage unit, car parking), thematic mapping of valuation information, and aggregation of valuation units into valuation units groups. Furthermore, the capabilities of the LADM Valuation Information Model as a schema for storage, and the features and functionalities of 3D visualization platforms (geoweb viewers) in terms of better value dissemination (e.g. altering visual variables, solution for occlusion, visualizing below surface properties) are briefly investigated. Lastly, an initial prototype is developed and presented.@en

Spatial data in a Land Administration (LA) establish a fundamental geospatial data theme (see UN GGIM, 2018) and the integrated geospatial information framework for any Spatial Data Infrastructure (SDI). Domain-specific standards, an integral component of the SDI, play an essential role to represent the semantics of domains, specify links between distributed registries and databases, and stimulate the development and implementation for Land Administration Systems (LAS). As an international descriptive standard providing an abstract conceptual schema, the ISO 19152:2012 Land Administration Domain Model (LADM) has been used and is being used as a reference for the implementation of LAS. Various approaches have been used for the LADM implementation that includes elaborating (via a country profile) and realizing a technical model suitable for the implementation (van Oosterom and Lemmen, 2015). LADM focuses on a specific function of LA that is interested in Rights, Responsibilities and Restrictions (RRR) affecting land, and the geometrical components thereof. The land value function of LA is considered outside the scope in the first edition. Recently, for extending the flexible and modular basis of the LADM, a valuation information model is developed for the specification of valuation information maintained by public authorities. It identifies the links between property valuation and the other LA registries and databases (e.g., cadastre, land registry, building and dwelling registries) that may enable interoperability across systems. The conceptual schema of the model provides a common basis to direct the development of local and national valuation databases and information technology products and services, following an approach similar to the LADM implementation. The proposed LADM Valuation Information Model is on the agenda of the development of the second edition of LADM within ISO/TC211. The operability of the newly proposed conceptual model needs to be evaluated through technical implementation. This paper describes the development of a prototype for the implementation of the LADM Valuation Information Model and assesses its operability through a case study for Turkey. The primary aim of the paper is to test the capabilities of the LADM Valuation Information Model using the required and produced data in recurrent valuation processes, but not to build a specific information management system for Turkey. As the implementation of a LADM compliant prototype initially requires the development of a country profile at conceptual level, methodologies applied for LADM profile development are examined and then a Turkish LADM Valuation Information Model country profile is proposed using the Conceptual Schema Languages (CSL) of the Unified Modelling Language (UML) and INTERLIS. INTERLIS is a formal language as well as a set of software tools that support LADM implementations. Subsequently, approaches and tools used in the LADM implementation are investigated and utilized for the automated transformations from the country profile to several technical models. In this context, the article presents the experiences gained during the implementations. Moreover, strategies for implementing and managing property valuation information more efficiently (e.g. bi-temporal aspects of valuation information management) are also studied and applied to the implementation. The generated technical models are then populated with sample datasets related to recurrent property valuation including the geometries of valuation units, as well as valuation information covering several years. The developed prototype is then tested through a number of queries to assess whether the LADM Valuation Information Model fulfils information management needs of recurrent valuations. The main contribution of this paper is to provide a holistic approach on how to develop an LADM conformant prototype for managing property valuation information.

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