J.W.J. Burgers

Towards style-based dating of historical documents

Estimating the date of undated medieval manuscripts by evaluating the script they contain, using document image analysis, is helpful for scholars of various disciplines studying the Middle Ages. However, there are, as yet, no systems to automatically and effectively infer the age of historical scripts using machine learning methods. To build a system to date medieval documents is a challenging problem in several aspects: (1) As yet, no suitable reference dataset of medieval handwriting exists, (2) relatively little is known about the evolution of writing styles in the Middle Ages, and especially in the later Middle Ages. Our Medieval Paleographic Scale (MPS) project aims at solving these problems. We have collected a corpus of charters from the Medieval Dutch language area, dating from the period 1300 to 1550. A global and local regression method is proposed for learning and estimating the year in which these documents were written, using several features which have been successfully used in writer identification. The proposed system can serve as a basic tool for the medievalist or paleographer. The experimental results of the proposed method demonstrate its effectiveness.

Image-based historical manuscript dating using contour and stroke fragments

Historical manuscript dating has always been an important challenge for historians but since countless manuscripts have become digitally available recently, the pattern recognition community has started addressing the dating problem as well. In this paper, we present a family of local contour fragments (kCF) and stroke fragments (kSF) features and study their application to historical document dating. kCF are formed by a number of k primary contour fragments segmented from the connected component contours of handwritten texts and kSF are formed by a segment of length k of a stroke fragment graph. The kCF and kSF are described by scale and rotation invariant descriptors and encoded into trained codebooks inspired by classical bag of words model. We evaluate our methods on the Medieval Paleographical Scale (MPS) data set and perform dating by writer identification and classification. As far as dating by writer identification is concerned, we arrive at the conclusion that features which perform well for writer identification are not necessarily suitable for historical document dating. Experimental results of dating by classification demonstrate that a combination of kCF and kSF achieves optimal results, with a mean absolute error of 14.9years when excluding writer duplicates in training and 7.9years when including writer duplicates in training. HighlightsA new image-based historical manuscript dating problem is proposed.We present a family of local contour fragments and stroke fragments features.Historical manuscript dating is performed by writer identification and classification.

Historical Document Dating Using Unsupervised Attribute Learning

The date of historical documents is an important metadata for scholars using them, as they need to know the historical context of the documents. This paper presents a novel attribute representation for medieval documents to automatically estimate the date information, which are the years they had been written. Non-semantic attributes are discovered in the low-level feature space using an unsupervised attribute learning method. A negative data set is involved in the attribute learning to make sure that our system rejects the documents which are not from the Middle Ages nor from the same archives. Experimental results on the basis of the Medieval Paleographic Scale (MPS) data set demonstrate that the proposed method achieves the state-of-the-art result.

A Multiple-Label Guided Clustering Algorithm for Historical Document Dating and Localization

It is of essential importance for historians to know the date and place of origin of the documents they study. It would be a huge advancement for historical scholars if it would be possible to automatically estimate the geographical and temporal provenance of a handwritten document by inferring them from the handwriting style of such a document. We propose a multiple-label guided clustering algorithm to discover the correlations between the concrete low-level visual elements in historical documents and abstract labels, such as date and location. First, a novel descriptor, called histogram of orientations of handwritten strokes, is proposed to extract and describe the visual elements, which is built on a scale-invariant polar-feature space. In addition, the multi-label self-organizing map (MLSOM) is proposed to discover the correlations between the low-level visual elements and their labels in a single framework. Our proposed MLSOM can be used to predict the labels directly. Moreover, the MLSOM can also be considered as a pre-structured clustering method to build a codebook, which contains more discriminative information on date and geography. The experimental results on the medieval paleographic scale data set demonstrate that our method achieves state-of-the-art results.

Historical manuscript dating based on temporal pattern codebook

The Image-based historical document dating problem is studied.We use the informative and meaningful junction patterns to represent handwriting styles.A temporal pattern codebook is obtained to discover the evolution of handwritten patterns over time. Manuscript dating is an essential part of historical scholarship. This paper proposes a framework for image-based historical manuscript dating based on handwritten pattern analysis in scanned historical manuscript images. We first use a singular structural feature to extract the mid-level handwritten patterns in historical document images and then encode the discovered handwritten patterns based on a codebook which contains the temporal information. We evaluate our method on the Medieval Paleographic Scale (MPS) data set and experimental results demonstrate that the feature representation based on the codebook which contains temporal information is more discriminative and powerful for dating. In addition, our proposed method can also visualize the evolution of handwritten patterns over time.

Discovering Visual Element Evolutions for Historical Document Dating

Discovering visual elements correlated with temporal information in images is a challenging problem. In this paper, we study this problem with regard to handwritten historical document dating. We propose a novel stroke descriptor based on a scale-invariant log-polar space using the stroke width as the scale factor. Furthermore, the primary stroke shapes in documents are generated and termed stroke shape elements (also called visual elements in this paper). To discover the changes in visual elements over time, the Evolutionary Self-Organizing Map (ESOM) is proposed with a new time dimension based on the standard Kohonens map to preserve the time topology. The proposed ESOM is a weakly-supervised learning method, integrating the visual elements mining and the evolution learning into one framework to preserve the date topology and time topology simultaneously. The dating of historical documents is performed by voting stroke shape elements based on their labels estimated from the the trained ESOM codebook to the label space, yielding a probability distribution. Experimental results demonstrate the effectiveness of the proposed approach for historical document dating.

The lute in the Dutch golden age : musical culture in the Netherlands 1580-1670

The lutes cultural impact throughout the Dutch Golden Age can be compared to that of the piano in the 19th century. It was the universal instrument for solo music-making, as well as in ensembles and to accompany singers, mainly associated with the social elite - the aristocracy and the prosperous burghers. This richly illustrated book is the first to showcase famous and obscure lutenists, professional musicians and amateurs, the lute music in books and manuscripts, the lute makers and the international lute trade, while also exploring the place of the instrument in the Dutch literature and art of the period.

Representation and governance in the Netherlands, 1250-1983 : Materials for a comprehensive history of politics

SUMMARY Traditionally political history tells the factual story of those who are in power and of those who want to be, often accompanied by studies of the formal expressions of power in the state and its institutions. During the past two decades this ‘old’ history of politics has been renewed and enriched by research from the perspective of political culture. Both in the Netherlands and abroad pioneering studies of political practices, concepts and styles of leadership have resulted from this new approach. In the next few years this cultural angle in the history of politics will be intensified, for instance in research of the understanding and institutionalization of democracy. The recently established research programme ‘Representation and Governance in the Netherlands’ (RGN) at the Institute of Netherlands History wants to take on board this ‘new’ type of political history as well as the ‘old’ variety in order to facilitate both the efforts of those scholars who want to explain cultural traditions and inherited appreciations in the day-to-day routines of politics as well as the work of historians who want to intensify the study of the formation and reach of the state. The RGN project ventures far back through the ages to explore the historicity of political institutions and bureaucratic procedures by opening up materials for analysing both the culture of governance and the practices of politics. In projects that link up the Middle Ages with the twentieth century, from the administrative organization of the counties of Holland and Zeeland during the Hainault period up to and including the establishment and reform of the constitutional state, sources will be recorded and made accessible. The interaction between society and government, often personified by intermediaries such as office-holders, civil servants, journalists, political advisers and the like, will become visible in the many documents to be edited. Upon their publication these sources will enable future researchers to study not only the history of the governing bodies, but also the role that subjects or citizens played or wished to play in shaping the state.

Tussen burgerij en adel. De financiële, politieke en maatschappelijke carrière van de Utrechtse patriciër Lambert de Vries (ca. 1250-1316?)

In de toch al turbulente middeleeuwse geschiedenis van de stad Utrecht vormen de jaren rond de overgang van de dertiende naar de veertiende eeuw een wel zeer woelige periode. Dit was de tijd van een aanhoudende strijd, gevoerd tussen de schepenen en de raad, om de politieke hegemonie in de stad. Deze strijd, waarin twee facties binnen het stadspatriciaat waren verwikkeld, en waarin ook de Utrechtse bisschoppen en de Hollandse graven waren betrokken, escaleerde tot een bloedige burgeroorlog, waaruit de ambachtsgilden in 1304 tenslotte als lachende derde tevoorschijn kwamen. Zo althans wordt deze periode beschreven in de literatuur. In dezelfde literatuur wordt herhaaldelijk, zij het steeds vrij terloops, melding gemaakt van de Utrechtse geldschieter Lambert de Vries, die tijdens het verloop van deze gebeurtenissen een prominente rol heeft gespeeld: hij was de aanvoerder van de schepenpartij, naar hem ook wel de partij van de Fresingen genoemd. Daarnaast is enige aandacht besteed aan zijn relatie met graaf Floris V van Holland: Lambert zou de ambitieuze internationale politiek van deze vorst hebben gefinancierd door het verstrekken van grote leningen. Aan deze man, in zijn tijd blijkbaar een persoon van groot economisch en politiek gewicht, is niet eerder een aparte studie gewijd, en het volgende wil in deze leemte voorzien. Daarbij zal blijken dat enerzijds de in de literatuur over hem geventileerde noties wat betreft zijn politieke en financiele rol slechts gedeeltelijk kloppen, anderzijds dat deze man een opmerkelijke sociale carriere heeft gekend, welke loopbaan meer licht werpt op het maatschappelijk leven van die dagen. Daarnaast zal duidelijk worden dat het zojuist geschetste beeld van de Utrechtse burgeroorlog enige niet onbelangrijke correcties behoeft.

The Library of Johan van Hogelande1

After the death of Johan van Hogelande (c. 1515-78), late Dean and Treasurer of the Chapter of St. Marys at Utrecht and Councillor at the Court of Law in that city, a list of his books was drawn up which is published here. This catalogue leads to the conclusion that he was a cultivated man with a preference for humanist literature; he owned contemporary literature as well as editions of the classics, with a pronounced emphasis on historical works. His library contains furthermore a large collection of lawbooks and a collection of theological works; the latter reveal him as a humanistic and devout Catholic.