How demanding is the revealed preference approach to demand

A well known problem with revealed preference methods is that when data are found to satisfy their restrictions it is hard to know whether this should be viewed as a triumph for economic theory, or a warning that these conditions are so undemanding that almost anything goes. This paper allows researchers to make this distinction. Our approach builds on theoretical support in the form of an axiomatic cardinal characterisation of a measure of predictive success due to Selten(1991). We illustrate the idea using a large, nationally representative panel survey of Spanish consumers with broad commodity coverage. The results show that this approach to revealed preference methods can lead us radically to reassess our view of the empirical performance of economic theory.

Silvius Leopold Weiss and the Improvised Prelude

The prelude, whether pre-composed or improvised, presented an opportunity for lute players of all periods to demonstrate their skill in improvisation and exploit their powers of musical expression in a very personal way. The preludes and fantasias of Silvius Leopold Weiss (1687-1750) demonstrate a masterful continuation of the same tradition. This article aims to show that some pre- ludes in lute manuscripts from the middle of the eighteenth century contain features that are related with attempts to emulate Weiss’s powers of improvisation. Unmeasured preludes for lute survive in larger numbers than the well-known French repertory for the harpsichord. Some are based—at least in their openings—on standard gestures; in particular, a common d-minor melodic formula can be found in at least twenty-five examples from the 1650s through to Weiss’s early years of maturity. Otherwise, a basic harmonic sequence provided a flexible structure for preludes as shown in sketches or more complete examples in many sources. After a brief discussion of some prominent features of improvised music, the article focusses on a group of manuscripts from Silesia showing that some passages within written-out preludes in these sources are extracts from other works, including by Weiss himself, suggesting that quotation may have been a step on the way to learning to compose

After the search is over... the work begins

A narrative and discursive discussion of some adventures in musicology using a simple MIR system

The Segment Ontology: Bridging Music-generic and Domain-specific

Existing semantic representations of music analysis encapsulate narrow sub-domain concepts and are frequently scoped by the context of a particular MIR task. Segmentation is a crucial abstraction in the investigation of phenomena which unfold over time; we present a Segment Ontology as the backbone of an approach that models properties from the musicological domain independently from MIR implementations and their signal processing foundations, whilst maintaining an accurate and complete description of the relationships that link them. This framework provides two principal advantages which are explored through several examples: a layered separation of concerns that aligns the model with the needs of the users and systems that consume and produce the data; and the ability to link multiple analyses of differing types through transforms to and from the Segment axis

06171 Abstracts Collection -- Content-Based Retrieval

From 23.04.06 to 28.04.06, the Dagstuhl Seminar 06171 `Content-Based Retrieval\u27\u27 was held in the International Conference and Research Center (IBFI), Schloss Dagstuhl. During the seminar, several participants presented their current research, and ongoing work and open problems were discussed. Abstracts of the presentations given during the seminar as well as abstracts of seminar results and ideas are put together in this paper. The first section describes the seminar topics and goals in general. Links to extended abstracts or full papers are provided, if available

Searching Page-Images of Early Music Scanned with OMR: A Scalable Solution Using Minimal Absent Words

We define three retrieval tasks requiring efficient search of the musical content of a collection of ~32k page images of 16th-century music to find: duplicates; pages with the same musical content; pages of related music. The images are subjected to Optical Music Recognition (OMR), introducing inevitable errors. We encode pages as strings of diatonic pitch intervals, ignoring rests, to reduce the effect of such errors. We extract indices comprising lists of two kinds of ‘word’. Approximate matching is done by counting the number of common words between a query page and those in the collection. The two word-types are (a) normal ngrams and (b) minimal absent words (MAWs). The latter have three important properties for our purpose: they can be built and searched in linear time, the number of MAWs generated tends to be smaller, and they preserve the structure and order of the text, obviating the need for expensive sorting operations. We show that retrieval performance of MAWs is comparable with ngrams, but with a marked speed improvement. We also show the effect of word length on retrieval. Our results suggest that an index of MAWs of mixed length provides a good method for these tasks which is scalable to larger collections

ECOLM and Lute Tablature

ECOLM or “Electronic Corpus of Lute Music” (1999-2002) was a project led by Tim Crawford at King’s College London which developed and populated a database of lute tablature encodings with metadata, for scholarly use, queried using a web interface. Subsequent projects ECOLM II (2002-2006) and ECOLM III (2012) expanded the database and used it for some computational musicological investigations. The resulting database was hosted on a public-facing web server at Goldsmiths, University of London. It is still running today, although nobody is formally responsible for maintaining it. We consider the status of ECOLM and a number of related lute tablature resources, discuss their audience and challenges for sustainability, and identify three alternative directions for sustainable development

End-to-end loading of new music libraries to F-Tempo via IIIF

This poster shows the completion of the work that we presented in last year’s IAML-DLfM joint session. F-Tempo provides an online interface to search full-page scores of renaissance and early baroque music scores. During initial development, F-Tempo consisted of only one database of scores, manually curated and added to the search index. Subsequently, further databases were manually curated and integrated to the index. Any new content needed to be manually curated and added to the application, a process which involved image manipulation, manually executing processes to transform data, and the manual editing of the website source code. We have finished our work to make the F-Tempo database extensible by automatically importing the contents of a music library based on IIIF manifests provided by libraries. Our initial proof of concept imports data from the Music collection of the British Library. Because the IIIF manifest does not include structured metadata for documents, we additionally developed individual data lookup methods for each library that we wished to import. For example, for the British Library we are able to obtain the MARC record for a book and obtain other metadata including a description of the work, the composer (linked to a VIAF record where possible), and the RISM identifier if it exists. An automatic pipeline can take a list of URLs of IIIF manifests and download the manifest and any associated metadata, download each image in the manifest, identify which images contain music, perform OMR on those pages, perform the MAWs computation used for the search process used in F-Tempo (Crawford 2018), and add all of the metadata for the IIIF document to our search index. Scores in symbolic formats can also be imported to the F-Tempo index. We have imported 19,000 scores of music in MusicXML format from the Choral Public Domain Library (CPDL). This process also obtains metadata of the scores, but does not include images. The search interface of F-tempo previously allowed for the search of music by choosing an existing page from the database, or uploading a previously unseen page of music. This interface has been extended to take advantage of the metadata collected by each library lookup. It is now possible to navigate content by Library, Book, Composer (even if their works are in different libraries), shelf numbers, or RISM identifiers. Metadata that is present in the IIIF manifest is indexed, and a free-form search box allows for users to identify works by performing a search. Search results that match images from libraries are presented as images. Search results that match symbolic scores are rendered using the Verovio engraving library

Exploring early vocal music and its lute arrangements: Using F-TEMPO as a musicological tool

In its earliest state, F-TEMPO (Full-Text searching of Early Music Prints Online) enabled searching in the musical content of about 30,000 page-images of early printed music from the British Library's Early Music Online collection (GB-Lbl). The images were processed using the Optical Music Recognition (OMR) program, Aruspix, whose output is saved in the MEI (Music Encoding Initiative) format. To enable fast searches of the MEI, we adopted an indexing strategy that is both scalable and substantially robust to the inevitable errors in the process. In this paper we show how searches using these indexes may be used as a first step in two useful musicological tasks without exhaustively processing the full encodings. The F-TEMPO resource has subsequently been augmented to about 500,000 images including a large number from the Bavarian State Library in Munich (D-Mbs), and other libraries (D-Bsb, PL-Wn and F-Pn). Most recently, a new and more robust system architecture is in development, together with a new interface conforming better to modern web standards. The simple, yet robust, indexing method we use can be applied to scores encoded in any format from which strings of pitches each corresponding to a voice or instrument in the score can be derived. In addition to page-images, in its current form F-TEMPO now includes a collection of over 10,000 scores encoded in MusicXML, largely of early music, from the online Choral Public Domain Library (CPDL). To show the potential for F-TEMPO as a tool for musicologists to explore the full-text content of the collections, we look at two simple tasks: (a) finding pages which contain similar music to a given query page; and (b), given a query representing an approximation to the highest-sounding voice from a lute arrangement of a popular vocal item from the 16th century, finding a likely vocal model within the F-TEMPO index