Mecanismos de atención de quejas, reclamos de la comunidad y resolución de conflicto

A different approach to understanding image subject content derives from the discipline of art history and the formal analysis of Renaissance art works outlined in a seminal paper by Erwin Panofsky (1955).

Panofsky distinguishes three levels of subject matter or meaning: pre-iconographical description, iconographical analysis, and iconology. Pre-iconographical description relates to everyday objects and events and requires no specialist knowledge. Iconographical analysis deals with images, stories and allegories for which knowledge of specific themes or concepts is needed. Iconology requires interpretation of the “intrinsic meaning or content” and an insight into symbolical values and their varying use over time.

Shatford (1984; 1986; 1994) modifies Panofsky's approach to provide LIS with a theoretical basis for describing an image and classifying its subject matter (Table 2.1). Shatford bases three different subject levels on Panofsky’s theory: the “specific

of”, the “generic of” and the “about”. She extends these by four facets: “who?” (objects and beings), “what?” (activities, events and emotions), “where?” (place) and “when?” (time). The resulting classification scheme provides an indexer with a structure for systematically identifying possible subjects.

Table 2.1 – Shatford/Panofsky subject classification matrix

Iconography (S=Specifics) Pre-Iconography (G=Generics) Iconology (A=Abstracts) Who? Individually named person,

group, thing (S1) Kind of person or thing (G1)

Mythical or fictitious being

(A1) What? Individually named event,

action (S2) Kind of event, action, condition (G2) Emotion or abstraction (A2) Where? Individually named

geographical location (S3) Kind of place: geographical, architectural (G3) Place symbolised (A3) When? Linear time: date or period

(S4)

Cyclical time: season, time of

day (G4) Emotion, abstraction symbolised by time (A4)

As a minimum, Shatford proposes indexing images with subjects for “ofness”, that is both the generic “of” (e.g. bridge; suspension bridge) and the specific “of” (e.g. Brooklyn Bridge). She suggests there are thresholds where indexing should cease, even if not constrained by resources. One is the threshold of detail, so no element which is an integral part of the whole should be named. For example, if a picture shows a woman, “woman” would be indexed but not the parts of her body. Another is the threshold of pertinence, so only meaningful and identifiable objects should be indexed. She also notes that while the aboutness of an image represents a subjective analysis of the image, subjectivity affects almost every aspect of picture indexing. Critics question the practical ability to distinguish clearly between objective and subjective of and about aspects. Krause (1988) equates these respectively to “hard” indexing, concerned with description, and “soft” indexing, relating to meaning and personal reaction, but admits the distinction is difficult to maintain. Svenonius (1994) is sceptical concerning aboutness because of the difficulty in expressing the visual in words. Aboutness, or iconographic indexing, is further criticised for requiring more expertise and decision making than the other levels and for potentially obscuring or eliminating useful information or resulting in wrong interpretations (Leung et al., 1992). One response to these difficulties is advocacy for indexing to focus on primary or pre-iconographic subject matter as both simpler to

index and more accessible to the general user (Markey cited in Hogan et al., 1991; Keister, 1994). This overlooks the subjectivity in selecting what primary subjects are indexed.

More fundamentally, Panofsky’s and Shatford’s models are criticised for inadequately providing qualitative content and requiring specialist knowledge in searching (Burford et al., 2003). Critically, neither adequately addresses the question of "meaning for whom?" (Burke, 2001, p. 41).

Jorgensen (1995; 1998), inspired by a need to consider a broader range of attributes, investigated user descriptions. She identifies twelve classes and forty-seven image attributes grouped into three levels: perceptual, interpretative, and reactive (or affective). She proposes indexing, as a minimum, four classes: objects, people, colour and location. She suggests that as “Content/Story” and other abstract and affective attributes are typically described, that indexing might benefit from more subjective interpretations. Jorgensen (1996) trialled an indexing template describing the twelve categories with “naïve” users sorting items into the appropriate classes. The trial was not very successful, possibly because her class organisation is not systematic in relation to how users extract meaning (Burford et al., 2003, p. 130). Furthermore, her classes relating to subjects lack the clearer and more developed structure proposed by Shatford/Panofsky.13

Concurrently, Hastings (1994) studied eight art historians' interactions with a small database of digitised art images. She proposes a pyramid model with three faces: queries, access points, and computer manipulations. The model arranges queries in four levels: identification of “who?”, “where?” and “when?”; of type “what are?”; of style, subject and “how?”; and for meaning, subject and “why?”. These query levels are combined with proposed access points in an information retrieval system. Hastings’ model has received less attention than it deserves. This undoubtedly is because her research was with art historians and coincided with Jorgensen’s more influential work with a more general group of users, and because her subject level framework is less developed than that of Shatford/Panofsky.

Jaimes and Chang (2000) have developed a conceptual indexing structure for visual and non-visual content. The indexing structure is useful for bringing together the syntactic, or perceptual, and the semantic, or conceptual, elements and relationships. The “semantics” comprise generic objects and scene, specific objects and scene, and abstract objects and scene. The classes can be seen as a sequential extraction of meaning at increasingly higher conceptual levels. While this model provides a more organised arrangement of classes than Jorgensen, the subject categorisation is not as developed or detailed as Shatford/Panofsky. Experiments to test this model with Jorgensen's indexing template (Jorgensen et al., 2001) suggest it can accommodate a range of attributes and, under experimental conditions, guide description of subject content. However, as the authors admit, the experiments were limited and the indexers were students or the researchers themselves.

2.2.5.1 Summary and comparison of major models The three major frameworks are summarised in Table 2.2.

Table 2.2 - Image frameworks (after Laine-Hernandez & Westman, 2006)

Shatford / Panofsky

(1986) Jorgensen (1995/1998) Jaimes & Chang (2000)

Interpretative Art historical information

Syntax

Type/technique Perceptual

Colour, visual elements Global distribution

Colour, visual elements Local structure

Colour, visual elements,

location Global composition

Pre-iconography / generic of

Perceptual /

interpretative Objects, people

Semantics

Generic objects

Interpretative Content / story Generic scene

Iconography / specific

of Interpretative Content / story

Specific objects Specific scene Iconology / about Interpretative Abstract, people-related

and reactive attributes Semantics

Abstract objects Abstract scene

The models are similar in their hierarchical structure, although in Jorgensen’s framework the levels and classes are less well differentiated, and in the increasing knowledge and expertise required as the analysis moves from simple recognition of objects through to abstract or symbolic meanings. The Shatford/Panofsky model differs from the others in that it focuses exclusively on subject content and does not address perceptual attributes, such as colour. None of the models provides direction

on interpretation or aboutness, nor accounts for the interaction between levels and contextual or different domain knowledge.

While all the models provide useful frameworks for understanding the range of subject attributes viewers may describe, the Shatford/Panofsky model is the most suitable for this research because it supplies the best analysis of image subject content. The Shatford/Panofsky model provides a more developed and detailed subject categorisation and enables subject descriptors to be classified by the subject levels of specifics, generics or abstracts, and then by the facets of “who?”, “what?”, “where?”, and “when?”. Neither of the two other models has such a clear and developed structure for understanding subjects.

Furthermore, while Jorgensen (1996) trialled an indexing template based on her model this trial was not very successful, Experiments to test the Jaimes and Chang model with Jorgensen's indexing template (Jorgensen et al., 2001) were more promising but unlike the Shatford/Panofsky model these models have had limited use. In contrast, the usefulness of the Shatford/Panofsky model as an explanatory and analytic tool for subjects was shown in pioneering user research (Armitage & Enser, 1997). More recently, the Shatford/Panofsky model has predominated in a variety of current research, from user studies (Conduit & Rafferty, 2007; Rorissa, 2008), to investigations of tagging behaviour (Chung & Yoon, 2009; Golbeck et al., 2011; Ransom & Rafferty, 2011). Thus, an advantage of using Shatford/Panofsky is that it allows findings from this research to be more easily compared to previous investigations.

After considering the available models, it is clear that the Shatford/Panofsky model provides the best tool for subject content. Its strengths and prior usage by other researchers make it a good choice for this research.