Capitulo 6 Seguridad y Privacidad
6.3 Capas de seguridad en tarjetas RFID
The approach of content analysis is one of the most well established forms of text analysis among the empirical methods of social inquiry (Titscher et al. 2000). After World War II, sociologists and students of mass communication refined content analysis (Manning and Cullum-Swan 1998). However, it is somewhat difficult to give only one definition to this method due to the multiple and varied literature on
‘content analysis’ (Merten 1983). In the first place, content analysis referred only to those methods that concentrated on quantifiable aspects of text content. But, subsequently, the meaning of the term was extended to embrace all those procedures which operate with categories (syntactic, semantic or pragmatic) but which at least try to quantify these categories by classifying their data. The establishment of ‘qualitative content analyses’ (Mayring 1988) has also been added to the enormous range of procedures in content analysis. Titscher et al (2000: 55) argue,
One could describe as variants of content analysis all those methods of text analysis, which somehow approach texts by means of categories, since it is no longer a matter only of communicative content of texts but also of their (linguistic) form. In content analysis it is, therefore, more a question of a research strategy than of a single method of text analysis.
All the methods of content analysis have one core and central tool and this is the system of categories. Every unit of analysis must belong to one or more categories.
In the ‘classical content analysis’ (Ryan and Bernard 2000), once the researcher has selected a sample of texts, the next step is to code each unit for each of the themes or variables in the codebook. Thus, this produces a “unit-by-variable matrix that can be analysed using a variety of statistical techniques” (p.785). However, content
analysis has been weak in respect of capturing the context within which a text has been written (Manning and Cullum-Swan 1998). To counter this, Qualitative Content Analysis (QCA) was subsequently developed (see also Kracauer 1952).
QCA approach uses a categorisation process but it also comprises an investigation of underlying themes. In contrast to quantitative content analysis, QCA uses “the selection and rational organisation of such categories as condensed substantive meanings of the given text” (Kracauer 1952: 637). Moreover, in qualitative content analysis, the researcher has a reflexive and interactive role throughout the research.
Although the categories and variables initially guide the study, ensuring that it is systematic and analytic, other categories might also emerge if the researcher finds it necessary (Altheide 1996). The processes through which these themes are extracted are implicit and the extracted themes are illustrated in the form of quotations from articles or other documentary sources. What Altheide (1996) has called ‘Ethnographic Content Analysis’ (ECA) represents a codification of certain procedures that might be viewed as typical of the kind of QCA (Bryman 2001). Altheide (1996) argues,
ECA follows a recursive and reflexive movement between concept development and sampling-data, collection-data, coding-data, and analysis-interpretation. The aim is to be systematic and analytic but not rigid. Categories and variables initially guide the study, including an orientation to constant discovery and constant comparison of relevant situation, settings, styles, images, meanings, and nuances (p. 16).
Therefore, in ECA a categorisation process is operationalised similar to this of QCA, but it moves further with an investigation of underlying themes. Categories and variables initially guide the study, but other inductive categories emerge from the documents. The ethnographic character of the method allows the researcher to investigate the context wherein the author wrote the document and take into account the dialectic relationship of the key agent with his contiguous structures.
ECA focuses on collecting and analysing narrative data rather than following the positivist approach of classical (quantitative) content analysis. The major differences between these two approaches are presented below.
Table 4.3. Quantitative and Ethnographic Content Analysis (Adapted from Altheide 1996: 15)
Quantitative Content Analysis Ethnographic Content Analysis
Research goal Verification Discovery; verification
Reflexive research design Seldom Always
Emphasis Reliability Validity
Progression from data collection, analysis, interpretation
Serial Reflective; circular
Primary researcher involvement Data analysis and interpretation All phases
Sample Random or stratified Purposive and theoretical
Prestructured categories All Some
Training required to collect data Little Substantial
Type of data Numbers Numbers; narrative
Data entry points Once Multiple
Narrative description and comments
Seldom Always
Concepts emerge during research Seldom Always
Data analysis Statistical Textual; statistical
Data presentation Tables Tables and text
Quantitative content analysis pays attention to the issue of reliability of its measures, and on the validity of its findings through precise counts of word use (Sellitz et al 1964; cited in Silverman 2001: 123). However, Atkinson (1992) argues that one of disadvantages of the coding schemes used in methods such as content analysis is that because they are always based upon a certain set of categories, they build “a powerful conceptual grid” from which it will be difficult to escape (p. 459). Silverman (2001), commenting on this, argued that “while this ‘grid’ is very helpful in organising the data analysis, it also deflects attention away from uncategorised activities” (p. 123). However, ECA approach employs initial categorisation, but there is a greater potential for refinement of those categories and the generation of new ones with the development of understanding of the data. Thus, it allows inductive and deductive reasoning strategies to be utilised in conceptualising the data, allowing the researcher to revise regularly the themes or categories that are distilled from the examination of documents.