Grey literature

When gray literature (English fugitive literature, gray literature or gray literature ) is called in the library science books and other publications that are not sold through the book trade. These publications are often published by clubs, organizations, or the like. German titles are released in Germany in the German National, Series B, .

Publications on the Internet are not fully captured by the German national bibliography.

Also a large part of scientific work remains unpublished and is only available directly through the appropriate institutions. Reasons for this may be that epistemological minimum requirements (eg, statistical significance ) are not met, or the contents of the work ideological conceptions contradict and are censored. Also in the GDR were noisy to some authors Scientific texts have been censored, Jürgen Bortz and Nicola Döring write this at all:

" Interestingly, the gray literature in the former GDR as not censored literature usually have a higher scientific value than the official, state-controlled literature. "

Importance of gray literature in the research

If you want to get an overview of the state of research on a topic, often one uses so-called meta-analysis and overview of work (review article). In meta-analyzes of several statistics are combined into a large sample with smaller samples and formed on their results, a mean value. In summary work more research will be summarized on a topic. Here the work is, however, not statistically processed but content related to each other and discussed.

However, if only published works included in meta-analyzes and survey work could erroneously appear to be a topic of matching, as they are actually the scientific results. In extreme cases, non-existent differences between groups or observed correlations could be observed only by chance, while studies in which nothing of the sort could be observed, were never published. Due to the probability theory, ie by random unexplained observations would then falsely cause (causally ) explains, or at least not described as truly random. If some unpopular opinions not get a word through censorship, arises erroneously the impression of unanimity because disagreements are not considered.

This false impression is known as publication bias. To counteract a possible publication bias, unpublished work should be included. " The result of a meta-analysis is of course dependent on the selection of the included primary studies ." The same applies analogously for overall work ( reviews).

Procurement problems of gray literature

The problem to get to gray literature, treated MC Rosenthal.

Examples

• Programmes
• Conference Reports
• Institute fonts
• Preprints
• Catalogs, reports and plans
• Fanzines
• Leaflets
• Occasional writings
• Sites
• Not (yet) published theses, term papers, dissertations and other texts from the university environment, which directly or via other distribution channels to their target group.
• Samizdat, not conforming to the system literature in the USSR and later in other socialist countries, which was handwritten, typed or copied photocopied and passed on unofficial channels