Relevance Ranking Explained
Sometimes search results don't seem relevant....
Sometimes the results you get can be a bit puzzling because they don't seem to be entirely relevant to your search. Archives are not like books and journals; archives are collections of materials brought together by individuals and organisations, and therefore they may contain all sorts of materials on many different subjects. The archive of a botanist, for example, may be about many more subjects that botany because it might contain personal documents, maybe letters to friends and family, that are about many different things.
Archives are not necessarily based around a subject; they are collections brought together by individuals or organisations. the personal correspondence of a famous industrialist, for example, could cover 100's of subjects, from domestic life to leisure interests, in addition to industry.
Our relevance ranking takes into account the number of times the search term(s) appear and it also weights certain fields, such as the title and the index terms. We can only go by the descriptions that we have. For example, an archive may be substantially about 'urban planning' but it may not use this term and instead refer to 'city planning'.
Sometimes phrases you use to search don't match very well with our descriptions...
It may be that your actual search term is not found in many collection descriptions. But just because a collection description doesn't include the exact search term, it may still be relevant to your research, and we want to try to bring back all relevant results for you.
If you search for public healthcare we have very few descriptions that have this phrase in them, so the descriptions you get back will have 'healthcare' or 'public' in them as separate words, but they may not be about public healthcare. There are many descriptions that refer to public health so this is a better search term:
"public heathcare" - not used much as a phrase within descriptions
public health - many results - may not all be about 'public healthcare' as the words may appear separately
"health policy" - may be a useful term, and is a recognised subject term
health - will get far more results and the filter could then be used, e.g. filter by 'health services'.
welfare - a broad search which could be narrowed by e.g. 'child welfare'.
- Archive collections are described by archivists and the level of detail and words used will vary. It is very hard to reflect the whole archive accurately in a description when it is very big and diverse.
- Descriptions often contain historical and biographical information about the collection and the people, places and things mentioned in the archive. These can be long, free-text descriptions and they will affect the results of a search. For example, a biographical history may refer to someone's background in 'genetic research' but the actual collection may not be about this work, so it may not cover genetics to any significant degree, but it might still be useful background for your research.
- Archives can contain surprising things, so you sometimes need to put more thought into searching. Books are written about subjects, and have tables of contents to summarise the topic(s), but archives collections are not usually consciously put together for future researchers; they reflect activities that were carried out for other reasons.
- Your search term might not match any of our descriptions, so our system will try its best to find near matches, but they might not be what you want (the system can only do its best!)
- You may find you need to broaden out your search and then narrow it down again. For example, if communist ideals doesn't seem to work very well, try a search for communism and then use our filter to try things like east-west relations, socialism or human rights.