Rank results
The default rank option for a search is No ranking. This means that records retrieved in a search are numbered and listed in the order they were added to the database. The most recently added record appears first.
Organize your results list by selecting the Relevance or Date option in the Rank by: field. The 1000 top-ranked records will be displayed on your list of results.
Select a rank option in Group_Catalog or WorldCat
When performing an Advanced or Expert search, you can rank the results of your search by any of the following options:
| rank | 說明 |
|---|---|
| Number of Libraries | Records are listed by the number of libraries that hold the item. Commonly held items (items held by the most libraries) display first on the list. Note: For items held by 5 or more libraries, records are listed in exact number order. Records held by 4 or fewer libraries appear at the bottom of the results in random order. |
| Relevance | Records are scored and listed by relevance rank, a measure of how closely a record matches your search terms. The most highly ranked, and therefore, most relevant records display first. See Relevance ranking for more information. |
| Date | Records are listed by year of publication. The most recently published records display first. |
| Accession Number | Records are listed by database record number. The most recently added records display first. |
The default rank option is Number of Libraries. You can select another ranking option with each search.
All records of a results set display when the default option is used. For other ranking options, only the top 1000 records of the results set are displayed.
Relevance ranking
Relevance ranking organizes the results of a search to display the most relevant records at the top of the results list. Moving down the list, records become less and less relevant to the key search terms entered in the search. Only the top 1000 ranked records are displayed.
Though the default reverse chronological display lists the most recently added records first, they may not present the most relevant information on your topic. For example, if you search for information on the unification of Germany in 1990, information on the aftereffects may appear first on the results list. However, if you choose to focus on the 1990 unification event itself, a rank by relevance can bring to the surface those records which focus most heavily on your terms.
Relevance ranking in FirstSearch is based on a number of criteria:
- Search terms in the record. The number of search terms that appear in the record. The relevance weight increases as more of your search terms appear in the record.
- Proximity of the terms. The distance between search terms in the record. The relevance weight decreases as more words appear between search terms.
- Uniqueness of the terms. The number of times a search term occurs in a record relative to the number of times the same term occurs in the rest of the database. If the search term occurs 10 times in a single record and 100 times in the entire database, that record's relevance weight will be higher than for a record in which the term appears only once.
The combination of these weighted criteria are used to evaluate a record's likelihood of satisfying the intent behind your search.