A locator algorithm creates a set of alternatives. Some locator methods provide multiple data items as subfields for every alternative. For example, the Order Group Locator provides multiple subfields such as the order number and order date; the Database Locator returns a database record set. In contrast, the Format Locator returns only alternatives for one subfield. For the Format Locator, you map the extraction field directly, whereas for an Order Group Locator, you map the extraction field to a locator subfield. For locators that provide subfields, each subfield has a confidence value that may differ from its alternative confidence.
The alternatives are weighed according to their confidence level. In the evaluation step, the locator compares the alternatives based on the additional settings you provide in the locator properties. Based on that evaluation, each alternative is assigned a confidence value between 0% and 100%.
For example, a date format is defined for a Format Locator that extracts the date MM/DD/YY, with two digits for the year. On the document, the dates "11/08/2004" and "12/07/04" are present. The format matches both dates. However, only the second date has a confidence of 100% because it matches perfectly, whereas the first date has a slightly lower confidence, such as 92%, because the format matches only "11/08/20" of "11/08/2004." Both alternatives are returned, but the better one is assigned to the field.