When testing URLs we score each url in the index as a possible match. We then take the highest scoring result and use that. As the scores decrease through the results file, the less likely it will be a valid match.
Matches take about 1-2 minutes per 1,000 urls in the dataset. However this depends on the match criteria. The more complex the matching algorithm the longer it takes.
This depends on the datasets. We have seen 85-90% perfect matches on datasets of about 2,500 urls. The site was an E-commerce site with lots of descriptive long urls
This is a 'New URL' that has been matched against the old url dataset
After the matchset has completed successfully
We strive to make the best matches possible, but are always tweaking and changing our algorithms. If the results are not as good as you had hoped, please contact us and we can see if there is anything we can do to improve it.