we can use Pinterest API and tag for the conversion process, thus the same event may be counted twice. Deduplication removes duplicates which improves the accuracy of the conversions.
Pinterest cannot know if a conversion reported by the Tag and another reported by the API for Conversions are the same.
Because Pinterest recommends using both the API for Conversions and the Pinterest Tag, deduplication is an essential part of the implementation process. It helps to avoid double-counting of a single event when it’s sent through multiple sources, such as the Pinterest Tag and the Pinterest API for Conversions.
For example, if a user triggers an add to cart event and the tag reports the data using 123 as the event ID. Later, their web server reports the conversion to the API and uses 123 as the event ID. When Pinterest receives the events, Segment looks at the event IDs to confirm they correspond to the same event.
By using deduplication advertisers can report conversions using both the tag and the API without having to worry about over-counting conversions. This will result in more conversions being attributed than either alone, because if the tag doesn’t match an event, but the API does (or vice versa), the event can still be linked.