[GNC] Best match probability calc is too pessimistic

[David Reiser]

I keep my records based on transaction date. I want to know when I bought something, not when a credit card company gets around to posting it. Online transactions will sometimes post on the transaction date, but in-store transaction almost never do. I almost always enter transactions in gnucash before I download transactions from the bank. With most transactions entered prior to downloading, finding mistakes and missed transactions is much easier.

Under the transaction matcher behavior in gnucash 4.0, a transaction which posts one day after the transaction date gets a best match probability score too low to ever meet the auto-match threshold during an ofx import processing run. For example, I bought some stamps at the post office on July 2. The credit card company posted the transaction on July 3. When I imported transaction on July 5, the transaction showed up in the matcher window with no probable match acknowledged.

From my perspective, transactions posting within 3 days of the transaction date should still get a match score of 6. One day after transaction ought to be 8. One of the grocery stores I go to frequently has never posted the charge to the credit card company the next day. Sometimes there’s only a 2-day gap, but it is frequently 3 days. I suspect the difference between 2 and 3 days is related to how late in the evening I go shopping.

And on the extreme end, for a checking account transaction, if the imported check number (complicated by bank-prepended zeroes) and amount match exactly, and the date in gnucash is within 180 days of the bank’s date, then the transaction should still have some usable match score. In the U.S., the bank will still pay that check. I have had friends sit on checks for excessive lengths of time.

Dave
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Dave Reiser
dbreiser at icloud.com