Friday, September 4, 2020

Answer Scoring in Plates Across America®

Score Comparison Screen

The main premise of Plates Across America® is to complete a route in as few puzzles as possible. The general rule is:

The longer the answer, the further you travel. 

If you play the game in our "Race Mode", at the end of the race it will show all the puzzles with your and your opponent's answers side-by-side (see image at right). If you compare the scores, you might see something that does not match the "longer is better" rule. That is because there are some exceptions to that rule. This article explains the nuances of how we calculate the scores to help explain when the rule does and does not apply.  


The word "lemma" has multiple meanings, but here we mean it to be the "root" of word. For example: "wanders", "wandered" and "wandering" are related words and share the same lemma word "wander".  This concept is important in the scoring because we reward a good vocabulary more than someone's ability to creatively add extra letters (also known as "stemming" words). For example, someone should not get a higher score than you just because they to added a trailing "s" to pluralize the word.


The important part of understanding how plurals are scored is awareness that there are two different cases.

  • Case (1) Both the plural form and that word's lemma both match. In this case, pluralizing the word is somewhat superfluous and is only really serving to increase the letter count.
  • Case (2) The lemma of the word does not match and the pluralized form is required to be a valid answer. i.e., the ending "s" is required to make the word match.

For Case (1), the plural answer will be scored the same as the singular.  There is no penalty for using the plural form, but also there is no credit for the extra letters.

For Case (2), the plural answer will be ranked below all the other non-plural answers whose lemmas match the puzzle. For example, if the puzzle is "BDS", then "bedside" would score higher than "bedazzles" even though "bedside" has fewer letters. It is far easier to find a word with "B" and "D" and to pluralize it then it is to find a non-plural word with "B", "D" and "S".

Word Frequency

Once all the possible solution words are sorted out by whether they or not they are lemmas and their lengths, the next thing we consider is the word's frequency.  All other things being equal, the less frequently occurring words will score higher than more common, everyday words.

For example, for the puzzle "ADT", the word "audit" would score higher than "adult" even though they both have 5 letters. The word "audit" is not used as frequently as the word "adult" in normal usage. Note that the score advantage based on word frequency is not as dramatic as it is for the lemma vs. non-lemma case: it provides some advantage, but the word length scoring is more important.


Though word length is the prime element in determining the quality of the answer, it is not the only factor. Understanding the nuances of scoring will help you finish routes faster and score better in the game.

If you have not tried the game, and are interest, here's a link:

Game Demo

Happy Travels!

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