They used a mathematical method to quantify patterns contained within the symbols, in an effort to find out if they conveyed meaning.
Professor Lee described the basis of this method.
“If I told you the first letter of a word in English was ‘Q’ and asked you to predict the next letter, you would probably say ‘U’ and you would probably be right,” he explained.
“But if I told you the first letter was ‘T’ you would probably take many more guesses to get it right – that’s a measure of uncertainty.”
Using the symbols, or characters, from the stones, Prof Lee and his colleagues measured this feature of so-called “character to character uncertainty”.
They concluded that the Pictish carvings were “symbolic markings that communicated information” – that these were words rather than pictures.