Take the following as truth: Let us consider the dust-jacket blurbs of Cobuild, CED , and two other native-speaker  the British Longman Dictionary of the English Language (Longman , 1984) and the American Webster's Ninth New Collegiate Dictionary ( W9 , 1983).
Then the following statement: "The cover of American Webster's Ninth New Collegiate Dictionary has errors, I'm sure there are errors inside also." is true, false, or inconclusive?
Answer: Inconclusive