Differences in the Test Results of Two Test Rubrics in the Yes/No Vocabulary Test

The Yes/No vocabulary test (YN test) is a receptive vocabulary size test that comes in a form of a checklist where learners answer yes to the words they know. However, an inconsistency of the test rubrics has been found. That is, rubric type 1 says: “Write Y (yes) if you know the meaning of the word” while rubric type 2 says: “Write Y (yes) if you think that the word exists in English”. These 2 rubrics seem to require different levels of vocabulary knowledge from test takers. Rubric 1 may need more knowledge of the word meaning while Rubric 2 may need less (i.e. only having seen the word or even guessing). This led to the doubt whether or not the 2 rubrics yield the same YN test results. Therefore, a study was conducted to compare these two rubrics by administering 2 YN test versions, i.e. Rubric 1 YN tests and Rubric 2 YN tests, to 600 first-year students of a university in Nakhon Ratchasima, followed by a translation test as a concurrent validity test. After that, a semi-structured interview of 72 students was conducted in order to gain some insight of how they did the tests. The findings revealed that the results of Rubric 1 YN tests correlated better with the results of the concurrent validity test than those of Rubric 2 YN tests.