His reasoning for deducting the marks was that one of the studies in our textbook (Glanzer & Cunitz, 1966) involved participants recalling a list of 15 words (which was the same as the case study in the SAC) showed both the primacy and recency effect occurring at equal amounts. So, in this particular study, recall was better for items at both the beginning and the end of the list. However, when first introducing the serial position effect, the textbook says "The serial position effect is a finding that free recall is better for items at the end and beginning of the list than for items in the middle of the list. More specifically, the recall of items tends to be best for items at the end, and then the beginning, and worst for items around the middle... Experiments testing the serial position effect with different kinds of information, such as numbers or even sketches of objects, have consistently found a similar U-shaped curve with a strong recency effect". I showed him this and he justified it by saying this was only done on different information such as sketches and numbers and wouldn't be the case with a list of words.