Sentence:  In repetitions of the experiment from couple to couple , the votes of the two persons in a couple probably agree more often than independence would imply , because couples who visit the museum together are more likely to have similar tastes than are a <WSD>random</WSD> pair of people drawn from the entire population of visitors . 
Meaning of the word marked with <WSD> tags:  lacking any definite plan or order or purpose; governed by or depending on chance