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Apparently there is a logical ambiguity in "Someone who smokes can’t appreciate this wine.", but I'm currently unable to see it. Thoughts?
Belongs on language desk. The ambiguity is that "someone" might refer to one person whose name is unknown or otherwise unstated, or "someone" might be intended to mean "anyone". Loraof (talk) 01:26, 21 February 2016 (UTC)[reply]
There are two different interpretations of the sentence. The first is "there is at least one person who smokes and can't appreciate this wine"; the second is "any person who smokes can't appreciate this wine". These would be expressed in the predicate calculus in different ways. — Preceding unsigned comment added by 88.105.123.227 (talk) 20:42, 21 February 2016 (UTC)[reply]
When Pearson's r = 1.0 (perfect correlation), is the covariance always equal to the variance of both data sets? I think so. Also, is the standard deviation of both data sets always equal to the square root of 2? Schyler(exquirere bonum ipsum)20:39, 21 February 2016 (UTC)[reply]
The formula is covariance = r × [variance(first data set)]1/2 × [variance(second data set)]1/2. If r=1 and the two variances are the same, then the covariance equals that variance. If the variances are different from each other, then the question cannot be interpreted. The variances could be anything, not just 2. Loraof (talk) 23:22, 21 February 2016 (UTC).[reply]
