Faulty Comparison

If you try to make a point about something by comparison, and if you do so by comparing it with the wrong thing, you commit the fallacy of faulty comparison or the fallacy of questionable analogy.

Example:

We gave half the members of the hiking club Durell hiking boots and the other half good-quality tennis shoes. After three months of hiking, you can see for yourself that Durell lasted longer. You, too, should use Durell when you need hiking boots.

Shouldn't Durell hiking boots be compared with other hiking boots, not with tennis shoes?

False Analogy

When reasoning by analogy, the fallacy occurs when the analogy is irrelevant or very weak or when there is a more relevant disanalogy. See also Faulty Comparison.

Example:

The book Investing for Dummies really helped me understand my finances better. The book Chess for Dummies was written by the same author, was published by the same press, and costs about the same amount. So, this chess book would probably help me understand my finances.