“How sure are you? Fifty percent? Seventy-five percent? Ninety percent?”
Huh? I was doing some contract work. After being asked about some particular detail, I promptly gave the best answer I could, saying that I was “quite sure” it was accurate. When asked to give a percentage, I almost laughed. He just had to be kidding. Isn’t that something only junior highers would say?
I came to find out, after polling three of my four siblings, that not only were fully-grown adults guilty of asking this, but they asked in all seriousness. Rebecca said it reminded her of the “On a scale from one to ten, how much pain are you experiencing?” question asked by medical professionals. There’s an illusion that the number means something concrete when it’s actually very subjective and, in my opinion, less useful than a normal answer. Clearly, we place too much value on our ability to quantify and rank things.
I recall a professor who was against reporting statistics to three or more decimal places. He was always concerned that a long train of digits would give a false sense of accuracy and precision, leading an undiscerning reader astray. That’s what I see happening when someone says, “I’m eighty percent sure of X” as if there’s a Federal grant worth of data behind it. It’s a meaningless number. In contrast, saying “I’m pretty sure” is upfront about the situation. “Here’s my personal opinion. Take it, or leave it.” The other party’s forced to decide whether or not to trust what he hears. In both cases, there’s risk, but I guess some people feel more secure about a phony statistic than an honest opinion.