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Calculating the Mean Time Between Failures?
Blue Booger asks: "I was looking over some fibrechannel hard drives and noticed that the Mean Time Between Failures was rated at 1.2 million hours. I thought that was pretty high, and figured it up to be close to 137 YEARS!! I went to check some regular IDE drives just for comparison, and they were rated at 500,000 hours (57 years). Now, as I understand it, this is supposed to be the average time that you can expect the drive to last before failures. I rarely have an IDE drive last more than 4 years, and my record is 10 years, so what is the deal? BTW, that is 57 years running 24 hours a day...the MTBF is rated as power on time. Here you can find Western Digital's glossary that defines the term MTBF (pdf). Here you can find a spec sheet on one of their 20GB IDE drives. I checked, and Seagate also lists similar MTBFs. How the heck are they coming up with these numbers?"
I would think proper grammar usage would be a prerequisite for being a MENSA member.
Mmmm-hmm. You understood it; the "grammar" rule you are citing is artificial. English isn't created by a bunch of old guys in Universities; it's in every mind, and it's constantly changing. "Don't split infinitives," "don't use no double negatives" (an especially stupid rule, considering you have to think about it to not understand the sentence!), and the like tend to do little more than limit the expressiveness of English.
Apparently you just need to feel good about yourself or something. ("Look at me! I pointed out the error of a Mensa member....wheeeeee.....")
Obligatory plug of a book that will explain it: The Language Instinct, second-to-last chapter.
Also, mods: ad hominem, offtopic (this is as well, so fire away if you see fit)