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backstop20
10-29-05, 03:17 AM
It's actually a stupid question. :o

K = 5
BB = 0

Is the ratio 5 or 0?

Thanks!

stupidpunchline
10-29-05, 09:11 AM
It's actually a stupid question. :o

K = 5
BB = 0

Is the ratio 5 or 0?

Thanks!

K/BB is exactly how it reads # of strikeouts divided by # of walks.

Your ratio is mathematically invalid because a number divided by 0 can't exist. If a pitcher has 5 strikesouts and 1 walk, the ratio is then 5:1 or 5.00, depending on your preference of expression. If a pitcher had 0 strikeouts and 5 walks, the ratio is 0:5 or 0.00, as zero divided by another number is also zero.

Wang's Groundballs
10-29-05, 02:05 PM
It would be infinite.

bakntime
10-30-05, 03:08 AM
It would be infinite.It wouldn't be infinite, but as stupidpunchline said, it would be mathematically invalid, or undefined.

5 divided by zero has no solution, because you're basically saying "how many times does zero go into 5". No matter how many zeros you take, you'll never "get" to 5. Another way to look at it:

if 5/0=x, then x (times) 0 must equal 5. What number times zero equals 5? No number. Not even a number that approaches infinity.

Archer1979
10-30-05, 08:30 AM
It wouldn't be infinite, but as stupidpunchline said, it would be mathematically invalid, or undefined.

5 divided by zero has no solution, because you're basically saying "how many times does zero go into 5". No matter how many zeros you take, you'll never "get" to 5. Another way to look at it:

if 5/0=x, then x (times) 0 must equal 5. What number times zero equals 5? No number. Not even a number that approaches infinity.

How does your math module still work at 3:30 am? :lol:

This is actually the same concept as Mike Remlinger's first two outings with the Red Sox this year. To refresh your memories, after two appearances, he had given up six earned runs and recorded no outs.

E.R.A. = infinity, despite the fact that the denominator (in this case, innings pitched) was 0.

PaulieIsAwesome
10-30-05, 11:46 AM
It wouldn't be infinite, but as stupidpunchline said, it would be mathematically invalid, or undefined.

5 divided by zero has no solution, because you're basically saying "how many times does zero go into 5". No matter how many zeros you take, you'll never "get" to 5. Another way to look at it:

if 5/0=x, then x (times) 0 must equal 5. What number times zero equals 5? No number. Not even a number that approaches infinity.

To be a math nerd about it, it isn't terrible to say that the ratio would be infinity. The question here is really the limit of 5 over x as x goes to 0. The thing is, your number of walks can only be positive, so x is restricted to positive values. And 5 over a tiny, tiny, tiny positive value is positive infinity.

If the denominator could also be negative, then it would actually be undefined.

bakntime
11-02-05, 03:20 AM
To be a math nerd about it, it isn't terrible to say that the ratio would be infinity.It wouldn't be right, either ;) While you do have a valid point because walks can't be negative, in "practice" I think it's more applicable to give the indeterminite response for discrete integral values such as the ones we're dealing with here.


The thing is, your number of walks can only be positive, so x is restricted to positive values.restricted to positive values - and zero - but I know what you're saying.


And 5 over a tiny, tiny, tiny positive value is positive infinity.Not exactly... 5 over a tiny, tiny positive value is a very large positive value. Infinity is not pre-defined as a number, it is a tendancy. If you were asking what your K/BB ratio is "kinda like" or what it's "near" when your BB total is zero, then it would be very large (approaching infinity), but since we're talking about a discrete, integral strike out total over a discrete, integral walk total, (5/0), there's no way to evaluate that discrete fraction without a much more complex context, one which, in this case, seems excessive and unnecessary.

If we wanted to add that complexity in such a situation as this, where walk totals can't be negative, we could reasonably assign the word "infinity" to mean any fraction with a zero in the denominator, since such a fraction "tends" toward the infinite the smaller our denominator gets, but I think that's complicating a situation that doesn't "deserve" so much complexity... we would have to violate the basic field principals and axioms of the set of integers just for the sake of defining infinity as a specific value. For example, if we say 5/0=infinity, then, according to basic axioms of numbers, 0*infinity should = 5, when clearly it does not. Breaking basic "laws" such as these seems excessive in the given context of walks and strikeouts.

And rather than say "his K/BB ratio of 5/0 tends towards infinity," it makes more sense to say "his K/BB ratio is indeterminite... let's wait to discuss his K/BB ratio until we get a stastically significant sample size so as to make that ratio meaningful" :D

backstop20
11-02-05, 08:30 PM
Thanks for the responses!

I was making battery game logs for 2005 and wasn't sure what to put there.
Then I found the divisional game logs which use 0.00 for that scenario.
But, I guess that's wrong! :)