Breeding rant: What are the odds!?

[Howmander]

Okay, so I hatched 25 Froakies this evening and ran their stats through a stat calculator so I got the exact number of all the stats, but out of those 25, 3 of them had the IV spread 31/31/31/31/30/31 and an additional 2 had the IV spread 30/31/31/31/31/31 It had nothing to do with the parents because the parents were 31/31/31/31/31/31 and 31/31/31/31/4/31 so how insane and unlikely was it to get something like that 5 times?!

So, what was the most insane, frustrating, lucky or infuriating thing you've experience while trying to breed a perfect pokemon?

 

[J9794]

Let's see, first, what are the chances to pass down the bad IV (4)?, if you pass 5 IVs, then you have a 1/6 chance of passing the spdef, and if the spdef IV is selected, you have 1/2 chance of passing the bad one, as those events are independent, the chance of both occurring at the same time is: 1/2 * 1/6 = 1/12.
So you have a 11/12 chance of passing down 5 perfect IVs, then we have a random IV that can take 32 different values (from 0 to 31), again the calculation of this last IV is an independent event to the calculation of which IVs are passed, so the chance of both occurring at the same time is 11/12 * (chance of getting 30 or more in the last IV). The chance of getting 30 or more is 2/32 = 1/16, so the chance of getting a poke with 5 31s and a 30 IV is 11/12*1/16 = 11/192, which is around 5,73%.


Okey, so the chance of getting ONE poke with 5 31s and a 30 iv is 11/192. Now, what's the chance of that happening 5 times in 25 tries?:
There's a formula to know this, and that formula is

Where n is the amount of tries, X the amount of successful events, and P the chance of ONE succesful event happening.
n=25
x=5
p=11/192
that gives us (according to an online probability calculator I googled) : 0.010077

That means, around 1,01%.

Damn, if I did the math right, you are very lucky ^^.

Please, if somebody noticed a mistake in my explanation correct me.

 

[Howmander]

Let's see, first, what are the chances to pass down the bad IV (4)?, if you pass 5 IVs, then you have a 1/6 chance of passing the spdef, and if the spdef IV is selected, you have 1/2 chance of passing the bad one, as those events are independent, the chance of both occurring at the same time is: 1/2 * 1/6 = 1/12.
So you have a 11/12 chance of passing down 5 perfect IVs, then we have a random IV that can take 32 different values (from 0 to 31), again the calculation of this last IV is an independent event to the calculation of which IVs are passed, so the chance of both occurring at the same time is 11/12 * (chance of getting 30 or more in the last IV). The chance of getting 30 or more is 2/32 = 1/16, so the chance of getting a poke with 5 31s and a 30 IV is 11/12*1/16 = 11/192, which is around 5,73%.


Okey, so the chance of getting ONE poke with 5 31s and a 30 iv is 11/192. Now, what's the chance of that happening 5 times in 25 tries?:
There's a formula to know this, and that formula is

Where n is the amount of tries, X the amount of successful events, and P the chance of ONE succesful event happening.
n=25
x=5
p=11/192
that gives us (according to an online probability calculator I googled) : 0.010077

That means, around 1,01%.

Damn, if I did the math right, you are very lucky ^^.

Please, if somebody noticed a mistake in my explanation correct me.

One flaw in your equation though is that (in those examples) the bad IV was NEVER passed down. The only bad IV in either parent was in the Sp Def and it's IV was 4, not 30, so in all those instances the bad IV was never passed down, but rather 30 was randomly generated 5 times (in either Sp Def or HP) within 25 offspring

 

[Sebastian_Sommer]

I don't have much complaint about XY's breeding mechanic cause it's leagues better than BW2. Try breeding your pokemon to 5iv without a destiny knot. Even with a perfect iv parent, you will still have a hard time trying to get one 4iv pokemon from a single box (around 30 eggs). This is especially bad when I realized that the pokemon I was breeding at the time, didn't have a egg move that I had wanted and I had to start all over again...

 

[LyokoGirl5000]

An hour ago, I decided to breed the perfect Gastly, Timid with 6 IVs. Five minutes ago, I got a 6 IV Gastly. With a Naive nature. I mixed up my Timid Gengar with a different one. Now I either have to start over or keep breeding until I get a Timid Gastly and switch to that one as the parent. I sure hope people won't mind getting 4-5 IV Gastly rejects on Wonder Trade because that's all I'll be doing for the foreseeable future.