Why do we say "per egg" instead of "per clutch"

[wax32]

Well, per clutch just sounds bad! It sort've makes it sound (to newcomers) like you only have a 50% chance of getting "A SINGLE" spider in a clutch of spider x normal babies. If you say every egg has a 50/50 shot it sounds better, at least that's my story and I am sticking to it! LOL

[ed4281]

You get what you get.

[Dave Green]

It still never changes the clutch's statistics, despite what actually hatches. Real world doesn't change statistics

I never mentioned real world vs. statistics. The genetics/odds work per individual snake/egg. Of course you can apply it to a clutch, or 100 eggs, or 1000 eggs, etc. But at the end of the day it all comes down to the fact that each egg has a 50/50 shot of being a lesser or normal (using your example).

I used the coin flip example as it helps explain the odds. If I had 100 lesser x normal eggs incubating we can all guess that I would get close to 50 lessers and 50 normals but odds are only odds. If the first clutch hatches and I had 8 lessers and 0 normals it may change the results but it only means I beat the odds and it has no effect on future egg or clutch results.

I don't think it's a big deal either way...

[Simple Man]

Dave is explaining the same thing as myself but I'm going to give this a crack to help you out. I don't mean to offend you if you don't understand probability. I loved this stuff in school. So here goes...

Probability doesn't work the way you're thinking. I will just use your 1/2 or 50/50 for this explanation but you can follow along with the chart if that's easier. Probability means that the more eggs you have the higher percentage you have to hit your probability (50/50). That is because your odds are applied to each egg (not clutch). For smaller clutches your chances of hitting (50/50) probability are lower. The more eggs you have, the higher the (50/50) probability is that you will hit the expected number. That's why the odds are applied per egg. Even with 100 eggs you never will hit the 100% 50/50 probability just because of the way probability works and the fact that the odds are applied per egg. This is posted online @ www.cornguide.com by Serpwidgets to help breeders understand the chances of successfully hitting based on the amount of genes.I don't know any other way to help you understand it besides reading up on probability yourself. I don't mean this offensively.

Since the predictors give odds per egg, I though it might be useful to show the odds in a different way: expressed in terms of "probability of success."

What do I mean by that? Well, say your desired morph has a 1 in 16 chance according to the predictor. How likely are you to hatch one or more in a clutch of 4, or a clutch of 17? If you have a 1/64 chance per egg of some new triple morph from triple hets, what are your odds of hatching one or more if you've got 47 eggs to hatch?

In these charts "success" is defined as hatching any number of the desired morph... not just one, but one or more. All of the charts are the same thing, just "zoomed" to show finer detail for smaller numbers, and zoomed out to show the odds for up to 150 eggs. They include 1 in 2, 4, 8, 16, 32, 64, 128, and 256 "odds per egg" which will cover any combination of hets/homos for up to 4 recessive traits at a time.

First is for 16 eggs:
http://cornguide.com/odds/Eggs016.gif

So, to demonstrate how to read this, if your odds are 1/2 per egg you use the top green area. Follow the line up from the bottom depending on how many eggs you have. If you have 1 egg, your chance of success is 50%. With 2 eggs, it goes up to 75%. With 3 eggs you've got an 87.5% chance. And with 4 eggs, the odds go up to 94%.

Notice that the curve never reaches 100%... probabilities are not guarantees. Which probability equates to saying you "should" succeed? Well, it's up to you to decide what level of "risk" you are comfortable with in your own projects. But these make more sense of the predictions because it's not often that you plan on hatching a single egg at a time.

Regards,

B

[angllady2]

Well to me, if you have say a 1 in 64 chance at a morph, no ball python I know is going to have 64 eggs at one time!

So, by saying the chance is per egg, it seems easier to wrap your head around, at least to me. To me, saying per clutch means my ball MUST have 64 eggs and then I get the morph I want. By saying per egg, that to me means I could get that morph in my first 4 eggs, or not get it at all no matter how many eggs I get. This is more realistic to me. Does that make sense ?

Gale

[Redneck_Crow]

You know what? I don't really care which way people say it. As long as I can understand what they mean it's all good to me.

[rabernet]

LOL, I didn't imagine when I posted earlier today in a thread about the probability being per egg, that it would spark this conversation, but it's turned out to be a pretty interesting thread.

I don't think I really need to add much in way of explanation, because I don't think I could explain it any better than it has already been, by prior posters.

[OhhWatALoser]

Ok ill start with can you guys please stop repeating yourselves about the per egg. We all understand that and its not what im trying to discuss, im trying to understand why saying "statistically you should get 50% lesser 50% normal" is wrong, why does it need "correcting". I understand the odds are per egg. an odd number egg clutch its obviously impossible to have a 50/50. but again, statistically what should you get?

ok ill try this fill in the blank "statistically you should get _______ per clutch"

I never mentioned real world vs. statistics. The genetics/odds work per individual snake/egg. Of course you can apply it to a clutch, or 100 eggs, or 1000 eggs, etc. But at the end of the day it all comes down to the fact that each egg has a 50/50 shot of being a lesser or normal (using your example).

I used the coin flip example as it helps explain the odds. If I had 100 lesser x normal eggs incubating we can all guess that I would get close to 50 lessers and 50 normals but odds are only odds. If the first clutch hatches and I had 8 lessers and 0 normals it may change the results but it only means I beat the odds and it has no effect on future egg or clutch results.

I don't think it's a big deal either way...

Big deal not really, but If no one cared, no one would keep "correcting" others.

LOL, I didn't imagine when I posted earlier today in a thread about the probability being per egg, that it would spark this conversation, but it's turned out to be a pretty interesting thread.

I don't think I really need to add much in way of explanation, because I don't think I could explain it any better than it has already been, by prior posters.

It's posted in a lot of threads, I was going to respond in the thread, but figured it be better as its own topic

[Highline Reptiles South]

Compare it to flipping a coin. If I flipped heads 10 times in a row that has no effect on the 11th flip. The 11th flip is still a 50/50 shot.

This is the perfect answer. A+

Statistically - using a large enough sample - they should tie out.

To respond to Ohwhatloser. People say per egg because a typical clutch is statistically not a large enough sample for the odds to work out. I'm too many decades out of my statistics 401 class to remember the formula, but there is calculation that will determine a statistically accurate sample size...and its a boatload bigger than the biggest clutch size...hence - per egg.

[JLC]

Ok ill start with can you guys please stop repeating yourselves about the per egg. We all understand that and its not what im trying to discuss, im trying to understand why saying "statistically you should get 50% lesser 50% normal" is wrong, why does it need "correcting". I understand the odds are per egg. an odd number egg clutch its obviously impossible to have a 50/50. but again, statistically what should you get?

ok ill try this fill in the blank "statistically you should get _______ per clutch"

I get what you're saying.....and here's my take on the answer:

It's actually pretty rare that someone says "Statistically you should get ____ per clutch." And even that statement isn't really correct. There is no "should" in statistics. It would more accurately read "Statistically you could get...." But again...people rarely ever actually express it that way.

More often you'll hear, "You'll get 50% lessers in a lesser x normal clutch" ...or something along those lines. The ways it is most commonly expressed leaves the impression to a newbie that they WILL get half lessers and half normals in their clutch.

And the simplest way to fix that misunderstanding is to explain that the genetic statistics are calculated PER EGG. Each egg is its own little formula, independent of the whole clutch.

If you have a lesser x normal clutch that has 12 eggs in it....what are the odds that you'll actually hatch out 6 lessers and 6 normals? I don't know the formulas, but I'll bet the odds of that outcome are not 50/50.