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Post by Glenn on Nov 1, 2013 10:43:34 GMT -6
Damn, I'm posty this morning. Here's a bell curve for PicketWire
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Post by Glenn on Nov 1, 2013 10:45:04 GMT -6
Here's one without the std dev. demarcations. I like it because it is colored up to show that "too much" is as bad as "too little"
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talin
Yearling
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Post by talin on Nov 1, 2013 11:07:18 GMT -6
My textbook makes it here today so I am going to see how rusty I am in math and statistics.
The problem I had before is I looked at the BIF formulas but then could not figure out how to apply the GE EPD changes although it didn't take long to realize if you have good EPD's it makes them better bad not so much.
Has anyone any idea of how the GEEPD modifiers work with the formulas?
DH
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Deleted
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Post by Deleted on Nov 1, 2013 17:48:31 GMT -6
EPD bulls Work good for these guys. Probably what I need to be doing. Probably sell bulls for 4x or better than what I do. Sell bulls to the studs...ect... My dumb ass can't get past how they walk though.... nice and uniform.
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Post by picketwire on Nov 1, 2013 21:56:49 GMT -6
"The range of observations on an animals progeny have nothing to do with how fast the accuracy of the EPD increases, nor does it have anything to do with the possible change value for an animal."
lazyycross/Dave K. I am not entirely certain that I said that range of observations had anything to do with how fast the accuracy changes.
"Yours is a common misunderstanding. "
"The taller, narrower bell curve you described from the older sire summaries was a graphical representation of how the possible change gets narrower with more observations, not to be confused with a narrower range of performance in the progeny of the animal."
That is precisely one of the point's I was trying to make. Probably didn't make it very clear as I am no word wizard.
"To take an extreme example. If bull A's 3 progeny weighed 400, 500, and 600 pounds at weaning, and bull B's 3 progeny weight 475, 500, and 525 pounds at weaning, the sire's accuracies and possible change values would change at the same rate given everything else being equal. "
No argument from me there, but if say bull B's progeny had that tight of grouping with 330 weights submitted instead of just three, then would the additional pedigree information from the additional progeny as well as the contemporaries not result in more accuracy?
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Post by picketwire on Nov 1, 2013 22:00:28 GMT -6
Glenn, thanks for posting the bell curves especially the top one.
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Post by George on Nov 2, 2013 9:18:35 GMT -6
George, You misunderstand. No, it is YOU that misunderstood - apparently you don't always recognize sarcasm when you read it! This is relatively complex algebra, George. Most people are not exposed to this level of algebra as undergraduates unless they are statistics majors. Universities that specialize in Animal Breeding PhD's are beginning to teach this level of algebra to Master's students, but most of the understanding doesn't really come until the PhD level. I've only met a handful of seedstock producers in the last 20 years that can converse at an articulable level regarding this level of algebra, maybe 4, actually, but really only 2, that REALLY could. That isn't a statement of disrespect, and in no way disparages the knowledge of producers, it is just a simple fact that we are talking about "high" math, and it takes specific training to understand. I trust that A*B = AB and that 0.5A*B = 0.5AB, and that 0.5AB will ALWAYS be less than AB. The formula for accuracy that is partially derived from heritability, that ends up in the possible change equation is the same concept, only with higher level math. An overestimated heritability will lead to a decreased possible change range and greater probability of the true BV being different than the EPD. The other consequence of an overestimated heritability, is that the EPD spread will be wider, which can be erroneous as well; this would overemphasize small differences among animal leading to even more "bigger is better" mentality. Dave K. I ought to forward this part of your post to all my former professors and fellow students that were in class with me back when I got my civil engineering degree(specialty in hydrology). I'm sure the fact that YOU are trying to school ME in Algebra(or Statistics or Calculus or Physics or Differential Equations) would make them laugh their asses off! Some people get a few letters following their name and their head sometimes becomes so large that they can't even get through a door! Yep, they just gotta do something for all those POOR PRODUCERS who just don't understand!
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Deleted
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Post by Deleted on Nov 2, 2013 13:29:32 GMT -6
You guys lost me on this thread about the time picketwire started discussing bell curves. But it does bring back some memories. "leading to even more "bigger is better" mentality." Read more: herefordtalk.com/thread/1769/epds-work?page=2#ixzz2jW3ulYanTo this day, every time I read or hear the phrase that bigger is not always better or bigger is better I cringe because of the memories that phrase brings back and how I learned that it really doesn't do much good to converse with people who don't give a piddle what your talking about. I was, maybe, 25 years old. Northeast Nebraska was in the midst of the farm crisis and everyone was searching for answers. There was a very loosely organized farm group that had first started as a committee to help troubled farmers mediate debt difficulties with lenders. I volunteered to speak to the local community club (a chamber of commerce type group) about some of the activities. I had a speal all prepared and there was one line where I said something like it was a myth that bigger is better in terms of farm operaton size. There were two little old women sitting at a table near me and when I said it was a myth that bigger is better they looked at each other and started giggling. It was all I could do to keep from laughing myself and to finish my speal. I knew they weren't giggling about farm size and they really didn't give a damn what I was saying. Every time I read or hear that phrase, I picture those two little old women giggling and remember how stupid I was. At least I got all that activism garbage out of my system at a young age.
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Post by bookcliff on Nov 2, 2013 17:46:19 GMT -6
I am just a damned old pasture cowboy but............................................
don't sit there and tell me that me that I need to pony up $$$ for 50K DNA work to make my EPD's more accurate 2 years ago at KC and then tell me this year accuracy don't mean a damn thing and I may have to go to 77K.
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Deleted
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Post by Deleted on Nov 2, 2013 18:00:38 GMT -6
I am just a damned old pasture cowboy but............................................ don't sit there and tell me that me that I need to pony up $$$ for 50K DNA work to make my EPD's more accurate 2 years ago at KC and then tell me this year accuracy don't mean a damn thing and I may have to go to 77K. Is that the message from this years convention?
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Post by lazyycross on Nov 2, 2013 18:12:08 GMT -6
Well George, if you understood the math, why did you use sarcasm to respond to something that you should understand? I wouldn't have missed it if you would have said, "I understand."
For that matter, why aren't you jumping in to help the understaning of the group?
I was hesitant to participate in this one, and it's pretty obvious I shouldn't have.
It turned the way I thought it would.
Dave
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Post by strojanherefords on Nov 2, 2013 19:21:56 GMT -6
Nay, an I tell you that, I'll ne'er look you i' the face again: but those that understood him smiled at one another and shook their heads; but, for mine own part, it was Greek to me. I could tell you more news too: Marullus and Flavius, for pulling scarfs off Caesar's images, are put to silence. Fare you well. William Shakespeare Kind of sums up my thoughts on EPDs.
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Deleted
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Post by Deleted on Nov 2, 2013 20:54:15 GMT -6
I am just a damned old pasture cowboy but............................................ don't sit there and tell me that me that I need to pony up $$$ for 50K DNA work to make my EPD's more accurate 2 years ago at KC and then tell me this year accuracy don't mean a damn thing and I may have to go to 77K. As we have discussed before TK, 90% of the people we sell cattle to don't really care about any of this "fancy stuff" or EPD's. They just want cattle that will work, are problem free, and the reputation that stands behind them.
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Post by mrvictordomino on Nov 3, 2013 0:12:36 GMT -6
I am just a damned old pasture cowboy but............................................ don't sit there and tell me that me that I need to pony up $$$ for 50K DNA work to make my EPD's more accurate 2 years ago at KC and then tell me this year accuracy don't mean a damn thing and I may have to go to 77K. As we have discussed before TK, 90% of the people we sell cattle to don't really care about any of this "fancy stuff" or EPD's. They just want cattle that will work, are problem free, and the reputation that stands behind them. Sounds like a good policy to me.
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Deleted
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Post by Deleted on Nov 3, 2013 6:01:05 GMT -6
Bear with me for a moment and let us assume that EPD'S work.
1) Would breeders that truely had higher numbers receive more buyers? 2) Do average breeders suffer because customers don't know what EPD'S to select considering their management and enviorment? 3) Working correctly, what numbers would you strive to keep in your herd? 4) Are you committed to a bloodline regardless if EPD'S did or did not work?
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Post by bookcliff on Nov 3, 2013 8:33:05 GMT -6
I am just a damned old pasture cowboy but............................................ don't sit there and tell me that me that I need to pony up $$$ for 50K DNA work to make my EPD's more accurate 2 years ago at KC and then tell me this year accuracy don't mean a damn thing and I may have to go to 77K. Is that the message from this years convention? amongst things, revelations of inpending blind alleys and proposed solutions based of mice and men and their canine friends blessed are the simplebecause I don't need a DNA test to tell me a open cow has fertilty issues.
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Deleted
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Post by Deleted on Nov 3, 2013 9:31:51 GMT -6
Is that the message from this years convention? amongst things, revelations of inpending blind alleys and proposed solutions based of mice and men and their canine friends blessed are the simplebecause I don't need a DNA test to tell me a open cow has fertilty issues. Back to the basics is always a good place to go.
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Post by bookcliff on Nov 3, 2013 10:02:37 GMT -6
Bear with me for a moment and let us assume that EPD'S work. 1) Would breeders that truely had higher numbers receive more buyers? 2) Do average breeders suffer because customers don't know what EPD'S to select considering their management and enviorment? 3) Working correctly, what numbers would you strive to keep in your herd? 4) Are you committed to a bloodline regardless if EPD'S did or did not work? #1 higher is not always better. when is enough enough for growth or for that matter milk but it's damn tough to sell averge growth numbers when in fact in a lot of cases that is exactly what is needed when you talk to them about their goals and direction #2 by average, I assume you mean the segment that sell range bulls. but that being said my answere is see the above. #3 while everyone else will an answere based on thier customer base and breeding program (and the 2 should go together because if they don't you need to rethink what your doing here) here is ours as far as what oru customers are looking for BW 2ish or lower, WW and YW don't really care as long as the bulls are over 6 at weaning and over 1,000 (preferably 1050-1200)at yrl in the low 5 to low 6 frame range without being fat and no creep, in otherwords cows run the same as them. the hadful that do look at EPD's and put selection pressure on it lool for ww upper 30's to upper 40's, yw upper 60's to teh 80's. don't lkie huge numbers since most of em don't wnat bigger cows. milk don't want extremes either way, carcass a farely larege group of my custmoers retain ownership and as such most of em would rather look at my reams of data since we have feed em out for 18 yeara and ultrasounded for 20 so they put more faith into the data than the EPD's, the ones that do put more faith into the EPD require both to be positive. none of em look at the indexes, have yet to have one who looked at M&G. I guess for me I like to see scrotal at or over 1.0, i feel this is about the only EPD that hasn't been bastardized and still works. #4 I personallly think EPD's as a whole are a bastardized COS anymore. conseqeuntly, I have gone back to the old ways, pedigrees and data and EPD's play very little role in our process except for looking out for extremes that are either already wrecks. so to answer your question pedigree and what is know about it and tha actual data that had came form it holds way more punch to me that the EPD it carries.
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Post by George on Nov 3, 2013 10:02:52 GMT -6
Bear with me for a moment and let us assume that EPD'S work. 1) Would breeders that truely had higher numbers receive more buyers? 2) Do average breeders suffer because customers don't know what EPD'S to select considering their management and enviorment? 3) Working correctly, what numbers would you strive to keep in your herd? 4) Are you committed to a bloodline regardless if EPD'S did or did not work? EPDs do work. They just don't work the way a lot of folks use them. If a person wants to compare two highly proven sires, like Harland to 3027 OR Keynote to Online they provide a pretty reliable way to make those comparisons. However, EPDs are an unreliable tool for comparing the rest of the Hereford population, especially those whose accuracy levels on their EPDs fall below that .6 level. The academic wants to say that 68% of the population have accurate EPDs to one standard deviation, which can still be a pretty broad field when you start looking at how far the numbers can vary. And he adds that they are really more accurate than that - and the math proves it. But there is still that roughly one third of the population whose EPDs will eventually fall outside that "one standard deviation". So, that yearling bull that you looked at and chose because his BW EPD was a +2 might really be a +4 and that yearling bull that you really liked but passed on because his BW EPD was above breed average at +4 might really be a +2. Folks, you just can't split hairs with any confidence when the EPD accuracy levels are as low as they are in unproven bulls (and cows and heifers). Of all the statements made in this thread, Doug Thorson made the best. The right way to use EPDs in choosing young bulls is to keep your sale catalog sealed and in your pocket, go look at the pen of bulls and make your choices, THEN look at their EPDs (and pedigree/parents/actual data) to see if there is anything there that raises a red flag. But that requires someone actually knowing something about the visual signs of functional type.
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Post by bookcliff on Nov 3, 2013 10:07:43 GMT -6
George,
you summed it all up. couldn't agree with you more.
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Deleted
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Post by Deleted on Nov 3, 2013 11:01:08 GMT -6
Lol. My father used to joke "the best use of a sale catalog was as something to sit on so the bleachers don't get your jeans dirty."
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Deleted
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Post by Deleted on Nov 3, 2013 18:24:09 GMT -6
I am just a damned old pasture cowboy but............................................ don't sit there and tell me that me that I need to pony up $$$ for 50K DNA work to make my EPD's more accurate 2 years ago at KC and then tell me this year accuracy don't mean a damn thing and I may have to go to 77K. As we have discussed before TK, 90% of the people we sell cattle to don't really care about any of this "fancy stuff" or EPD's. They just want cattle that will work, are problem free, and the reputation that stands behind them.those are exactly my goals with this whole deal. i wouldn't even be doing it if i didn't have confidence in their ability to work and be problem free (not that i haven't been wrong before or won't eve be again) - the reputation thing i got a long ways to go on... i don't know about you guys but i have it in my head i can accomplish that or atleast try without having any involvement with the association. the only reason i haven't just quit the registering deal is solely because i think if i were to become somehow not capable of doing the work here and the cows had to go - i think they would be worth more with papers and epd's whether i agree with it or not. maybe im wrong. id be curious if there are any folks on here that have just quit the aha involvement and kept on. i'd just do the pedigree thing but id still be paying the association plus its been a long time tradition. i don't know, but im torn over it... and every time i write a check to the aha i wonder why im doing it still.
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Post by timbernt on Nov 3, 2013 20:38:24 GMT -6
If you quit our Herefords are one step closer to being another hobby breed. You would always have an empty place in your psyche. Your herd would drop to the value of commercial cows. You would not be able to converse with other Hereford breeders on an equal footing. You would not have the same interest in the new crop of calves on the way. Yeah, we have all wondered why we do this. Probably a lot like other addictions. All the same, you will be glad you stayed with the registered Herefords.
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Deleted
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Post by Deleted on Nov 4, 2013 9:59:17 GMT -6
As we have discussed before TK, 90% of the people we sell cattle to don't really care about any of this "fancy stuff" or EPD's. They just want cattle that will work, are problem free, and the reputation that stands behind them. Sounds like a good policy to me. I think too often people try and out-smart themselves. In my experiences with cattle, education, and coaching, those who stick to the basics will have steady success over the long haul. Those who go with the gimmicks and gadgets may have a brief "flash in the pan", but tend to fade away after several years. Unless the train wreck happens first.
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Post by strojanherefords on Nov 4, 2013 12:29:15 GMT -6
As we have discussed before TK, 90% of the people we sell cattle to don't really care about any of this "fancy stuff" or EPD's. They just want cattle that will work, are problem free, and the reputation that stands behind them.those are exactly my goals with this whole deal. i wouldn't even be doing it if i didn't have confidence in their ability to work and be problem free (not that i haven't been wrong before or won't eve be again) - the reputation thing i got a long ways to go on... i don't know about you guys but i have it in my head i can accomplish that or atleast try without having any involvement with the association. the only reason i haven't just quit the registering deal is solely because i think if i were to become somehow not capable of doing the work here and the cows had to go - i think they would be worth more with papers and epd's whether i agree with it or not. maybe im wrong. id be curious if there are any folks on here that have just quit the aha involvement and kept on. i'd just do the pedigree thing but id still be paying the association plus its been a long time tradition. i don't know, but im torn over it... and every time i write a check to the aha i wonder why im doing it still. Unfortunately, the association does not represent people like us. It still irks me that Hereford World did not run Ken Ochs obituary. But without papers our cattle are just mutts.
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