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I've been an ardent 1/3er from the start or this thread. But....I can see a sort of scenario or way of looking at this where you could conceive and 50% result as legitimate.
If we view this as we are witnessing an unfolding event where the wife could have said 'sorry no, they are both girls' but it just didn't play out that way the 1/3 result is obviously the correct one.
If we are however witnessing an engineered event where the wife will always answer yes so the final question can be asked where you ensure one dog is male when you set it up then the 50% result is the correct one.
The first scenario is to my mind at least the correct way to approach the problem. The second one is a bit daft. But I do now acknowledge it is a way of looking at the problem.
where you ensure one dog is male when you set it up then the 50% result is the correct one.
Only if you do that by specially selecting the initial population to give an equal amount of mixed-sex and all-male pairs.
But there is no suggestion of any shenanigans like that in the question.
Changed the question! Thats cheating.
you can check this yourself by tossing a pair of coins...
You're late - the other tossers are about 3 pages back!
😀
What’s your favourite Revel?
The peanut one. This is mainly due to the fact that an old school friend is allergic to them and when drunk would play Revel roulette. There was a 50% chance that 1/3 of the time he’d have breathing difficulties.
When are we starting on the original, unedited question then? Maybe that should be a separate thread...
The original is buried way back with a link to the formula but the 52% don't trust experts.
A shopkeeper says she has two new baby beagles to show you, but she doesn't know whether they're both male, both female, or one of each. You tell her that you want only a male, and she telephones the fellow who's giving them a bath. “Is at least one a male?” she asks him. She receives a reply. “Yes!” she informs you with a smile. What is the probability that the other one is a male?
I tend to agree with Cougar that the wording in that one is poorer as it doesn’t make it as clear which probability they are actually asking for.
For me it's easier to understand. 🤨
In changing the wording, the OP changed the question. The only way these riddles "trick" you into getting them wrong is the very careful wording. Changing the wording in this case makes the "right" solution wrong.
This riddle has been passed around the internet a lot and moved further and further from the original each time. The most glaring and easily understandable change is from "what are the chances of the other one being male" to "what are the chances of the other one also being male"
It's likethee difference between what are the chances of ending up with 6 numbers in a lottery draw vs. the chances of ending up with your 6 numbers in a lottery draw.
In changing the wording, the OP changed the question.
It doesn't it just seems to confuse people but so does the original.
12 pages!! You guys are my ****ing heros!
Mathematician thinking this is a mathematical calculations riddle and making mistaken assumptions shock!!!
Which assumptions are mistaken?
That the population of this board is exclusively mathematicians? There could well be a significant number of Eng Lit students who study the story and do a different type of analysis, or 'people' people who apply Real Life experiences to their critical thinking....for example.
Lol: I'm seeing adverts from the Alzheimer's Association now...is that a co-incidence??
I'm always impressed by how much people can argue over the Monty Hall problem.
It's fairly simple to test it yourself if you don't believe the 'mathematical' solution.
I’m always impressed by how much people can argue over the Monty Hall problem.
I can see how people miss it. They concentrate on there just being 2 doors forgetting what information they have and can work out.
Argh! Why do I keep looking at this thread!
There could well be a significant number of Eng Lit students who study the story and do a different type of analysis, or ‘people’ people who apply Real Life experiences to their critical thinking….for example.
It’s a problem rooted in mathematics, it’s like saying we’ll agree to disagree about the answer to 1+2, there’s no ‘real life experience’ angle to it.
The most glaring and easily understandable change is from “what are the chances of the other one being male” to “what are the chances of the other one also being male”
But as far as I can see, neither Cougar’s OP text or the original stated here use that “also” phrase at all.
Cougar’s said: “What is the chance there are two boys?”
And this one said “What is the probability that the other one is a male?”
So are you complaining about a question phrasing that wasn’t put to you here on the grounds that it was stated badly elsewhere on the Internet??
Changing the wording in this case makes the “right” solution wrong.
The right answer in both of our cases as stated here is 1 in 3 or 0.33333333...
Wow. Just wow! Anyone who is still arguing against 1/3 is beyond hope. One page 1 sockpuppet did not just explain why it was 1/3, he essentially provided a mathematical proof - using the method of exhaustion. There is no further debate to be had. It is as definitely 1/3, as anything else you hold to be true.
Mathematician thinking this is a mathematical calculations riddle and making mistaken assumptions shock!!!
This is an English language riddle and understanding the very carefully crafted wording is the key.
(25+ year as a business analyst spent trying to get developers to do what the business needs them to do, not what developers assumes needs doing)
You maybe should have thought twice about posting this. It does not paint business analysts in a good light!
Speaking as a developer of 25+ years, it paints Business Analysts in exactly the light I expect. 😂
Maybe leave the number stuff to the engineers?
boys != male puppies
FFS, 12 pages. Very impressed.
12 pages? Good grief. Statistics is a well defined and exact discipline resting on hundreds of years of work. It’s not a matter of opinion!
What's that old quote Moly? Something something damned lies and statistics?
Statistics can say exactly what you want them to depending on how you select your data, no wonder this is a 12 pager! If you wanted it to be concise you would use facts instead 😉
Evening once more.
Interesting that all the 1/3ers have ignored the point I made about how you use the new information, with the exception of convert who is nearly there but too entrenched to admit he is wrong even though he might understand it.
This isn't a maths problem, the maths is simple. It's a philosophical problem about how you use information.
If you check the sex of one dog, and then check the sex of the other, then 1/3 is the correct answer.
Unfortunately, this does not describe the problem.
One dog is male, one dog is either, and it doesn't matter which one is which.
It is interesting to see how the different "personality types" manage or fail to deal with this idea, though I am surprised so many are struggling with (or plain ignoring) it. 🙂
depending on how you select your data
Getting closer!
As an example of a glaring and easily understood nature, which demonstrates what happens when you make seemingly inconsequential changes without grasping that they change the fundamental underlying assumptions of the problem. It isn't about math or stats. It is logic and language. You can put whatever numbers you like into a spreadsheet and prove your answer but if you've read the question wrong it won't help in the least.
@sbob: I didn’t ignore it. I tried creating a new model from the position of knowing that it is not a female-female pair, as you suggested, and I got the same 1/3 result.
You also said try calling them Ishmael and Leslie. I responded to that but you have cunningly ignored it.
I wonder what the overlap is between people that think it is 50:50 and people that think the plane on the conveyor can’t fly?
If you check the sex of one dog, and then check the sex of the other, then 1/3 is the correct answer.
Getting closer!
It isn’t about math or stats. It is logic and language.
Okay, using logic, list the possible gender combinations of Dog A and Dog B, given that you know they are not both female?
You also said try calling them Ishmael and Leslie
That was more an attempt at humour and probably just confused matters. Ishmael and Leslie are just synonyms for the dog that is male and the dog that is either. It does not matter which is which.
I tried creating a new model
And you failed because you are still dissecting the problem into two (or three!) parts that happen one after the other. This is not the case.
We know one of the dogs is male.
We know the other dog is either.
It doesn't matter which is which, it changes nothing.
This is another case of not seeing the wood for the trees.
Okay, using logic, list the possible gender combinations of Dog A and Dog B, given that you know they are not both female?
Dog A or B is male.
The other is male or female.
The word you are incorrectly using in your logic is "if".
There is no "if", there is only "is".
Okay, using logic, list the possible gender combinations of Dog A and Dog B, given that you know they are not both female?
Is that what the question is asking, or is it asking what is the probability of 2 out of two dogs being male given that 1 out of the 2 dogs is male?
That was more an attempt at humour and probably just confused matters. Ishmael and Leslie are just synonyms for the dog that is male and the dog that is either. It does not matter which is which.
Except it very much does. As I explained with Ishmael and Leslie. All you know is that there is at least one male. So the possibilities are:
1) Ismael is male and Leslie is male
2) Ismael is male and Leslie is female
3) Ismael is female and Leslie is male
What you are trying to do is say “Ishmael is definitely the male dog so we can discount scenario 3”.
That is using knowledge you do not have.
And you failed because you are still dissecting the problem into two (or three!) parts that happen one after the other.
Nope. Start from the point where you have a dog in each hand and I tell you they are not both girls. What are the possibilities? List them.
No dissection or steps or temporal aspect required. Just tell me the possible combinations.
The word you are incorrectly using in your logic is “if”.
You have literally just quoted me not using the word “if” then told me off for using the word “if”.
Stop using the word “flamingo” please. That is where you are going wrong. 🤪
Is that what the question is asking, or is it asking what is the probability of 2 out of two dogs being male given that 1 out of the 2 dogs is male?
It is the same answer.
List all the combinations where at least one dog is male. There are three. Only one of those combinations is male-male.
(Going to bed. Have fun)
You are not grasping the subtle but important difference. If the question is phrased in such a way that it forces you to address the dogs as a pair (the pair being a singular unit with the characteristics of MF, MM, FM and FF) then the punnett square solution you are fixated on is appropriate. If the question is phrased so that it simply asks about 2 individual dogs, each as it's own singular unit having only one possible characteristic of M or F then your approach doesn't work.
The original wording of the problem does this. The changed wording does not.
Start from the point where you have a dog in each hand
That point does not exist.
You have literally just quoted me not using the word “if” then told me off for using the word “if”.
Sorry, I thought in relation to logic it was obvious.
What you have been saying all along is that if the dog in your left hand is male then the dog in your right is male or female, and if the dog in your left is female then the dog in your right is male which gives you your three options.
This is where you have been going wrong. There is no if, no one then the other because as soon as you consider one it changes the odds of the other which is not dictated in the original conundrum.
There are two dogs, one is male, the other is male or female.
Inside Sbob's head.
Inside STW:
Why is it that the homepage shows this thread at 12 pages, but this is page 13?
It's a forum feature.
The most glaring and easily understandable change is from “what are the chances of the other one being male” to “what are the chances of the other one also being male”
This what I said pages and pages ago. The explanation in the link adds the word also which utterly changes the question. Its badly word, or very well worded, depending on what its trying to achieve.