TRUE..the repairman was looking to see if there were males in the household or someone else who might know he was gouging you when he did the repairs and billed you. i know LOTS of trades repair companies (especially plumbers and heater/AC) that permit their installers to keep half of the take. their crooked tradesmen will look around to gauge the ability of the customer to call BS on unnecessary or bogus repairs...especially on women who are unlikely to know if there even is such a thing as a conibbler pin or a fragistat. years ago my wife got a bid for $750 for new brake pads on a small car. when i called the guy to ask if that included the rears and new rotors and bearing he said no...JUST PADS, front only...no fluid bleed, no bearing regrease, not even a rotor resurfacing. i told him he should be ashamed of himself as i had a bid from the local legit repair shop for $130 including surfacing, repair persons are incentivized to overcharge but are smart enough to do it so they don't get caught
As someone who uses Bayesian systems professionally, in daily life thinking, and also to show why other people's arguments don't land, I have to say that this is a fantastic video. It very clearly illustrates to the layperson why Bayes is what is and what the messages are. I will be sharing this with others.
Let me guess, you're one of those geniuses that predicted that there was no way for Donald Trump to win? because after all, Hillary got the women vote, the latino vote...lol
I've often seen Bayesian analysis in the title of academic papers, and this explained the basic principle. But instead of offering five very similar examples, perhaps she could have moved on to some more advanced applications in scientific inquiry and statistics.
_"As someone who uses Bayesian systems professionally"_ It's funny, because for people with any amount of intelligence these kinds of methods would just be completely intuitive, obvious or logical when working out decisions, it's incredibly basic mathematics. But then I guess I should never be surprised by how low the bar can be.
+jamma246 If you think this sort of thinking is intuitive, then you might want to check out LessWrong.com so you can see how deep the rabbit hole goes. Fallacious and biased reasoning is the norm in 98% of the population. Most humans are extremely weak at rationality by default. This makes the world a rather frustrating place.
This is really well done and appropriate for understanding the intuition of Bayesian probabilistic thinking. I teach this law to my Math students in grade 12 and I will show this video to them.
Bayes' Rule is an important component of critical thinking. The ability to think critically is a skill that needs to be learned. The challenge is that common sense and intuition are often very wrong, and there's no trivial way for knowing when. It's on a case-by-case basis, and all those cases are about patterns that need to be recognized and examined.
_sees repairman checking out my bedroom_ _slams him against the wall_ "8% chance you're gonna rob the place, huh punk?" "but sir, I'm here to repair your bed" "Bayes would disagree .... get out before I call the police"
Thank you for this video. Your examples are super enlightening and I feel like you've communicated the idea of prior and posterior probability better than my own theory of probability/statistics classes. One thing I wanted to mention, though, is that I think we need to change the way we think about the term "placebo" (and I'm very guilty of this myself). You say that the placebo effect could be evidence that meditation is fake, but I'd argue that the placebo effect can also be evidence that meditation does work. If Bob expects meditation to work, and it results in him being happier, then the mechanism "behind" meditation ultimately doesn't matter because it works for him regardless. The same can be said for placebos in double blind medical trials. If a person sees benefit from taking a placebo, unaware that it's a placebo, that doesn't negate the fact that they saw benefit from it. Sure, the placebo isn't "doing" anything, and there are definitely other factors at play that could be helping, but our brains are also weird and easy to fool. Anxiety is strongly linked with gastrointestinal health, and psychosomatic symptoms are still symptoms. Just some food for thought!
I've been struggling to "get" bayesian stats for a couple of years, sorry to say, because even in my technical work (biomedical informatics) I need visual representations of abstract relationships to help me think through problems. So your visual aids were extremely helpful to me. They took a rather wobbly abstract concept of priors and offloaded them to a visual concrete representation to reduce cognitive load. Thanks so much and I've subscribed to see what else I can learn!
To me, it's a cognitive load even after visual representations. One is either numerically/scientifically predisposed or isn't. I don't think you can force yourself to become adept at something you're not naturally adept at.
This is the kind of woman the media should be giving exposure to, and not the Kardashians of the world, if we start valuing the pursuit of knowledge, with acknowledgment, money, fame, etc the society will be a better place for all of us.
Think more the hardest way as wise as how I'm honest to myself, with every details of how I spend my precious seconds of every minutes of every hours.... Vs Think more the hardest way even when I was supposed to be happy in a framely set-up man-made time-line schedule
I like her thinking. Reminds me of little Johnny in class. The female teacher hides a fruit she gets out of a bag behind her back and says, “Class, I am holding a fruit behind my back. It’s long and it’s yellow. Who can guess what it is”? Little Susie holds up her hand, then the teacher calls upon her, and she says, “it’s a squash”. The teacher displays the hidden fruit and says, “No Susie, it’s a banana. But I like the way you’re thinking”. The teacher then secrets another fruit from her bag, hides it behind her back, and says to the class, “I am holding a fruit behind my back. It’s round and it’s red. Who can guess what it is”? Little Mikey holds up his hand. The teacher calls upon him and he says, “It’s a cherry”. The teacher then displays the hidden fruit and says, “No Mikey it’s an apple. But I like the way you’re thinking”. Little Johnny then asks if he can hide something. The teacher thinks for a second and says yes. So Little Johnny puts one hand in his pocket and says, “ Teacher, I’m holding something in my hand. It’s round and it’s hard. Can you guess what it is”? The teacher blushes bright red, then becomes enraged, and says “Little Johnny, we will not have any such vulgarity in my class. Go to the principal’s office right now.” Little Johnny then displays what he was holding to the class and says, “Teacher, it’s a quarter. But I like the way you’re thinking.”
Think more as wise as possible to not be discourage when everyone says bad things on my back Vs Think more as wise as possible to learn how to finish my own scheduled duty in a day and bother not with everybody else's businesses
I’m not sure the goal of meditation is to make you happier per se. I used to think thinking harder about something would lead me to the answer, then I learned how to meditate (which is not thinking). The meditation allowed me to approach the original question fresh and unencumbered. Secondly, there are different levels of ability in meditation, it is not binary. I am very much a beginner, but it helps tremendously in many areas, including problem solving, and even insomnia. Highly recommended.
Think more when I'm wise enough to stick with treasure.... Vs Think more it doesn't mean I can be easily fool by those who die-hardly tried to teach me morally lesson
Hi, Julia. I just stumbled on your channel. Thanks for this! And an observation: I'm struck by how similar Bayes's style of thinking is to David Hume's. I imagine there's some already well known connection here.
Think more the hardest way to fool not by alternative secrets of the miraculous appearers Vs Think more as wise as how I didn't appreciate the everything comes in one tactics
There’s also something called human nature, and if you understand how the brain works, you can infer easily how meditation can improve someone’s life. So even though Bayesian think can make you kind of a more pragmatic person, it still doesn’t replace domain knowledge and common sense.
Think more the hardest way with some common backup tools available in the market such as •Backup Home, •Auto back-up, •Taskzip, •Backup Platinum etc... Vs Think more the hardest way as how several methods for data backup can be included such as Full Backup, Incremental Backup, Online Backup, Drive Imaging etc
I've had to become an expert in this field. You have to be careful about what you want to believe versus what is. For example right now I'm trying to figure out if my feed is constructed or generated. Conspiracies are tough.
Think more when I'm wise enough to not let those outsmarters chickenly tricking me... Vs Think more especially when I was forced to shut my mouth while I had many things to say
Think more the Hardest way as how the many sources have claimed that Boris Inster's andRKO's Stranger on the third floor (1940) was the first full-featured film noir... Vs Think more the Hardest way as how Orson Welles' films have significant noir features such as in his expressionalistically-filmed Citizen Kane (1941) with subjective camera angles, dark shadowing, deep focus, and low angled shots from talented cinematographer Gregg Toland
Think more the Hardest way as the second factor of how the advertisement should not only catch the attention of the people but should also maintain the interest of the public Vs Think more the Hardest way as the third factor of how the advertisement should be able to stimulate the desire of the public so that they consider buying that particular product
Think more the hardest way no matter what, although how much time I was framed to struggle with, for the deceivers' techniques virtually for more than 1/4 portion of a day Vs Think more just as wise as how I'm still proud of your body to me though how much I was being pulled to like what that distracted my focus, especially when everyone thinks they can easily ruin my weaknesses...
Think more the quickest intuitively way as S is for *Step Out Of Comfort Zone* again Vs Think more the quickest intuitively way as S is for *Score While We Play Hard* again
So "Bayesian" thinking is essentially "contextual" thinking, to put it in a simpler (non-mathematical) form. The context of any state of affairs is crucial to its understanding. So then the issue becomes, how far do you go in contextualization? But I guess that's really beyond the scope of mathematics.
Think more the wisest way *at the same time, no matter how simple a message may be, people will complicate it* Vs Think more the wisest way *As communicators, we cannot forget or ignore those people who expected 'significant' messages to be complicated*
Think more the quickest Intuitively way as *How much of that time is spend on a) Talking b) Listening* Vs Think more the quickest Intuitively way as how we can *List at least 3 media we regularly use as a Communicator*
Think more the hardest way to not be fool by how others think and how they elaborated through actions ... Vs Think more the hardest way why Tea with milk and raw red tea are introduced as light refreshments
Think more the hardest way as how Travelogue films were the most popular of the films in those times Vs Think more the hardest way as how a film called "South" highlighted about the imperial Trans-Antartic Expedition that was released in 1919
Think more the hardest way as wise as how *Sometimes certain special characters must be included as a part of string comstant* Vs Think more the hardest way as how *The compiler automatically places a null character (\0) at the end of every string constant*
@@dactorwatson4313 i guess that aint a bad thing. it's just a pity that common brain usage needs to be masked as something fancy. ah well, seems to happen a fair amount....
Hypothetically. If the odds are 1 to 99 to be found not guilty after a federal criminal trial and if the odds are 1 to 100,000 for two people to die accidentally in a few days, then who killed the owner of the SV Bayesian?
Think more as wise as possible with one goal of why I leave home and headed to 30+ KM destination place today... Vs Think more yet fool not by Church stage flex, but as wise as hard labouring excavating construction engine workers in the road even on Sunday
Think more the Hardest way as how a sound that is naturally present in the atmosphere sorounding the visual image and is recorded simultaneously.. Vs Think more the Hardest way as how *Ambience"sound was referred to as 'noise' and speech and music were given more attention
Think more the quickest intuitively way as H is for *Hyper Text Markup Language* Vs Think more the quickest intuitively way as H is for *Hyper Text Transfer Protocol* again
Think more just as wise as one reason that I am afraid to leave you, even I am angry at you repeatedly Vs Think more just as wise as how I didn't wanted to make you feel down just because of me
Its even easier to make an extreme example, so all the hundred students only one is a math major who is shy versus 15% of the business students are shy which are 99 of them. so the chance that’s Tom being a math major is definitely very low even his shy. So the quantity ratio play a very big role here.
Think more the hardest way as how a pile of *Grasshopper* looks like when we cooked them with simple method by attached them in proper arrange on a bamboo piece Vs Think more as the gold color appearance when they are perfect for having them
Think more the hardest way as why the Director is always the final authority on the set but everyone needs to be talking and feel they are part of the process... Vs Think more the Hardest way with why good actors try to become their character which can put them in the state of extreme emotional vulnerability.
My only comment on the topic is that we should be really careful to include all relevant evidence and to ensure we are seeking out more evidence. For low-risk items, like where to go on vacation, that’s not needed. But for single-game life/death scenarios it’s helpful to gain more information rather than relying on the variables you currently have.
Think more the Hardest way as how we should expect that our material might be as long as, and possibly longer than the original when writing for poper Paraphrase.. Vs Think more the Hardest way as why Avoid Plagiarism is a must when writing a proper Paraphrase
yeah in America there's 10M millioniares. That's 3.33% of the population. If you save your money not becoming a millionaire is impossible unless you are 50 yrsold, or have an IQ below ~90ish probably
Think like me who doesn't fall in love to you, but who never allow you to be in love with anybody... Vs Think like I still sense some emotional gamblers trying to snatching you from me
Repairman snooping around for the circuit breaker: Appliance repairmen sometimes have this weird preoccupation with turning off the electricity to an appliance before they work on it. 220 volts can really ruin your day.
In the UK at least, by law there has to be a circuit breaker within reach of the stove. In the US it will be split phase, so pretty hard to get the full 220v.
I've done a lot of repair work, and I know what's it's like to be in the category: "looks like he's going to rob you but really he's just doing his job." Let me tell you - every place is built differently, and you should always keep your eyes open.. One time I found a gas line going into a bedroom and not even capped off. The place would have filled up with explosives at the turn of a knob, well if not for my "snooping about" that is. But it's also part of the job description to not freak people out. I just said, "I need to look around a bit to make sure I know where all the gas lines are going."
That girl did not provide adequate background on stove repair. Like, old house, gas or electic stove. Why is this critical information? A good repair-man/woman, would look around to not only fix the point but also all connected to that point. Also, it would be so easy to inquire, why are you looking into bedroom/s? She phrases it snooping, which is secretly done, which did not seem to the situation/
As a repairman also, I'll throw in my 2 cents worth. When you enter a house to do repairs you should always examine your surroundings to identify any potential exit points or hidden dangers such as friendly dogs that don't bite (been bitten twice).
Brew Sauce+ I've done a lot of electrical repair work, and it becomes second nature when entering an unfamiliar place to glance around looking for potential problems, to a point where one may not even be aware of it. And btw, I've spotted many problems -- shock and/or fire hazards -- that the homeowner was oblivious to. It is the responsibility of the electrician to spot these hazards, point them out, and recommend (even insist) appropriate remedies. I imagine it's the same for someone coming to repair your gas range (assuming it is a gas range). He would want to know if there any other gas appliances in the house, any lines/valves/couplings that might be problem, etc. It would be irresponsible to not ascertain this info.
The trouble with updating beliefs while encountering new evidence today is we can all find evidence to support any belief. It really depends where one looks for said evidence. We all have so many information sources to tap now. So everyone can easily find whatever echo chamber they need, to reinforce whatever belief they hold dear.
Your statement is fully correct. It looks that statistics become more stable if you get more and more data. However the quality of data matters a lot too! And this is also included to the Bayes theory! The simplest example is having two Gaussian distributions, if you put them together, the tighter one will win, i.e. the more uncertain one has little impact. Indeed it is hard to quantify everything, but with the Bayes theory all is combined at least in a consistent way. If you want to get on something, the theory helps you not to loose.
Yes, you have to be honestly self aware to be able to use the principle - ie you have to ask the question "how would the data look in my personal echo chamber if I was wrong" vs "how would the data look in my personal echo chamber if I was right"? And you would honestly have to draw the conclusion that my echo chamber will still only resound the message I already have taken as true, wether my belief is true or not.
I never update my priors. In fact I would have assumed the repairman was wondering where he was gonna lay me out after eating my liver with some fava beans and a nice chianti. Fake repairman is the oldest cannibal trick in the book.
Good. I've "known" Bayes' rule for 50 years but your explanation was the best visual one I've seen. I like the way you apply it to everyday life. Thank you.
Another important clue that Tom is a Math PhD student: He's walking. MBA students travel around campus in golf carts that they stole from the campus maintenance department.
remember your priors, how likely is it that a math PhD has the courage to venture outside of their room and into the savage social environment of the campus
The fact that there's so many comments here along the lines of "wow, this totally changed my perspective on everything" is quite unsettling to be honest.
@@rephaelreyes8552 Yeah that's why mathematicians have all the private jets, super cars, and hundred foot yachts, and they get aaaaalllllllll the bitches. LOL shut the fuck up.
Couldn't help smiling when I head the words 'Berkley' and 'snowflake' in the video. Hard to imagine extremely intelligent people becoming snowflakes. But may be there is no correlation between intelligence and wisdom. Not saying the presenter is a snowflake. But I see a lot of young people take positions that would be considered 'progressive' in their eagerness to 'look' elite among their peers.
+B-Rad that's exactly what I am talking about - Classic elitism. I should have also added that this behavior has to do with conforming with 'views' spread by the progressives elites, so one could look like them. It is implied in my statement, but seems some people need more clarification. Let me guess, you 'think' to care about animals & environment means to not eat them, because you have 'learned' this info from material that you read or watched on T.V or the internet. If you tell me you have a psychological problem to kill and eat another living, breathing thing, I will probably excuse you. But, the loving animals and earth etc is baloney. You just don't realize it is baloney - that's all. If I prove to you that vegetables and plants also perceive pain..... my bad, this has already been proven. (Read about scientist Bose's work from more than a 100 years ago) Will you stop eating food altogether?
Think more as wise with 98 minutes ago since 03:00 PM Vs Think more as wise as how I stopped having evening refreshment tea and lunch at home, yet with a somehow little effort I managed to cut the grasses as I was assigned to
I couldn't help being distracted by that light switch just left of your head, so . . . Bayesian thinking: 1. By your accent, you are probably American filming this in the USA. 2. Common US building code makes the top of the light switch about 4' high. 3. By making a quick judgement call, if you were standing up for this video your height would be about four foot, three inches. 4. By my experience the percent of adult women in the US who are only that tall is less than 1%. 5. I am adjusting my perception of you standing in front of a wall to perceiving you seated in a normal chair talking to a camera on a tripod. Okay, I am subscribing to your channel.
Problem #1: When an accident happens, what is the probability that the accident is caused by a bad driver, given that: 1) 90% of the population has been involved in at least one accident 2) 30% of the population are bad drivers (means 70% are good drivers) 3) 99% of the bad drivers are involved in at least one accident P(Bad Driver) = 0.3 p(Accident|Bad Driver) = probability of a bad driver causing an accident = 0.99 P(Accident) = 0.9 P(Bad Driver|Accident) = probability of an accident caused by a bad driver = 0.99 * 0.3 / 0.9 = 0.33 = 33% When an accident happens, there is only 33% chance that the accident is caused by a bad driver. --------------------------------------------------------------------------------------------------------------------------------------------- Problem #2: Find the chance of having cancer, given that the customer is 65 years old. Facts: (a) 1% of the population have cancer (99% don't have cancer) (b) 0.2% of the population is 65 years old (c) Of those that have cancer, 0.5% of them are 65 years old P(Cancer) = 0.01 P(65 yr old) = 0.002 P(65 yr old | Cancer) = 0.005 P(Cancer | 65 yr old) = What percent of the 65 year old population is likely to have cancer = P (65 yr old | Cancer ) * P (Cancer) / P(65 yr old) = 0.005 * 0.01 /0.002 = 0.025 Only 2.5% of the 65 year old population is likely to have cancer. --------------------------------------------------------------------------------------------------------------------------------------------- Problem #3: Given the following: (a) 1% of the population have breast cancer (99% don't) (b) 80% of the mammograms detect breast cancer (20% don't) (c) 9.6% of the mammograms detect breast cancer when it's not there (90.4% of the tests correctly return a negative result). You have got a positive result.What are the chances that you have breast cancer? P(Breast Cancer|Positive Result) is what we have to find. P(Breast Cancer) = 0.01 P(Positive Result|Breast Cancer) = 0.8 P(Positive Result) = We need to consider both positive and false positive = Positive + False Positive = You have breast cancer and you have been correctly identified as having breast cancer + You don't have breast cancer but have been identified as having breast cancer = 0.01 * 0.8 + 0.99 * 0.096 = 0.10304 P(Breast Cancer|Positive Result) = 0.8 * 0.01 / 0.10304 = 0.0776 So, if you have a positive result, there is only 7.76% that you have breast cancer.
Problem #4: Spam detection (a) 50% of the emails are spam (b) Out of 1000 spam emails, 110 contain the word 'Nigeria' (c) Out of 1000 non spam emails, 48 contain the word 'Nigeria' A message with the word 'Nigeria' arrives in your inbox. What are the chances that this message is spam? P(Spam|Nigeria) is what we have to find. P(Spam) = 0.5 P(Nigeria|Spam) = 0.11 P(Nigeria) = Probability of a message having the word 'Nigeria' = Probability of word 'Nigeria' appearing in a spam email + Probability of 'Nigeria' appearing in an non spam email = 0.11 * 0.5 + 0.048 * 0.5 = 0.079 P(Spam|Nigeria) = P(Nigeria|Spam) * P(Spam) / P(Nigeria) = 0.11 * 0.5 / 0.079 = 0.69620 There is a 69.2% chance that the message containing 'Nigeria' is a spam.
xazzbi Yes, just draw the rectangles as in the video. Instead of Math/Business you have cancer/no cancer, and instead of shy you have "positive result".
P(Cancer) * P(65 yr old | Cancer ) represents the Probability that someone you know nothing about has cancer AND is 65 years old (first you take P(Cancer) since you know nothing about that person and then you multiply P(65 | cancer) since the cancer part is already included in the first probability). Now you have the "pool" of people who are both. But since you know (in the problem) that the relevant portion is 65 years old you have to divide by that probability to include that knowledge. Proof (I know it's not helping to visualize :P): P(Cancer) * P(65 | Cancer) = P(65&Cancer) = P(65) * P(Cancer | 65) P(Cancer | 65) = P(65&Cancer)/P(65) = P(Cancer) * P(65 | Cancer) / P(65)
It should be noted that the conclusion of problem #3 only applies if you randomly test people from the population. If you were prescribed a mammogram to begin with, there are other reasons why your physician suspects you might have cancer, and therefore belong to a population that, even before testing, has a chance of having cancer higher than 1%. Also, is your figure of 9.6% of false positives a real one or did you make it up?
Minor point, but... when it comes to mental health, a consistent placebo effect is better known as a "cure". If something makes someone happier regularly, calling it a placebo effect is kind of meaningless, no?
maybe in the realm of mental health, it could mean that it might seem to be working to cure their mental issues, but is actually only demonstrating short term cures and nothing permanent or in the long term. Depends on what the context and goal is though, I guess.
