Probability Fact
@ProbFact
Followers
146K
Following
70
Media
446
Statuses
8K
Daily tweets on probability from @JohnDCook.
Joined November 2009
No, there’s a 50-50 chance two people share SOME birthday, not a PARTICULAR birthday.
28
81
2K
Male heights have a normal distribution centered at 5' 10" with a standard deviation of 3 inches. The probability of an 8 foot tall man is on the order of 1 in 1,000,000,000,000,000,000. And yet there are men taller than 8'. The record is 8' 11".
36
120
889
"Probability is the intersection of the most rigorous mathematics and the messiest of life." -- Nassim Taleb.
14
456
747
Discrete probability is conceptually easier than continuous probability because counting is easier than measure theory.
9
49
740
A random variable is a measurable function on a probability space.
7
66
753
'Probabilistic' comes from Latin. 'Stochastic' comes from Greek.
6
84
701
Conditional probability is subtle. All probability is conditional. Therefore all probability is subtle.
12
113
504
Next in the review queue: Bayesian Probability for Babies
12
124
464
'There are only five probabilities the average human can handle: 99 percent, one percent, 100 percent, zero, and 50-50. That’s it.” — Richard Thaler.
13
66
434
'Probabilistic' comes from Latin. 'Stochastic' comes from Greek.
5
37
421
Random phenomena are not obligated to follow one of the few dozen distributions that humans have given names to.
1
115
407
'Probabilistic' comes from Latin. 'Stochastic' comes from Greek.
2
47
405
'Probabilistic' comes from Latin. 'Stochastic' comes from Greek.
6
52
375
If P(A | B) > P(A) then P(B | A) > P(B). If B makes A more likely then A makes B more likely.
3
38
378
'Probabilistic' comes from Latin. 'Stochastic' comes from Greek.
1
57
370
If P(A | B) > P(A) then P(B | A) > P(B). If B makes A more likely then A makes B more likely.
2
32
368
The probability that two random integers are relatively prime is 6/π^2.
8
89
361
'Probabilistic' comes from Latin. 'Stochastic' comes from Greek.
2
46
350
'Probabilistic' comes from Latin. 'Stochastic' comes from Greek.
2
53
347
Discrete probability is conceptually easier than continuous probability because counting is easier than measure theory.
10
23
339
Discrete probability is conceptually easier than continuous probability because counting is easier than measure theory.
4
22
356
If P(A | B) > P(A) then P(B | A) > P(B). If B makes A more likely then A makes B more likely.
5
38
340
'Monte Carlo is an extremely bad method; it should only be used when all alternative methods are worse.' -- Alan Sokal.
12
34
328
Uncorrelated random variables are not necessarily independent.
3
44
331
Uncorrelated random variables are not necessarily independent.
5
42
329
'Probabilistic' comes from Latin. 'Stochastic' comes from Greek.
2
61
312
'Monte Carlo is an extremely bad method; it should only be used when all alternative methods are worse.' -- Alan Sokal.
4
18
328
'There are only five probabilities the average human can handle: 99 percent, one percent, 100 percent, zero, and 50-50. That’s it.” — Richard Thaler.
8
37
326
Discrete probability is conceptually easier than continuous probability because counting is easier than measure theory.
7
32
295
If P(A | B) > P(A) then P(B | A) > P(B). If B makes A more likely then A makes B more likely.
5
66
301
If P(A | B) > P(A) then P(B | A) > P(B). If B makes A more likely then A makes B more likely.
8
63
295
'Monte Carlo is an extremely bad method; it should only be used when all alternative methods are worse.' -- Alan Sokal.
17
56
290
If I flip a coin, look at the result, but don’t show you, its state is random for you but not for me. Probability describes knowledge.
4
188
292
Discrete probability is conceptually easier than continuous probability because counting is easier than measure theory.
8
50
284
'. the theory of probabilities is at bottom only common sense reduced to calculus.' -- Pierre-Simon Laplace.
4
40
284
If P(A | B) > P(A) then P(B | A) > P(B). If B makes A more likely then A makes B more likely.
2
41
277
A random variable is a measurable function on a probability space.
3
31
275
One way to think of the Markov assumption: The future is independent of the past, given the present.
2
91
266
Markov assumption: The future is independent of the past, given the present.
5
80
272
If A makes B more likely, B makes A more likely. P(B | A) > P(B) => P(A | B) > P(A).
2
53
264
Information is quantified in terms of surprise. If everything in a message is expected, then it contains no information, no matter how long it is. #informationtheory.
6
84
266
If P(A | B) > P(A) then P(B | A) > P(B). If B makes A more likely then A makes B more likely.
6
68
256
“It doesn’t matter that you’ve had 10 girls in a row. The chances that the next child is a boy are 50-50.”. Not necessarily. 🧵.
16
34
262
If P(A | B) > P(A) then P(B | A) > P(B). If B makes A more likely then A makes B more likely.
4
24
263
Uncorrelated random variables are not necessarily independent.
6
41
254
'There are only five probabilities the average human can handle: 99 percent, one percent, 100 percent, zero, and 50-50. That’s it.” — Richard Thaler.
9
37
261
Uncorrelated random variables are not necessarily independent.
5
32
253
If P(A | B) > P(A) then P(B | A) > P(B). If B makes A more likely then A makes B more likely.
6
42
254
“There areonly five probabilities the average human can handle: 99 percent, one percent, 100 percent, zero, and 50-50. That’s it.” — Richard Thaler.
4
52
246
“A thing appears random only through the incompleteness of our knowledge.” -- Spinoza.
10
34
252
Uncorrelated random variables are not necessarily independent.
3
28
244
'There are only five probabilities the average human can handle: 99 percent, one percent, 100 percent, zero, and 50-50. That’s it.” — Richard Thaler.
12
42
242
“In no other branch of mathematics is it so easy for experts to blunder as in probability theory.” — Martin Gardner.
8
18
247
A normal random variable is within two standard deviations of its mean about 95% of the time.
4
26
233
'Probabilistic' comes from Latin. 'Stochastic' comes from Greek.
1
62
237
OH: "Not everything is Pareto distributed, but 80% of it is.".
2
155
226