MindMap Gallery Probability Theory Course Summary
Summary of teacher Li Yong's probability theory course, including random phenomena and basic concepts, probability space, three problems, random variables and random vectors, etc.
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This is a mind map about plant asexual reproduction, and its main contents include: concept, spore reproduction, vegetative reproduction, tissue culture, and buds. The summary is comprehensive and meticulous, suitable as review materials.
This is a mind map about the reproductive development of animals, and its main contents include: insects, frogs, birds, sexual reproduction, and asexual reproduction. The summary is comprehensive and meticulous, suitable as review materials.
This is a mind map about bacteria, and its main contents include: overview, morphology, types, structure, reproduction, distribution, application, and expansion. The summary is comprehensive and meticulous, suitable as review materials.
This is a mind map about plant asexual reproduction, and its main contents include: concept, spore reproduction, vegetative reproduction, tissue culture, and buds. The summary is comprehensive and meticulous, suitable as review materials.
This is a mind map about the reproductive development of animals, and its main contents include: insects, frogs, birds, sexual reproduction, and asexual reproduction. The summary is comprehensive and meticulous, suitable as review materials.
Probability Theory Course Summary
Random phenomena and basic concepts
random phenomenon definition
basic concept
Sample definition/intersection and union operations/limits of event sequences/intersection and complement duality laws
Event domain (σ algebra)
Definition (3 items) (can be used to prove whether it is an event domain)
σ(A) is the smallest σ algebra containing A
Nature (3 items)
Event domain on real number space—Borel set class
λ-class
Definition (3 items) (can be used to prove that it is a λ-type)
λ(A) is the smallest lambda class containing A
If the set class A is closed for the intersection operation, then λ(A) is closed for the intersection operation
Monotone class theorem: If the set C is closed for intersection operation, then λ(C)=σ(C)
Classical concept
Features
Principles of counting (principles of addition and multiplication)—permutations and combinations
Several common problems: position-occupying problem, lot-drawing problem, ball-touching problem, matching problem (disguised lot-drawing)
Geometric sketch
Features
Several common problems: the intersection of a needle and a straight line, the intersection of a circle and a straight line, the chord length of a circle
probability space
Basic axioms of probability (3 items))
Simple properties of probability (10 items))
Upper and lower continuity; subadditivity; addition theorem
Several probability spaces
Bernoulli probability space
finite probability space
countable probability space
geometric probability space
Conditional Probability
conditional probability space
multiplication formula
total probability formula
Bayesian formula
independence of events
The independence theorem of events and complementary events
Independence of multiple events
Multiple events are independent of each other
Multiple events are independent of each other
independent event family
Multiplication formulas and addition formulas for multiple events that are independent of each other
Connection problem
independence of randomized experiments
Product sample space/measurable rectangle/product event domain/product probability/product probability space
Randomized experiments are independent of each other—experiments are repeated independently
three door problem
Conditional probability solves the three-door problem
Random variables solve the three-door problem
Random variables and random vectors
random variable
Indicative function/inverse image
Operations on random variables (2 items)
theorem
The necessary and sufficient condition for ξ to be a random variable mapping in Ω→R is ξ-1(B)∈F, for any B∈borel set
If ξ is a random variable mapped in Ω→R, then ξ-1(B) is a σ algebra, and ξ-1(B)⊂F
Convergence Theorem of Random Variable Sequences
If the random variable sequence {ξn} converges to ξ, then ξ is a random variable
Borel function f/g
The composite mapping η=f(ξ)/can be extended to multivariate η=g(ξ1, ξ2,…,ξn)
independence of random variables
multiple independent random variables
Independent random variable sequence/independent random variable family
The random variable family of ξ and the random variable η are independent of each other.
Integrate with joint distribution
The necessary and sufficient condition for multiple random variables to be independent is that the joint distribution is equal to the product of the marginal distribution functions or the random vector joint distribution function variables are separable
The necessary and sufficient condition for multiple discrete random variables to be independent of each other is that the joint distribution density is equal to the product of the marginal distribution densities or the random vector joint density variable is separable
The necessary and sufficient condition for multiple continuous random variables to be independent is that the joint distribution density function is equal to the product of the marginal density functions or the joint density function variables are separable
If multiple random variables are independent of each other, they will still be independent of each other under the action of the Borel function.
The structure of a random variable
The definition of simple random variables—ξ(Ω) is a finite set; standard expression
A nonnegative random variable ξ can be consistently approximated by a simple random variable ξn [Non-negative random variable approximation theorem]: If the random variable ξ≥0, Then there is a monoincreasing simple random variable sequence {ξn}, such that when n→∞, ξn=ξ
Any random variable can be approximated by simple random variables "The positive and negative parts of ξ are both non-negative random variables" [Random variable approximation theorem] Assuming that ξ is a real-valued function on Ω, then ξ is a necessary and sufficient condition for a random variable on (Ω, F, P) There is a simple random variable sequence {ξn} such that when n→∞, ξn=ξ
Distributions and distribution functions
Distribution and distribution function formulas/identity mapping/(R, B, Fξ) is a probability space
Distribution uniqueness theorem: distribution and distribution function are mutually uniquely determined
Properties of distribution function F (3 items)
Discrete random variable
Definition/Density Matrix/Probability Support Set/Distribution and Distribution Function Formulas
Binomial distribution B(n,p)—k successes in n experiments b(k;n,p)—the most likely value of binomial distribution
Geometric distribution G(p)—number of first successful occurrences g(k;p)—no memory
Negative binomial distribution Nb(r,p)—the number of successful waits for the rth time f(k;r,p)
Poisson distribution P(λ)—ξt represents the number of particles p(k;λ) arriving in the (0, t] period Random choice invariance of the Poisson distribution/Most likely value of the Poisson distribution
continuous random variable
Definition/Density Matrix/Probability Support Set/Distribution and Distribution Function Formulas
Uniform distribution U(a,b)—distribution function formula
Normal distribution N(a,σ²)—distribution function formula/properties of normal distribution/3σ principle
Γ-distributionΓ(λ,r)
Exponential distribution Γ(λ,1)—distribution function formula/no memory
Random vectors and joint distributions
Definition of random vector/conditions for the establishment of a random vector where the mapping vector ξ is Ω→Rn
Joint distribution and joint distribution function
The formula of joint distribution and joint distribution function/identity map/(Rn, Bn, Fξ) is a probability space
Joint distribution uniqueness theorem: distribution and distribution function are mutually uniquely determined
The properties of the joint distribution function F (4 items) include one more "non-negativity"
Discrete random vector
Definition/Density Matrix/Probability Support Set/Distribution and Distribution Function Formulas/Joint Density Table
continuous random variable
Definition/Density Matrix/Probability Support Set/Distribution and Distribution Function Formulas
Two-dimensional uniform distribution/two-dimensional normal distribution
marginal distribution
Definition/Discrete—Edge Density/Continuity—Calculation of Edge Density Function/Edge Distribution Function
Independence of random vectors
Definition of mutually independent random vectors
The necessary and sufficient condition for two random vectors to be independent of each other is that the joint distribution function variables are separable [If it is specific to discrete type or continuity, the joint density function variable can be separated]
Conditional distributions and generative functions of random variables
conditional distribution function
Discrete random variable conditional density
Discrete full probability formula—when ξ and η are independent of each other, the discrete convolution formula can be used
Conditional density function of continuous random variables
parent function
Definition/mutually independent non-negative integer random variables ξ, η, Gξ η (s) = Gξ (s) Gη (s)
Distribution of functions of random variables
Discrete random variables—defined using probabilities
continuous random variable
Distribution function/density function of a single continuous random variable function
Density formula of sum (continuous convolution formula)
Density formula of quotient
two random variables
Joint density function of continuous n-dimensional random variable ξ (replacement, J)
The distribution of statistics T
Chi-square distribution
Student's t distribution
F distribution
Existence of random variables
monotonic inverse definition
lemma
Random variable existence theorem
random number
Definition (uniformly distributed random numbers)
Use uniformly distributed random numbers to construct random numbers with discrete distribution density/construct exponentially distributed random numbers obeying λ=1/construct standard normal distributed random numbers
Numerical Characteristics and Characteristic Functions
Mathematical Expectation
definition
Definition (Simple Random Variable)—Properties can be proven based on the partitioning of simple random variables
Generalized definition (non-negative random variables)
Continue to promote (general random variables)
Nature (3 items)
Three major theorems: monotonic convergence theorem, Fatou theorem, controlled convergence theorem
The law of large numbers and the central limit theorem
distributed
Cauchy distribution C(λ,μ)
extreme value distribution
Rayleigh distribution
Determination of (joint) distribution function: It can be proved based on the properties of (joint) distribution function
Determination of density function: Prove that this function integrates 1 on (-∞,∞)