Common Probability Distributions
2026年01月15日
Common Probability Distributions
Continuous Uniform Distribution:

Binomial distribution
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● E(X)=np
● D(X)=np(1-p)
Poisson Distribution
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● E(X)=λ
● D(X)=λ
Normal Distribution:
● Completely described by mean and variance (μ,σ2).
● It is symmetric with skewness measure of 0,i.e.,mean=mode=median.(https://www.daowen.com)
● Kurtosis=3.
● Linear combinations of normal random variables are normally distributed.
● Standardized Normal Distribution
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● Confidence Interval
68% of observations fall within±1σ.
90% of observations fall within±1.65σ.
95% of observations fall within±1.96σ.
99% of observations fall within±2.58σ.
Student's t-distribution:
● Student's t-distribution:is symmetric;fatter tails;
● Degrees of freedom=(n-1).