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What is the cumulative distribution function (CDF) of the geometric distribution used for?
The probability of achieving up to a certain number of trials to achieve the first success
What are Bernoulli Trials in the context of the geometric distribution?
Independent trials with two possible outcomes and a constant probability of success p
How does the pmf of the geometric distribution calculate the probability of needing k trials to achieve the first success?
P(X=k)=(1−p)k−1⋅p
What does the hypergeometric distribution model?
The number of successes in a fixed number of draws without replacement from a finite population
What type of probability distribution is the hypergeometric distribution?
Discrete probability distribution
How does the pmf of the hypergeometric distribution calculate the probability of obtaining exactly k successes in a sample?
P(X=k)=(K¦k)((N-K)¦(n-k))/((N¦n) )
What distinguishes the hypergeometric distribution from the binomial distribution?
Accounting for sampling without replacement
What is the population size parameter in the hypergeometric distribution?
N
In which situations is the hypergeometric distribution commonly used?
Modeling the probability of obtaining a specific number of successes in a sample drawn without replacement from a finite population
What is one challenge related to the hypergeometric distribution?
Finite Population Assumption
What are examples of scenarios where the hypergeometric distribution can be applied?
Sampling without replacement from a deck of cards, Quality control scenarios
What is the sample size parameter in the hypergeometric distribution?
n
What does the hypergeometric distribution assume about the samples drawn from the population?
They are drawn without replacement
What is the definition of the marginal distribution?
Obtained by summing (or integrating) the joint distribution over all possible values of the other variable(s)
What type of probability distribution is the marginal distribution?
Can be discrete or continuous
What is one challenge related to the marginal distribution?
Loss of Information
How is the marginal probability mass function (PMF) obtained for discrete random variables?
By summing probabilities over the values of the other variables
In which situations are marginal distributions commonly used?
Analyzing individual variables in a multivariate setting
What does the joint distribution describe?
Probabilities associated with all possible combinations of values that two random variables can take simultaneously
What distinguishes the chi-square distribution from other distributions?
It is skewed to the right and has no negative values
What concept is important in using the chi-square distribution for hypothesis testing and confidence interval estimation?
Degrees of Freedom (ν)
What challenge is associated with the chi-square distribution?
Sensitivity to Sample Size
How is the joint probability mass function (PMF) represented for continuous random variables?
As a joint probability density function (PDF)
What is the uniform distribution characterized by?
A constant probability density function (pdf) over the range of possible values
How does the cumulative distribution function (CDF) behave in a uniform distribution?
Increases linearly within the range from 0 to 1
In what type of scenarios is the uniform distribution commonly used?
Simulations, random number generation, and modeling situations where all outcomes are equally likely
What is one challenge associated with the uniform distribution?
Limited Applicability
What is an example of a continuous uniform distribution?
Selecting a random number from a specified interval [a, b] with equal probability for any value within that interval
What concept is central to the uniform distribution's probability density function (pdf)?
Equal probability for all outcomes within the specified range
What distinguishes the uniform distribution from other distributions in terms of probability density function (pdf)?
Constant pdf over the range of possible values
What is one usage of the uniform distribution in statistical experiments?
Modeling scenarios where there is no reason to favor one outcome over another within the specified range
What type of probability distribution is the uniform distribution?
Continuous and can be discrete
What does the uniform distribution model within a given range?
All outcomes are equally likely
What are the two different types of data in statistics?
Discrete data and continuous data
Define discrete data.
Discrete data involves variables that have specific values that cannot have values between them.
Give an example of a discrete variable.
The number of times someone visits their neighbors during the week.
Why is the number of times someone visits their neighbors during the week considered a discrete variable?
Because it has specific values and cannot have values between them.
Are categorical variables considered discrete or continuous variables?
Discrete variables
What is continuous data?
Variables in which there could be an infinite number of values between a set range of possible values
Give an example of a continuous variable.
Final exam grades on a scale of 0 to 100
Why are final exam grades considered a continuous variable?
Because there could be an infinite number of values between them
What are things measured in time considered as?
Continuous variables
Can someone express their age in a continuous manner?
Yes
What is a symmetrical distribution?
When the pattern or trend of frequencies on the left and right side of the distribution are the same.
Define a skewed distribution.
When the scores pile or stack up on one side and are spread out on the other.
What are the two types of skewed distributions?
Positive skew and negative skew.
What is a positive skew?
When the scores pile up on the lower end of the values with fewer scores at the high end.
What is a negative skew?
When the scores pile up on the higher end of the values with fewer scores at the low end.
What types of distributions are specifically used for discrete data?
Discrete data distributions such as the binomial distribution.
What is the Chi-Square distribution used for?
Statistical tests such as the chi-square test for independence and goodness-of-fit tests.
What distribution is used to model the number of events occurring in a fixed interval of time with a known average rate?
Poisson distribution
Which distribution is symmetric and bounded between 0 and 1, often used for modeling growth or response curves in logistic regression?
Logistic distribution
What distribution is used to model variables that are positively skewed, such as income or asset prices?
Log-normal distribution
What is the joint distribution of two or more random variables?
Describes the probabilities of all possible combinations of values that these variables can take simultaneously.
What distribution is used to model the time until k events occur in a Poisson process with a constant rate?
Gamma distribution
What distribution is a generalization of the normal distribution and allows for varying degrees of tail weight and skewness?
Exponential power distribution
What distribution is used to model the number of trials needed to achieve the first success in a sequence of independent Bernoulli trials?
Geometric distribution
What distribution is commonly used in analysis of variance (ANOVA) and regression analysis?
F-distribution
What distribution is often used to model the time until failure in reliability engineering and survival analysis?
Weibull distribution
What is the normal distribution also known as?
Gaussian distribution
What are the two parameters that describe the normal distribution?
Mean (μ) and standard deviation (σ)
What is the Central Limit Theorem related to the normal distribution?
The sampling distribution of the sample mean approaches a normal distribution as the sample size increases
What is the standard normal distribution?
A special case of the normal distribution where the mean is 0 and the standard deviation is 1
What is one of the challenges related to the normal distribution in statistical analyses?
Assumption of Normality
What are examples of data that often follow a normal distribution?
Heights and weights of individuals in a population, test scores such as SAT scores
What does the binomial distribution represent?
The frequency of data with two outcomes
What are the two possible outcomes in a binomial distribution?
Pass and fail
What does the term "Bernoulli trials" refer to in the context of the binomial distribution?
Trials with two possible outcomes and a constant probability of success p
How many parameters characterize the binomial distribution?
Two parameters
What is the probability mass function (pmf) of the binomial distribution used for?
Giving the probability of observing a specific number of successes in n trials
In which fields is the binomial distribution commonly used?
Quality control and finance
What assumption does the binomial distribution make about the outcomes in each trial?
They are independent and identically distributed (i.i.d.)
What is one challenge related to the binomial distribution in statistical analyses?
Independence Assumption
What are examples of data that often follow a binomial distribution?
Flipping a fair coin n times and counting the number of heads, Testing the success rate of a new drug
What is the cumulative distribution function (CDF) of the binomial distribution used for?
The probability of observing up to a certain number of successes in n trials
What does the geometric distribution model?
The number of trials needed to achieve the first success in a sequence of independent trials
What type of probability distribution is the geometric distribution?
Discrete probability distribution
What does it mean for the geometric distribution to be memoryless?
The probability of achieving success in the next trial remains the same regardless of previous outcomes
What is the probability mass function (pmf) of the geometric distribution used for?
Giving the probability of needing exactly k trials to achieve the first success
In which situations is the geometric distribution commonly used?
Modeling the probability of achieving success for the first time after a series of independent trials
What is one challenge related to the geometric distribution?
Infinite Expected Value
What are examples of scenarios where the geometric distribution can be applied?
The number of attempts needed to score a goal in a soccer game, Tossing a fair coin until it lands heads

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