Distributions(Udemy Statistics for Data Science and Business Analysis) Flashcards
What is inferential statistics?
Methods that rely on probability theory and distributions to predict population values using sample data
What is a distribution?
A distribution is a function that shows the possible values for a variable and how often they occur
What is a discrete uniform distribution?
When all outcomes have an equal chance of occurring, such as when rolling a die
Is a distribution defined by the graph or by underlying probabilities?
It is defined by underlying probabilities
For what distribution is the mean, median, and mode equal?
Normal Distribution
Which distribution has no skew?
The normal distribution
What is a z score?
A z score tells us how many standard deviations the value is from the mean of a given distribution
What is the standard normal distribution?
Where the standard deviation is 1 and the mean is 0, other normal distributions can be standardized to this version
What is a sampling distribution?
A distribution formed by samples
What does the Central Limit Theorem State?
No matter the distribution of the sample, a sampling distribution of the mean will approximate the normal distribution
What is one thing that will make your statistical results more accurate?
Drawing larger samples
What does the Central Limit Theorem allow us to do?
The central limit theorem allows us to perform tests, solve problems, and make inferences using the normal distribution, even when the population is not normally distributed
What is the Standard Error?
The standard error is the standard deviation of the distribution formed by the sample means, in other words the standard deviation of the sampling distribution
What is the difference between the standard deviation and the standard error?
Standard deviation and standard error are both measures of variability. The standard deviation describes variability within a single sample, the standard error estimates the variability across multiple samples of a population
What is the meaning of the standard error?
Is it the variability of the means of the different samples that we extracted
