Lecture Notes Flashcards

Flashcards for reviewing lecture notes.

Sample

A small subset of a population.

Population Parameters

Descriptive measures of a population (e.g., mu for population mean, sigma for population standard deviation).

Sample Statistic

A descriptive measure calculated from a sample (e.g., x̄ for sample mean).

Sampling Distribution

The distribution of a statistic (e.g., sample mean) calculated from multiple random samples of the same size taken from a population.

Standard Error

The standard deviation of the sampling distribution of the sample mean.

Central Limit Theorem (CLT)

States that the sampling distribution of the sample mean approaches a normal distribution as the sample size increases, regardless of the shape of the population distribution.

T-Statistic

A test statistic used when the population standard deviation is unknown and estimated by the sample standard deviation.

T-Distribution

A probability distribution that is similar to the normal distribution but has heavier tails; used in hypothesis testing when the population standard deviation is unknown and estimated by the sample standard deviation.

Degrees of Freedom

The number of independent pieces of information available to estimate a parameter.

Estimator

A method or formula used to estimate a population parameter.

Estimate

A specific value or numerical result obtained by applying an estimator to a sample of data.

Point Estimate

A single number that estimates the value of a population parameter.

Unbiased Estimator

An estimator whose expected value is equal to the population parameter it is estimating.

Consistent Estimator

An estimator that converges to the true population parameter as the sample size increases.

Efficient Estimator

An estimator with the smallest variance among all unbiased estimators.

Random Sample

A sample in which each member of the population has an equal chance of being selected.

Representative Sample

A sample that accurately reflects the characteristics of the population from which it is drawn.

Confidence Interval

A range of values within which a population parameter is estimated to lie, with a specified degree of confidence.