Inference for Proportions and Means

Flashcards created from lecture notes on Inference for Proportions and Means, covering key concepts, definitions, and statistics-related terms.

Margin of Error (ME)

The maximum expected difference between the true population parameter and a sample estimate.

Standard Error of Proportion (SEP)

The standard deviation of the sampling distribution of a sample proportion.

Confidence Level (C%)

The percentage of all possible samples that can be expected to include the true population parameter.

Critical Value (z or t)

The value from the z-table or t-table that corresponds to the desired confidence level.

Degrees of Freedom (df)

Calculated as n - 1 for t distributions, used to determine critical values.

Random Sampling

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

Central Limit Theorem (CLT)

States that the sampling distribution of the sample mean will be normally distributed if the sample size is sufficiently large.

p-value

The probability of obtaining a test statistic at least as extreme as the one observed, assuming the null hypothesis is true.

Hypothesis Testing

A method of statistical inference to decide whether there is enough evidence to reject a null hypothesis.

Type I Error (α)

The incorrect rejection of a true null hypothesis.

Type II Error (β)

The failure to reject a false null hypothesis.

Power of a Test

The probability that the test correctly rejects a false null hypothesis.

Two-Sample t Interval for Means

A confidence interval used to compare the means from two different samples.

1-PropZInt

A function on the TI-84 calculator used to calculate the confidence interval for one sample proportion.

2-PropZInt

A function on the TI-84 calculator used to calculate the confidence interval for the difference between two sample proportions.

Test Statistic (z or t)

A standardized value that is calculated from sample data during a hypothesis test.

Conclusion in Hypothesis Testing

The decision made based on the comparison of p-value and significance level concerning the null hypothesis.

Confidence Interval

A range of values derived from sample statistics that is likely to contain the value of an unknown population parameter.