AP Stats EOY Review

Just the ones remaining

What is an Influential Point?

A point that strongly affects the slope or position of the regression line.

What is a High Leverage Point?

A point with an extreme x-value that can strongly influence the regression line.

How do you calculate Expected Counts in chi-square?

Expected = r*c / total

What is Marginal Frequency?

Total counts for one variable (sum across rows or columns in a table).

What is Conditional Frequency?

The frequency of one variable given a condition on another variable (row or column percents).

What is Joint Frequency?

Counts for combinations of two categorical variables (inside table cells).

What is the Empirical Rule

In a normal distribution: 68% within 1 SD, 95% within 2, 99.7% within 3.

What is the Large Counts Condition?

np ≥ 10 and n(1 - p) ≥ 10 for using normal approximation for p̂.

What is a Type I Error?

Rejecting H₀ when it is actually true.

What is a Type II Error?

Failing to reject H₀ when it is false.

What is the Power of a Test?

The probability that the test correctly rejects a false H₀.

What are the conditions for chi-square?

Random sample, all expected counts ≥ 5.The data should also be independent and follow a categorical distribution.

What is the Multiplication Rule (General)?

P(A and B) = P(A) × P(B

What is the Multiplication Rule (Independent)?

P(A and B) = P(A) × P(B) if A and B are independent.

What is the Mean Rule for combining random variables?

μ_{X + Y} = μ_X + μ_Y.

What is the Variance Rule for combining random variables?

σ²_{X + Y} = σ²_X + σ²_Y (if X and Y are independent).

DUFS

direction, unusual features, form, strength

SOCV

Shape, Outliers, Center, Variability

BINS

Binomial, Independent, Number of trials fixed, same prob of sucess

BITS (geometric)

Binary, independent, unfixed trials, same prob of success

What does geopdf calculate?

The probability the first success happens exactly on the k-th trial.

What does geocdf calculate?

he probability the first success happens on or before the k-th trial.

What does binompdf calculate?

The probability of getting exactly k successes in n trials.

What does binomcdf calculate?

The probability of getting k or fewer successes in n trials.

What’s the key difference between a pdf and a cdf?

A pdf gives probability of an exact value; a cdf gives cumulative probability up to that value.