DE Statistics Final Review

Front

What is the standard deviation?

Back

A measure of the amount of variation or dispersion in a set of values.

Front

How do you calculate the probability of A or B when A and B are independent?

Back

P(A or B) = P(A) + P(B) - P(A and B) = P(A) + P(B) since A and B are independent.

Front

What is the formula for determining sample size for estimating a proportion?

Back

n = (Z^2 * p * (1-p)) / E^2, where Z is the Z-score, p is the estimated proportion, and E is the margin of error.

Front

What is an observational study?

Back

A study where the researcher observes and measures behavior without manipulating any variables.

Front

What is confounding in experimental design?

Back

When the effects of two or more variables are mixed, making it difficult to determine the individual effect of each variable.

Front

What is the purpose of a control group in an experiment?

Back

To provide a baseline for comparison against the experimental group.

Front

What is the difference between a survey and an experiment?

Back

A survey collects data without manipulation, while an experiment involves manipulation of variables to observe effects.

Front

What does a 95% confidence level mean in statistics?

Back

It means that if the same population is sampled multiple times, approximately 95% of the confidence intervals calculated from those samples will contain the true population parameter.

Front

What is the significance of a p-value in hypothesis testing?

Back

A p-value indicates the probability of obtaining the observed results, or more extreme results, if the null hypothesis is true.

Front

What is a matched pairs design?

Back

An experimental design where subjects are paired based on certain characteristics, and each pair is subjected to different treatments.