2. HYPOTHESIS TESTING:
Differenceinmeans test: compute the tstatistic:
COMPUTE THE TSTATISTIC:
3. CONFIDENCE INTERVAL:
A 95% confidence interval for the difference between the means is:
confidence intervals are closely related for hypothesis testing
CONCEPTS REVIEW:
RANDOM VARIABLE:
informally, a random variable gives you a number that's determined by outcomes of underlying experiments
concept of random variable is closely related to experiments & experimental outcomes
in stats, the term experiment is used more broadly

e.g the experiment here may include some complicated underlying process that determines the gender,
weight, size etc. of a newborn baby

e.g some unknown process that determines a graduates first salary & its difference for the salary of a high
school graduate
referred to as an experiment