Write the formula for the mean of grouped data. (21-10)

Class 1 - 1/16/18 • Terminology o Response (dependent variable): the variable of interest to be measured in the experiment o Factors (independent variables): variables whose effect on the response is of interest to the experiment • Quantitative factors; numerical scale • Qualitative (categorical) factors; non-numerical ▪ WHAT ANOVA USES! o Factor levels: the different values of the individual factors o Treatments: factor-level combinations within multiple factors • Ex/ Factor A: gender (male and female) and Factor B: age (young, middle, and old) --> 6 treatments o Experimental unit: the object on which the response and factors are observed or measured o Experimental study: the researcher controls the specification of the treatments and the method of assigning the experimental units to each treatment o Observational study: the researcher simply observes the treatments and response on a sample of study units o Balanced design: same number of experimental units per treatment o Randomization: the process of assigning experimental units to a control or experimental group on a random basis (e.g., flipping a coin) • Minimizes the differences among groups regarding any particular characteristics to avoid any potential bias o Blinding o Blocking: • Constrained randomization: b