Body fat Do the data shown in the table below indicate an association between Waist size and %Body Fat? a) Test an appropriate hypothesis and state your conclusion. *b) Give a 95% confidence interval for the mean %Body Fat found in people with 40-inch Waists.

Ch. 3 Statistical Descriptions of Data • Measures of Central Tendency & Dispersion: these show the center and variability and are calculated for numerical summaries • Measures of Central Tendency: describe the typical values of the data o Show the center of gravity/middle of the data • Mean (Average): add all the values and then divide by the number of values o Sample Mean: sum of the observations divided by the sample size (n) ̅ o A bar over a letter means the average, so X means the average of all values of X Σx o Equation: X= i n o The mean is not resistant to outliers; outliers will sway the mean •