Graduation, again As in Exercise 29, we hope to estimate the percentage of adults aged 25 to 30 who never graduated from high school. What sample size would allow us to increase our confidence level to 95% while reducing the margin of error to only 2%?

Week 2: Lecture 3 ● Spread: How much the data values vary around each other. ○ Range: How far apart are the two extremes. Also, sensitive to outliers. (e.g. range= max-min) ● Interquartile Range: the value that is just above the lower 25% of the data values, namely Q 1 ○ Range of middle half of the data ■ IQR = Q - Q *IQR is like median, not affected by outliers or 3 1 skewness of distribution ● Upper Quartile (3rd Quartile): the value that is just above the lower 75% of data values, namely Q 3 ■ E.g. 150 150 152 154 156 I 156 157 157 158 159. Answer: Q =152, Q =157 1 3 ● Standard deviation: measures how far the data values are f