1.23 Medical students. Students who have finished medical school are assigned to residencies in hospitals to receive further training in a medical specialty. Here is part of a hypothetical data base of students seeking residency positions. USMLE is the student's score on Step 1 of the national medical licensing examination.
Name | Medical school | Sex | Age | USMLE | Specialty sought |
---|---|---|---|---|---|
Abrams, Laurie | Florida | F | 28 | 238 | Familty medicine |
Brown, Gordon | Meharry | M | 25 | 205 | Radiology |
Cabrera, Maria | Tufts | F | 26 | 191 | Pediatrics |
Ismael, Miranda | Indiana | F | 32 | 245 | Internal medicine |
1.26 Facebook, Twitter, and LinkedIn users. After years of explosive growth in number of users of social networking sites in all age ranges and demographics, it is hard to argue that social media haven't changed forever how we interact and connect online. Although Facebook is still the dominant players in social networking, both Twitter and LinkedIn have continued to increase their usage. Here is the age distribution of the users for the three sites in 2013: SOCIALNT
Age | Facebook Users | Twitter Users | LinkedIn Users |
---|---|---|---|
13 to 17 years | 10% | 10% | 4% |
18 to 24 years | 14% | 18% | 10% |
25 to 34 years | 19% | 22% | 20% |
35 to 44 years | 17% | 17% | 18% |
45 to 54 years | 17% | 15% | 20% |
55 to 64 years | 13% | 11% | 17% |
Over 65 years | 10% | 7% | 11% |
1.35 Where are the nurses? The following spreadsheet gives the number of active nurses per 100,000 people in each state. NURSES
2.25 Incomes of college grads. According to the Census Bureau's Current Population Survey, the mean and median 2012 income of people at least 25 years old who had a bachelor's degree but no higher degree were $50,281 and $62,597. Which of these numbers is the mean and which is the median? Explain your reasoning.
2.32 Maternal age at childbirth. How old are women when they have their first child? Here is the distribution of the age of the mother for all firstborn children in the United States in 2012:
Age | Count | Age | Count | |
---|---|---|---|---|
10 to 14 years | 3,578 | 30 to 34 years | 299,857 | |
15 to 19 years | 251,022 | 35 to 39 years | 106,892 | |
20 to 24 years | 461,553 | 40 to 44 years | 24,251 | |
25 to 29 years | 421,704 | 45 to 49 years | 1,952 |
The number of firstborn children to mothers under 10 or over 50 years of age represent a negligible percentage of all first births, and are not included in the table.
2.50 Graduation rates. In Exercise 1.10 (page 32) you were asked to use a stemplot to display the distribution of the percents of on-time high school graduates in the states. Stemplots help you find the five-number summary because they arrange the observations in increasing order. GRADRATE
5 | 9
6 | 23
6 | 788
7 | 112444
7 | 56666777888
8 | 0001122333333344
8 | 666666778