## STAT 303, 503-504, Spring 1996

Prof. H. Joseph Newton

Exam 1 Results

### Correct Answers

- (#12 on form B) c, d
- (#13) sampling without replacement
- (#14) (a) mean decreases by 2,000, (b) median stays the same
- (#4) R^2 is between 0 and 1
- (#11) a
- (#6) .9899 for form A, .9066 for form B
- (#7) -.74 for form A, -.18 for form B
- (#8) any three of mu=population mean, sigma=population standard deviation,
sigma^2=population variance, pi=proportion of 1's in a 0-1 population
- (#9) Any 2 of a, b, c
- (#10) c, f (not a because it's sampling without replacement)
- (#11) (a) slope=33.0199, intercept=-3186.05, (b) I accepted any
r between .5 and .9, (c) intercept is value of y (weight) when x (length)
is 0 and a car having length 0 makes no sense.
- (#1) (a) at least 75 % (note that sigma=2), (b) is 95%
- (#2) a and d
- (#3) average value=1(.2)+2(.2)+3(.2)+4(.2)+5(.1)+6(.1)=3.1
- (#15) sort the digits of your ID, then get Q1=median of 5 smallest
digits and Q3=median of 5 largest digits, and then IQR=Q3-Q1

### Results

Mean=63.12, Std. Dev=16.60
Q1=52, Q2=64, Q3=74, IQR=22
2* | 4
2. | 6
3* | 04
3. | 66888
4* | 04
4. | 66899
5* | 000222244
5. | 6666688
6* | 0002222334444
6. | 668889
7* | 0000012344444
7. | 666688
8* | 0014
8. | 568
9* | 02244
9. | 8

### The Curve!

A: 80-100 (13)
B: 65-79 (25)
C: 46-64 (34)
D: 34-45 (8)
F: <34 (3)