Notation: n manditory problem
(n) helper problem
[n] ungraded problem
{n} optional problem
Note: for several of these problems, I have provided you with part of
the answer. Some correlation coefficients are listed by the problems
and some graphs and more correlation coefficients appear below. This
is to save you the time of doing this work by hand (YUCK!) or going to
a computer.
Remember, unless forbidden, you may use computer software to help you
with other parts of the homework as well, including making graphs.
P.S. Sec probs description
---- --- ----- -----------
#6 1.3 82 proportions bounded by Z scores (Table A)
1.3 85 SAT 800s
1.3 98,99 normal quantile plots
2.2 20 heights of couples [r = 0.565]
2.2 23 changes in units [r=r*=0.253]
2.2 24 alcohol vs. tobacco
[r = 0.784, 0.224; which order?]
2.2 27,28 transformations of data and correlation coef.
1.R 106 types of graphs and their uses
1.R [107] hospital discharges
1.R 108 histograms and numerical stats
1.R [110] driving times
1.R 113 normalizing reading scores
1.R [115] gifted kids
2.6 (81,82) undergrad enrollment (reading a 2-way table)
2.6 83,84 undergrad enrollment (reading a 2-way table)
2.6 89 breaking drug addiction
Extra stuff for HW 6:
2-27: Three scatter plots with correlation coefficient given.
- x
20.0+
-
fuel use-
(l/100km)-
-
15.0+
-
- x x
- x
- x
10.0+ x x r = -0.172
- x
- x x x
- x x
- x x
5.0+
------+---------+---------+---------+---------+---------+speed (kph)
25 50 75 100 125 150
-
fuel use- x
(gallons/-
mile) -
0.075+
-
-
-
- x x
0.050+ x r = -0.172
- x x
- x x
- x x
- x x x
0.025+ x x
-
-
+---------+---------+---------+---------+---------+------speed (mph)
0 20 40 60 80 100
40+ x
- x
fuel use-
(miles/ - x x
gallon) - x r = -0.045
30+ x
- x
- x
- x x
- x
20+ x
- x x
-
-
- x
10+
-
+---------+---------+---------+---------+---------+------speed (mph)
0 20 40 60 80 100
2-28 stuff:
-
30000+
- x
seed -
count - r = -0.470
-
20000+
-
-
- x
- x
10000+
- x
- 2
- x
- 2 2
0+ x 2 2 x x x
+---------+---------+---------+---------+---------+----
0 1000 2000 3000 4000 5000 seed weight
-
-
10.0+ x
- x x r = -0.929
log of - x
seed - x x
count - x x
7.5+ x x
- x
- x
- x x
- x
5.0+ x
- x x
-
- x
-
+---------+---------+---------+---------+---------+------
-2.0 0.0 2.0 4.0 6.0 8.0 log(seed wght)
This page maintained by:
Randall Pruim
Department of Mathematics and Statistics
Calvin College
rpruim@calvin.edu