Honors Physics Fitting
Functions to Data
Chapter 8 Packet
Suggestions on Specific Problems
Exploration
8-2b
9. Change the question to read: On a separate sheet of paper, write a
paragraph stating where the coefficient of determination shows up in Excel. Explain …
Exploration
8-2c
We will
skip this one for now.
Exploration
8-3a
1. Inserted below is how your Excel sheet should
look like. Notice that you have to graph years from 1970 vs. # of violent
crimes on a specific set of years. Using
the linear regression equation and a value of 5 for x (since 1975 is 5 years
from 1970) you should compare the actual 1975 datum to your predicted y value
from LR. It should be within 6500 – a 1.3%
difference.
|
Year |
Change from 1970 |
# of violent crimes |
|
Change from 1970 |
# of violent crimes |
|
|
|
|
|
1970 |
0 |
|
|
0 |
|
|
|
|
|
|
1971 |
1 |
323060 |
|
1 |
|
|
|
|
|
|
1972 |
2 |
350410 |
|
2 |
|
|
|
|
|
|
1973 |
3 |
380560 |
|
3 |
|
|
|
|
|
|
1974 |
4 |
429350 |
|
4 |
429350 |
|
|
|
|
|
1975 |
5 |
451310 |
|
5 |
|
|
|
|
|
|
1976 |
6 |
411630 |
|
6 |
|
|
|
|
|
|
1977 |
7 |
435720 |
|
7 |
|
|
|
|
|
|
1978 |
8 |
469700 |
|
8 |
|
|
|
|
|
|
1979 |
9 |
467700 |
|
9 |
|
|
|
|
|
|
1980 |
10 |
475160 |
|
10 |
|
|
|
|
|
|
1981 |
11 |
490460 |
|
11 |
|
|
|
|
|
|
1982 |
12 |
526200 |
|
12 |
|
|
|
|
|
|
1983 |
13 |
499390 |
|
13 |
|
|
|
|
|
|
1984 |
14 |
493960 |
|
14 |
|
|
|
|
|
|
1985 |
15 |
497560 |
|
15 |
|
|
|
|
|
|
1986 |
16 |
553900 |
|
16 |
|
|
|
|
|
|
1987 |
17 |
546300 |
|
17 |
|
|
|
|
|
|
1988 |
18 |
625900 |
|
18 |
|
|
|
|
|
|
1989 |
19 |
685500 |
|
19 |
685500 |
|
|
|
|
|
1990 |
20 |
705500 |
|
20 |
705500 |
|
|
|
|
|
1991 |
21 |
718890 |
|
21 |
718890 |
|
|
|
|
|
1992 |
22 |
742130 |
|
22 |
742130 |
|
|
|
|
|
1993 |
23 |
754110 |
|
23 |
754110 |
|
|
|
|
|
1994 |
24 |
778730 |
|
24 |
778730 |
|
|
|
|
|
1995 |
25 |
796250 |
|
25 |
796250 |
|
|
|
|
|
1996 |
26 |
729900 |
|
26 |
|
|
|
|
|
|
1997 |
27 |
717750 |
|
27 |
|
|
|
|
|
2. Here you want to use the equation from the
linear regression above and the data from the years 1985 and 1997 to compare
predicted values to the actual data in the table.
3. All is well on this one.
4. You should plot both lines on your
graph. Save the graph as a new sheet so
that it is big.
5. Remember that quadratic functions with a
negative coefficient are convex and decreasing.
When adding a Trend line,
choose Type - Polynomial and the Order set at 2.
You should get an R2 = .919