Wednesday, April 30, 2008

Answers for O #1-5

O-1a) 40% of the sales agents had sales of $300,000 or less.
O-1b) 10% (show work!)
O-1c) No agents had sales between $1 million and $1.1 million
O-1d) $800,000 (with explanation!)
O-2a) 2-prop z-interval (name or formula)
success = 188, 180 > 10
failures = 12, 20 > 10
Independent samples
(-0.0156, 0.0956)
We are 96% confident that the difference in the proportions of parts meeting specs for the two shifts is between -0.0156 and 0.0956.
O-2b) No, because 0 is in the interval, zero is a possible value. So we are 96% confident that zero difference in shift specs is possible. We make this decision using alpha = 0.04!!
O-3a) z > 1.14 = 12.71%
O-3b) 1 - (8729)^5
O-3c) invnorm(0.99) = 2.33
algebra: (291.2 - M)/2.8 = 2.33

M =
Show work!!!
O-4): matched pairs t-test
Ho: mu = 0
Ha: mu > 0 (mean diff (after - before) is greater than 0)
Name or formula: t = (x-bar - 0)/(s/sqrt(n))
SRS and graph to check nearly normal
t = 3.75
df = 11
p-value = 0.002
Reject Ho. Is evidence that people who complete program have increased dexterity.
O-5a)
rv: amount of draft
treatments: standard hitch and new hitch
experimental units: 2 large plots of land
O-5b)
Yes, the hitches are randomly assigned to the plots.
O-5c)
No. Each treatment was applied to only one plot. Replication is needed.
O-5d)
Even though 25 measurements were taken, each hitch was used on only one plot only. If a difference in the draft is observed, we will not know whether the difference is due to the hitch or the plot. The treatment (hitches) are confounded with the plots.

Name that green sheet

I-5c:  Chi-square goodness of fit
J-5:  Chi-sq 2-way table or 2-prop z
K-4:  2-mean t-interval
L-4:  1-prop z-test
M-4:  mp's 1-mean t-interval
N-4:  2-prop z interval
O-2:  2-prop z interval
O-4:  mp's 1 mean test
P-4:  mp's 1 mean t test
Q-5:  2-mean t test

Monday, April 07, 2008

Calendar info

Below you see the link for the review calendar. Please note:

**Click on "Week" to view a week at a time and better see the details
of what we did each day.

**Homework and classwork is listed for each day.

I hope this is helpful!

Sunday, April 06, 2008