I will give you, on the test,
the formulas for SD(p-hat), SD(x-bar), n for given C and ME.
The rest you need to memorize.
LaReina will not be available Thursday
night (lacrosse championships). She Will be available "extra" Wed
12:30-2. I'll be on campus midday Thursday; 11:30-12:30 and 1:45-2:15
only.
Day 35 WED. April 27: (Re)Reading:
Chapter
20+21 thru p. 392 (Activstats is good here too.) Then continue (Alpha
levels) through 397. Lightly through Power. Read What can
go wrong p. 401 and the rest. (SPSS won't do proportion computations,
but some other programs do; it's good to have an idea what you might see,
p. 402.) Next: Chapter 23, Means.
| Hand in (All D&V)
Part of Wednesday
(If we get there (we didn't)- -
- - - - - - - - - )
A. Use the T-table to decide these questions: a) Ho: p = .3 vs. HA: p>.3. z from p-hat is 2.12. Is it significant at the .01 level? .05? .10? b) Ho: p = .3 vs. HA: p not = .3. z from p-hat is 2.12. Is it significant at the .01 level? .05? .10? c) Ho: p = .3 vs. HA: p>.3. z from p-hat is 3.16. Is it significant at the .01 level? .05? .10? p. 387, #11 (use p.397--CI's & Tests) |
Read,
to discuss |
Optional |
Homework questions? Day
32 ,
(From email:) I'm still looking
at 3d, chapter 20. I can't figure out what they think
they're saying there, but as far as I can see, what they're actually
saying is wrong. The buzzwords are in there but put together
wrong.
What I see them saying is that
P(Ho true) = 22%. ("Poll results could be just natural sampling variation"
means Ho, no change, is true.) And that's just plain wrong.
So all the answers are wrong.
4d is a *good* correct answer,
when Ho is "die is fair"
While I'm at it, 2c is not very
well posed either. Our alternatives are always of the form <,
> or not equal to. But they're interested in showing "at least 60%",
which is >.
Their answer is Ho: p = .60,
Ha: p>.60. Which is not exactly appropriate but the best we can do.
If they had said "...if we are
sure that MORE THAN 60% of the people like [it]" their answer would be
appropriate.
alpha questions Day
33
Questions for test? Note
"Sample exam" Correction: p.
388 425 #15 Twins
New material Not covered. Day
34
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