Urgent DSST Stat Question

[Llyssia]

Hi all--I have my test tomorrow and have been studying forever--it seems like something always becomes an emergency at the last minute. This time it's that I just heard that the Z table the test uses is not the IC one, it must be the one that covers the whole curve percentwise, not just half--the same one Sal uses on Khan Academy. i've been studying all day and have no brain left. Can someone tell me, with this Z table that covers the whole area under the curve, what the differences in thinking are--for instance for an interval on a two tailed test, I guess you have to subtract out the 50% and then double it? I kind of ignored the Khan info since I thought the test would be using the IC table. From what I also hear, use of the Z table seems minimal anyway. I'm just really uncomfortable about this whole thing. Can't wait til it's over! Thanks for any insights.

[Prloko]

I brought a non-programmable calculator with Stats functions and didn't need the z table. I can't remember what the table looked like, but I think it was the half table. If you have most of the formulas covered you will most likely pass. This exam has a liberal curve.

[LaterBloomer]

Good luck, Llyssia. Please let us know how you did.

[Llyssia]

Wow, I passed with a 468! Another "if I can do it anyone can do it" miracle. I don't know whether to post anything in the feedback section. The only thing I may have to add is a suggestion to definitely know how to access all tables, especially the Z and T ones (frankly, I didn't know what the other two were!!), before beginning the test. If I had it to do over again, I would have asked the proctor how to go back to the beginning of the test (tables are numbers 1-4). I couldn't figure this out on my own and so was using what I remembered of the percentages contained within each standard deviation to estimate which answer was closest on all the questions involving use of the Z table. I guess it worked, though, maybe. And another concern is that the IC Z table we use to learn on is different from the one on the test. I did see that mentioned somewhere in this forum, unfortunately only two days before the test and I couldn't get confortable with the table with the %s being the whole area under the curve, not just 50%. I think the IC people should be contacted on this if the tests have this other table. The test table is the same table Khan Academy uses but it also has the negative Z scores included. I believe this is called a cumulative table. Once I found out how to access the table during the test I couldn't make the conversion with my stressed out brain! Thanks for the support. It really helped.

[Llyssia]

PS--Just out of curiosity, I'd love to know how you used the stats functions on your calculator to bypass the need for a Z table. I also read that recommendation 2 days before the test and couldn't get used to the stat functions on my BAIIplus (not hard, I just could have used a little more time)--maybe it didn't even have enough to do what you did on your calc.

[cookderosa]

Congrats on your pass!:hurray:

[LaterBloomer]

Wow! 468? Very impressive. Congratulations, and thanks for letting us know about possible glitches so we can study appropriately. Thanks, also, for your specific feed-back in the specific feed-back section.