<p>I have a decent memory of what I've learned over the year, but my worst area is probably tests (t-test and such) and somewhat confidence intervals. Also, memorizing conditions. Any advice? Good book/site for review on these (and all AP stat topics in general I guess)?</p>
<p>I am also among those getting ready for the AP Statistics exam. It is really good to just thumb through a good review book and go over the subjects you have trouble with. I have been using Barron’s and REA. Be sure to also take plenty of practice MCs, and do FRQs from past years. I’ll post some helpful things to help people get ready. Here are some tips I received on a handout from my teacher:</p>
<p>— TOP NINE PHRASES TO MEMORIZE FOR AP STATISTICS —</p>
<p>regression: interpretation, in context, of:</p>
<ol>
<li><p>r - positive or negative, weak or strong linear association between explanatory variable and response variable.</p></li>
<li><p>r^2 - x percent of the variation in the response variable can be explained by the approximate linear relationship with the explanatory variable.</p></li>
<li><p>slope - for every 1 unit increase in the explanatory variable, our model predicts an average increase of y units in the response variable.</p></li>
<li><p>y-intercept - at an explanatory variable value of 0 units, our model predicts a response variable value of y units.</p></li>
</ol>
<p>confidence intervals: interpretation, in context, of:</p>
<ol>
<li>confidence interval - I’m <strong>% confident that the population proportion/mean of </strong>_ is between __ and __.</li>
</ol>
<p>-or-</p>
<p>I am <strong>% confident that the interval (</strong>,_<em>) captures the true proportion/mean of _</em>.</p>
<ol>
<li>confidence level - If this poll/experiment were repeated many times, then about <strong>% of the resulting confidence intervals would contain the true proportion/mean of __</strong>_.</li>
</ol>
<p>hypothesis tests: interpretation, in context, of:</p>
<ol>
<li><p>p-value - the probability of getting a result as extreme or more extreme than the one observed if the null hypothesis is correct.</p></li>
<li><p>fail to reject the null hypothesis - We do not have enough evidence at the __ level to conclude that the alternative hypothesis is true. </p></li>
<li><p>reject the null hypothesis - At the __ level of significance, there is convincing evidence that the alternative hypothesis is true.</p></li>
</ol>
<p>Thanks, nice list, I’ll memorize some of those.</p>
<p>There is also a great list of the conditions for tests/intervals in this thread:</p>
<p><a href=“http://talk.collegeconfidential.com/ap-tests-preparation/920709-consolidated-list-ap-statistics-hypothesis-testing.html[/url]”>http://talk.collegeconfidential.com/ap-tests-preparation/920709-consolidated-list-ap-statistics-hypothesis-testing.html</a></p>
<p>You guys know the answer to this?</p>
<p>In a large school district, 16 of 85 randomly selected high school seniors play a varsity sport. 19 of 67 randomly selected high school juniors play a varsity sport. A 95 percent confidence interval for the difference between the proportion of high school seniors and high school juniors who play a varsity sport is to be calculated. What is the standard error of the difference?</p>
<p>Answer is 0.0695, but I have absolutely no idea how to get it. Any help?</p>
<p>@zzxjoanw3</p>
<p>First calculate the sample proportions. The proportion of seniors that play is A = 16/85 = .188. The proportion of juniors is B= 19/67 = .284 (note, do not actually round until all calculations are finished). Calculate standard error : Sqrt ( A(1-A)/(samplesizeofA = 85) + B(1-A)/67)
and you get the answer</p>
<p>Use the formula for the standard deviation for the difference of sample proportions when p1 does not equal p2. It’s in the reference table.</p>
<p>Woww that was so easy. Thanks. </p>
<p><a href=“http://www.kent.k12.oh.us/~ke_bmccombs/apstatsl/Exam%20review/2008%20released%20exam.PDF[/url]”>http://www.kent.k12.oh.us/~ke_bmccombs/apstatsl/Exam%20review/2008%20released%20exam.PDF</a></p>
<p>Could you look at numbers 39 and 40 as well?</p>
<p><a href=“Supporting Students from Day One to Exam Day – AP Central | College Board”>Supporting Students from Day One to Exam Day – AP Central | College Board;
<p>Can somebody please explain to me how to do problems 7, 11, 14, and 16 of the multiple choice?</p>