Bio AP and chi squares

<p>Would the AP ever have a chi square test question? If it did, would have the formula and all the values, or do we have to have them memorized? well, i guess they would give us the vaues, but the formula? i cant remember it for some reason...</p>

<p>whats a chi square...</p>

<p>wait isn't that statistics?</p>

<p>I think the only equation you need for bio is the Hardy- Weinberg equation (and it only helps you out on at most two questions)</p>

<p>you guys didnt do chi squares? i think it is statistics, but it was part of the pop. genetics lab (the drosiphila one). Maybe some manuals do have it and others dont...</p>

<p>Yeah , X^2 (chisquare) is from the genetics lab and also in statistics! The formula is [(Observed - Expected)^2 ] / Expected. Check out the lab though for info on degree of freedoms related to that</p>

<p>sigh... i have to go relearn it... chi squares are evil... does it take others forever to do it? Forever being almost 10 minutes, or am i just slow?</p>

<p>I took 3 practice MC exams and looked at the Pree response and saw nothing aoboutt chi squares</p>

<p>It might come up in the lab questions, however since it's the kind of formula that takes a little while (and actually involves some math..we aren't allowed to use calculators, are we?) I don't forsee a question like "What is the chi square value for this data set" or something.</p>

<p>We just reviewed labs and chi-squares last Thursday. My teacher said if they do use it for the lab-based free response question, they'll have a table for you. All the test-taker would need to know is the [(o-e)^2]/e formula. My bio teacher didn't introduce this to us until four days ago 'cause he said it's very unlikely that chi-squares will appear on the test besides maybe one part of the lab-based FR question.</p>

<p>Just to add to what winterpolaris said, make sure you know what degrees of freedom are and how to use them to read the table and decide if your null hypothesis is valid.</p>

<p>yay, thanks guys! I guess i have to try and remember it... O well... Off to the books!!</p>

<p>i think last years free response had a chi squares test but it was really easy, you just plug in the numbers and read off the charts</p>

<p>wow, AP stats is actually useful for something</p>

<p>lol</p>

<p>and i think the degree of freedom is phenotypes - 1 .</p>

<p>df is always Number of categories minus 1 in a chi square...</p>

<p>i took stats last year, got a 5. This year im taking bio. you only need to know the chi square if the genetics lab comes up. no big deal.</p>

<p>yay, my bio teacher told us about old tests today... There was a chi square within the last year or two, and hourra, they provide everything, inlcuding formula. So yay!</p>

<p>it was in on the frq two years ago.</p>