AP Statistics Post-Exam Details

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Our current plan for the last four weeks of classes can be found here: Post-exam/Final Project Schedule. Most of this time will be spent working on final projects, but we have some other tasks schedule as well, including a discussion of strategies for getting college credit for this course and learning about one last type of statistical inference!

Also, as posted before, you can review the questions from this year’s AP Statistics exam here and my responses here. Disclaimer: this is my own work, based on my own understanding of the questions. I do not guarantee that all responses would be awarded full credit (though I usually do fairly well!). Moreover, I tend to be very thorough with my responses, more than the AP rubrics generally require (especially with the hypothesis test question). Do not be nervous if you did not give quite as much detail as me.

 

AP Statistics Free Response Questions Posted!

You can review the questions from this year’s AP Statistics exam here. My responses are here. Disclaimer: this is my own work, based on my own understanding of the questions. I do not guarantee that all responses would be awarded full credit (though I usually do fairly well!). Moreover, I tend to be very thorough with my responses, more than the AP rubrics generally require (especially with the hypothesis test question). Do not be nervous if you did not give quite as much detail as me.

AP Statistics Exam Final Thoughts

Your AP Statistics Test is Thursday afternoon. Be outside York Lecture Hall by 11:50 with your calculator and pencils (non-mechanical, remember!). Do not bring your backpack, bag, or your cell phone (or any other “smart” device like watches); find somewhere to put them. You may bring a snack or water, but it must be in clear packaging and you may not have it at your desk with you. Do not expect to leave until at least 4:00!

See this post from before with the archive of review materials.

Things you should be sure to remember (these are my thoughts, see pages 608-610 of your review book for some further points):

  • The formulas for the mean/standard deviation of a sampling distribution of means and a sampling distribution of proportions are on your formula sheet. Whenever you’re being asked to calculate a mean or a standard deviation, check to see if it’s one of these.
    • Related: Pay attention to which standard deviation you are being asked to calculate. The standard deviation of a sample is not the same thing as the standard deviation of a sampling distribution.
  • Probability questions will come in three categories
    • Direct calculation based on a finite sample space (like rolling dice). Write out all the possible outcomes and count which ones are the ones you want. This also includes two-way tables. Don’t try to use fancy formulas for those; just count!
    • Number of successes questions. For example: “how many model E cars would you expect to see in a 2000 car sample?” or “what’s the probability that at least one out of the four drivers is speeding?” These are applications of the binomial probability model and should be calculated appropriately using the formulas on your sheet.
    • Number of trials questions. For example: “how many chips would you expect to need to check before finding a defective one?” or “what’s the probability that the 5th donor is the first with Type-B blood?” These are applications of the geometric probability model. The formulas are not on your sheet, and so you should memorize them: q^(K-1)*p for a general probability and 1/p for the expected value.
  • Know how to combine the standard deviations of two or more random variables. Remember: variances always add.
  • Know how to read the regression output of a linear association. What do “constant,” “estimate/coefficient,” “prob” all mean? Refer to pages 111-112 in your review book or page 729 in your textbook.
  • Know the difference between stratified and cluster sampling and how to identify/use them. Also remember that for a simple random sample every possible sample has the same chance of being chosen.
  • Know the important conditions for each of the inference procedures:
    • Everything: Random Condition
    • Any z-test: Success/failure condition
    • Any t-test: Nearly Normal/Large Enough condition
    • Any chi-square test: Expected cell frequency condition
    • Any 2-sample/2-proportion test: groups are independent from each other.
    • Also: know when to use a 2-sample t-test vs. a matched pairs t-test
  • Be mindful of notation. Don’t use x-bar when you should be using µ. Don’t use p when you should use p-hat.
    • Related: No Naked Numbers! Every number included in any response should have a label somewhere (mean, standard deviation, p-value, etc.)
  • Context, context, context. Always frame your answers in the context of the situation. Don’t say, “I am 95% confident that the true proportion of success is between 22% and 37%.” Say instead: “I am 95% confident that the explosive sensor will accurately detect hidden explosives 22% to 37% of the time.”
  • Be complete with your responses. When choosing between two possibilities in a free response question, explain why one possibility is wrong and why the other one is correct. When asked to compare two distributions, make explicit comparative statements, e.g, “Group 1 is centered at around 12, which is greater than Group 2, which is centered around 7”
  • At the same time, don’t give more information than is requested. If the question asks you to describe the shape of a distribution of data from a histogram, don’t discuss center and spread. If the question asks you to explain your randomization procedure for an experiment, you don’t need to explain what the response variable is, how you’re going to measure it, and what a statistically significant outcome would look like. If the question asks you to merely calculate a confidence interval, you don’t have to interpret it.

AP Statistics Pre-exam breakfast

Ms. Seifert and I would like to invite you to a pre-exam breakfast and review session in her room, H213, on Thursday. We’ll start things up around 8:40 for those of you who don’t have 1st period free, and we’ll spend 1st period hanging out and answering any lingering, last-minute questions you may have.

We plan to get bagels, but if you have dietary restrictions (gluten free, vegan, etc.) please indicate them on this form by the end of the day!

AP Statistics Assignment for Week of 5/13

Your AP exam is on Thursday, in the afternoon. Between now and then, what we do for review is largely up to you. I’ll have some ideas here and there, but I’ll expect you to ask questions and guide what we do for these last few days.

Tonight, you should take a look at the AP Exam tips on pages 608-610. We’ll do some more review with AP multiple choice questions in class tomorrow, but after that it’s up to you!

AP Statistics Assignment for 5/8 & 5/9

By Friday, complete the 2014 released Free Response Questions. On Friday, you’ll get into grading groups and score your peers’ responses according to the scoring rubric. Note that this is a different exam from what appears on your review calendar.

This grade will not be counted towards your marking period average. Please do not review the solutions to these problems. Let this be another opportunity to practice the free response section of the exam. Spend no more than 1.5 hours, and use no resources other than your calculator and formula sheet.

Write all of your answers on blank sheets of paper. More than one solution per page is fine; we’ll staple them together in class. But please make it neat! Your peers will be reviewing your work!

AP Statistics Assignment for 5/7

We reviewed the binomial and geometric probability models today, along with sampling distribution models for proportions and for means. Tonight, please do the following

In addition, I’d recommend you look at section 10 from your review book.

Review my answers here before class tomorrow so we can address any lingering questions you may have more efficiently.

AP Statistics Assignment for 5/6

We did some review of probability today, in particular parts of chapters 14 and 15 of your textbook. Your homework tonight is:

In addition, I’d also recommend you look at Question 3 from the 2008 Free Response, as well as Section 8 of your review book.

Review my answers here before class tomorrow so we can address any lingering questions you may have more efficiently.

AP Statistics Assignment for 5/1

We will have an in-class quiz assignment tomorrow, where I’ll put you in groups and give you an investigative task from a past AP exam to work on. You’ll have the whole period to work on it, but you won’t be allowed to use your notes or text: only your own effort (and the formula sheet).

In preparation, take a look at the Investigative Task section of your review book (Topic 14), then work on questions 1, 3, 6 from problems starting on page 403.

AP Statistics Assignment for 4/30

We reviewed the Linear Regression t-Test, our test for association in quantitative data. Your homework is:

Please review my answers here before class tomorrow so we can more efficiently resolve any lingering questions you may still have, and spend most of the period tomorrow talking about the multiple choice section of the practice AP.

AP Statistics Assignment for 4/29

As we start the next phase of our review for the actual AP exam on May 16, we will be starting with the top two review requests from the survey I ran over the weekend: Unit 7 (Chi-squared and linear regression tests), and Unit 4 (Probability). This review will feature mostly in-class examples and discussion, followed by select AP free response questions as homework. The rough schedule for these next three weeks can be found here.

Today, we reviewed Chi-Square tests. Your homework is:

Please review my answers here before class tomorrow so we can more efficiently resolve any lingering questions you may still have.

AP Statistics Review Information

Key Dates

  • Thursday, April 25, 8:00 am – Practice AP Statistics exam (York Lecture Hall)
  • Thursday, May 16, 12:00 pm – Actual AP Statistics exam (York Lecture Hall)
    • For both exams, bring your calculator and pens/pencils (preferably only pencils, and no mechanical pencils).
    • Do not bring cell phones, backpacks, bags, or any other items. Food and water bottles are permitted, but must be left at the front of the room and can only be accessed during breaks.

Review Materials

Assignment for Spring Break

It’s spring break. We just finished the long walk from February break to April. When we get back, we’ll only have 8 short weeks before the end of the school year. But you have a week to rest and regroup  before we get there. So here’s your assignment for this week:

Stay up until 3am, then sleep in until noon. Read a book. Watch a movie. Make a movie with some friends. Go out at night and ponder the stars. Go for a hike in the Cornell Botanic Gardens. Hang out on The Commons with some friends, then each lunch at Waffle Frolic. Plan a day trip to Syracuse, or NYC. Go to the SPCA and pet the cats (or the dogs!). Listen to some music. Start to learn to play an instrument. Do a barrel roll. Watch the first two episodes of Game of Thrones. Go play in a trivia game at Kilpatricks or Ithaca Bakery. Go for a run before the sun rises. Go for a walk in Stewart Park. Go say hi to Mr. Noyes at the farmer’s market (he sells flowers!). Do some push ups, or pull ups, or squats. Make dinner for your family. Bake something. Go out and do a Random Act of Kindness for a stranger. Hop on the TCAT and just ride around for an hour. Go to a restaurant and order something you’ve never tried before. If you’re in AP Statistics, work out of your review book (Practice Exam 1 would be a good choice!).  Go out and practice some rock balancing. Play a board game. Learn a card trick. Start a YouTube channel. Take some pictures, but don’t show them to anybody. Do your chores. Do someone else’s chores. Talk to someone with different opinions from you. Go to somewhere in Ithaca you’ve never been to before. Whatever you do, enjoy yourself and find some time to relax. Then come back on the 22nd ready to work.

AP Statistics Review Phase 1

Our review for the AP Exam has started. Phase 1 will take us to the practice AP exam on Thursday, April 25th at 8:00 am in York Lecture Hall. More details will be posted soon.

The review calendar for the first part can be found here. Most of this review will be done out of the Barron’s review books you have obtained, so plan on bringing those to class for the first several days of review. There is a lot more to these books than we plan to do in class, so please continue to work through the practice tests and other chapters on your own.