Official 2020 AP Stats Exam College Board Lesson #3 Confidence Intervals for Means (SPDC) 4_8_2020

Hi all!  It came through!! 😊

That was a great lesson from Luke Wilcox!  Here are my take-aways and teacher comments:

Reminders

• 4 weeks of lessons and preparation for the exam is being taught/reviewed (recorded) M-F: 2-2:45 PM in these YouTube Lessons 😊  https://www.youtube.com/watch?v=ChEJ2aRVo5E&list=PLoGgviqq4845u-QDW3bikMhC4uQsuYDpy&index=11

• Lessons: April 6-10: Units 6-7 taught first because many schools either didn’t get to these entirely or at all (we did get through most of this); April 13-May 1: Units 1-5
• AP Stats Exam Friday May 22 from 2-2:45 EST
• All resources available at Statsmedic.com/youtube
• If you need a device take the Exam go to cb.org/tech

Example 1 “Average preparation time for the AP Stats Exam” constructing a 1 mean confidence interval (4 step SPDC process) TPS section 8-3

• The name of the procedure is what we call the Inference Method (IM) T-Interval
• We remember the conditions by using the acronym Random Normal Independence (RNI)
• You can state something like we will assume that there are at least 200 AP Stats students in the testing population as your Independence step as we do in class instead of the way Luke Wilcox does it
• You must state df = 19 somewhere in your 4 step process
• You can report all of the data from your calculator function Stat à Test  8: T-Interval  in the Do step:  Notice that he clearly states that is what is needed, look at his rubric 😊
• You can use 2^nd àVars 4: InvT (0.05/2, 19) MAKE IT POSITIVE to get z* = 2.093 instead of the T-Table as we did in class

Example 2 “Average preparation time for the AP Stats Exam versus the AP Calc Exam” constructing a 2 means difference confidence interval (4 step SPDC process) TPS section 10-2

• The name of the procedure is what we call the Inference Method (IM) 2 Samp T-Int
• We remember the conditions by using the acronym Random Normal Independence (RNI)
• You can state something like we will assume that there are at least 200 AP Stats students and 400 AP Calc in the testing population as your Independence step as we do in class instead of the way Luke Wilcox does it
• You must state df = 31.24 (it’s easier to me to use this df value because you copy it right off of your  calculator in the Do step--next bullet, less thinking involved)
• You can report all of the data from your calculator function Stat à Test  0: 2 Samp T-Int  in the Do step:  Notice that he clearly states that is what is needed, let the calculator technology help you out 😊
• You can just write t* and no value if you copy the df = 31.24 from the data from Test  0: 2 Samp T-Int
• The last question highlights the connection to a test in section 9-3 where zero NOT in the interval leads to  “Reject the Null Hypothesis” since the statement of no (zero) difference is NOT supported 😊

If you can, do the homework each day (or watch the recoding at you leisure) and follow along as we learn.

As always please email me with questions, comments, thoughts.

Take care!