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Thursday, February 28, 2019

If you were absent yesterday and/or today you must make up your CI (ch. 19) quiz and/or your Ch. 19 Vocab Quiz--these must be completed by the end of the day Monday! 

Thursday's HW = Intro to Hyp. Tests....
  • Page 469: 1, 2, 7, 11a
    • For 1, 2, and 11a it's all about writing hypotheses--practice from today's notes
    • For #7 start by finding some probabilities--this question is all about thinking and coming up with ideas, not "right answers."
      • For 7a, what is the probability you lose two times in a row with a coin flip? If you lose two times in a row do you think this friend can control the outcome? 
      • What's the probability you lose 3 times in a row? (7b)
      • Are you now convinced, after 3 losses in a row, that your friend is controlling the outcome of the coin flip? Why or why not? (7c)
      • And for 7d, just think about some probabilities here--there aren't any right answers, just come up with some ideas!

Today's Class Recap:
  • First 10 min = ch. 19 vocab quiz
  • Ch. 20 Notes:
    • Hypothesis Testing: what is the process (4 steps)
      • Outlined the process for any hyp. test problem
    • Writing Hypotheses:
      • Read pages 454 (A Trial As A Hypothesis Test) and 456 (1. Hypotheses), then look at the step-by-step example at the bottom of page 459 or bottom of p. 463 to catch up on this stuff!
      • And/or get someone's notes from today--this stuff is a big deal!
      • What is the null hypothesis? Alternative hypothesis?
        • How can we view a courtroom trial as a hypothesis test--how would we define the null and alternative hypotheses? 
      • How do we write the null and alternative hypotheses using correct mathematical notation?
      • Practice Writing Hypotheses....
        • Wrote null, alternative for our "cereal" slide from last night's homework
        • Also wrote hypotheses for the two contexts on the "Writing Hypotheses" slide (and glued it in)

Tomorrow we'll get back to our notes on hypothesis testing and start to discuss the conditions and math(ematical logic) behind this stuff. Then, Monday and Tuesday we'll wrap up with our conclusion and some more details!

Wednesday, February 27, 2019

Wednesday = 2 HW Responsibilities

If you were absent today you must make up your CI (ch. 19) quiz tomorrow or Friday during lunch, study hall, or after school either day (it's a 30 min quiz).

And if you were out today come ready--YOU WILL BE TAKING THE VOCAB QUIZ tomorrow! No excuses!

Tonight you have two things to get done....

1.) Based on today's "cereal" context: Please create a confidence interval (full process: conditions, math, interpret) AND then USE the interval to determine if the interval supports the students' belief that the proportion of boxes with vouchers is less than 0.2.


  • Do this in your notes (with the slide we glued in today)
  • If you were out, here's the context (and directions):



2.) STUDY! Tomorrow we'll start class with a chapter 19 vocab quiz. Here's the list:

  • Confidence Interval (what is it used for? why do we create a confidence interval?)
  • Sample Statistic
  • Population Parameter
  • Randomization condition: WHY do we check this? 
  • 10% condition: WHY do we check this? .
  • Success/Failure condition: WHY do we check this? 
  • Critical Value
  • Margin of Error
  • Point Estimate
  • Meaning of ___% Confident (Interpret C. Level)
  • Know how increasing/decreasing sample size affects ME and the width of an interval
  • Know how increasing/decreasing C. Level affects ME and the width of an interval
  • What determines the "one" in "one proportion z interval?" (it's "one" because there's one sample of data!)
  • Standard Error
    • An estimated standard deviation calculated using sample statistics
    • Standard error means the same thing as standard deviation; it's still a measure of spread, but it's technically called a standard error if we have to use p-hat in the formula instead of p
      • So, when we show the work for a confidence interval formula, technically we're showing a standard error under the square root, not a standard deviation

Today's Class Recap:
  • First 30 min = ch. 19 quiz
  • Got new ch. 20 slides and cut out first slide (see image above)
    • Discussed how we can address this question using a CI (our hw is to actually do this, see above)

Tuesday, February 26, 2019

BIG Quiz Tomorrow!

Tomorrow we will start class with a 25ish minute quiz on chapter 19--this quiz will be worth more points than any so far this quarter, so come ready!

  • Tonight, finish 2010 #4 AND score it as a way to review!
  • What should I use to study?
    • Pay a little extra attention to "interpreting confidence level," only because today was the first time we have practiced that--see the extra practice below
    • Today's classwork, completed and scored
    • Last night's homework (lots of math stuff)
    • Your take home quiz from our long weekend (passed back yesterday)
    • Your notes
    • AP Stat Guy videos
    • Want some more practice? Try any/some/all of these (and check in the back of the book)
      • Page 446-449: 3 (conditions), 13c, 21c, 23d (interpret C. level), , 25 (create and use interval), 29ab (create interval, know how changing n affects ME), 33 (find n), 
Anything confidence intervals is free game for tomorrow...just be ready for it all...


  • What do I need to know about confidence intervals?
    • When/why do we create a confidence interval?
    • What symbol is a sample proportion/%? A population proportion %? (statistic v. parameter)
    • How do we identify/calculate x, n, and p-hat for a given context? 
    • What wording in a question suggests I have to create a CI?
    • How do I find the critical value for a given C. Level using...
      • t-table 
      • invnorm(
    • What is the full CI process?
      • How do I check conditions for a one prop z interval?
      • How do I do the math with my calculator and show the supporting formula? 
      • How do we interpret the meaning of a confidence interval?
    • How can we use our confidence intervals to assess some claim? (like 13d from the weekend hw)
    • What is ME? 
    • How can we calculate margin of error given a sample size, C. Level, and p-hat? 
    • How can we calculate sample size for a given ME?
    • How does changing n affect the ME? the width of an interval?
    • How does changing C. Level (and as a result, z*) affect the ME? the width of an interval?
    • How can we find the value of p-hat (a point estimate) only given an interval? 
    • How can we find the ME only given an interval? 
    • What does it mean to say "__% confident?"--how can we interpret the meaning of a confidence level? 
  • If you have any questions, things you're confused about, or just want a deeper understanding, take the time this weekend to use your resources!
    • Watch AP Stat Guy videos 6-9 in Unit 5 for some help!
    • Use Khan Academy--this is aligned with AP Stat!
      • Linked on the right WITH a course code
    • Google stuff--anything about one proportion z intervals!

Today's Class Recap:
  • Today was all practice!
  • Stamp = Classwork Grade (3 MC) 
  • Completed 2010 AP FR #3 in groups (14 min)
    • Interpret C. Level, use an interval to test a claim, find sample size
  • Scored a classmate's FR using the rubric, discussed
  • Completed 2010 AP FR #4
    • Create and interpret interval (don't forget conditions)!, know why we check 10% condition...

Tomorrow (after our quiz) we'll start talking about hypothesis testing--see you there!

Monday, February 25, 2019

Monday HW!

Monday HW: Tonight please complete the "packet" provided in class (or below). 

  • An answer key for tonight's hw is also posted below. 





Today's Class Recap:
  • Stamp = finding our sample statistic and ME given only the interval
  • HW Q's: #8 and 38a discussed in class, also addressed any other HW q's
    • Be sure to check the conditions for any "full interval" question (like 13
  • Ch. 19 Notes: 
    • What is a point estimate
    • How can we find ME and a point estimate given only a confidence interval? ("top right slide")
    • What is the meaning of the confidence level?---how can we interpret a given confidence level?
  • Tuesday: ch. 19 practice (AP FR and MC)
  • Wednesday: goal = ch.19 quiz on this day, then intro to ch. 20 (hypothesis testing)
  • Thursday and Friday: ch. 20 notes (one proportion z tests)

Monday HW Answer Key:
  • 1 (Finding sample size; A state's dep't of education....): n = 179 applications
  • 2 (find point estimate and ME given a CI; A sales company....): 
    • a.) 90.5% = 0.905 = p-hat
    • b.) 4.5% = 0.045 = ME
  • 1 (How often do Americans dine out?)
    • a.) p-hat = 0.18 = 18%
    • b.) ME = 0.04 = 4%
  • 2 (A poll of 2,017 likely voters...) 
    • C Level = 95% (z* = 1.96)
  • 3 (A survey found that 69%...)
    • ME = 2.38%
  • 4 (A study was recently conducted...)
    • Interval = 67.5% to 72.5%


Self-Assess Your Understanding of Confidence Intervals!
  • It is absolutely essential that you make sure you're on top of all this interval stuff--not only do we have a quiz on Wednesday, but we also know that these concepts will be repeated multiple times over the remainder of AP Stat!
  • What do I need to know about confidence intervals?
    • When/why do we create a confidence interval?
    • What symbol is a sample proportion/%? A population proportion %? (statistic v. parameter)
    • How do we identify/calculate x, n, and p-hat for a given context? 
    • What wording in a question suggests I have to create a CI?
    • How do I find the critical value for a given C. Level using...
      • t-table 
      • invnorm(
    • What is the full CI process?
      • How do I check conditions for a one prop z interval?
      • How do I do the math with my calculator and show the supporting formula? 
      • How do we interpret the meaning of a confidence interval?
    • How can we use our confidence intervals to assess some claim? (like 13d from the weekend hw)
    • What is ME? 
    • How can we calculate margin of error given a sample size, C. Level, and p-hat? 
    • How can we calculate sample size for a given ME?
    • How does changing n affect the ME? the width of an interval?
    • How does changing C. Level (and as a result, z*) affect the ME? the width of an interval?
    • How can we find the value of p-hat (a point estimate) only given an interval? 
    • How can we find the ME only given an interval? 
    • What does it mean to say "__% confident?"--how can we interpret the meaning of a confidence level? 
  • If you have any questions, things you're confused about, or just want a deeper understanding, take the time this weekend to use your resources!
    • Watch AP Stat Guy videos 6-9 in Unit 5 for some help!
    • Use Khan Academy--this is aligned with AP Stat!
      • Linked on the right WITH a course code
    • Google stuff--anything about one proportion z intervals!
  • Do this now! If you try to assess your own learning this weekend, then you have Monday/Tuesday to come see me for any help before our quiz--don't wait until it's too late?




Friday, February 22, 2019

Fri-yay!

Responsibility #1: Weekend HW 
  • Pages 446-448: 7, 8, 13abd, 27a, 31ac, 35, 38a
    • For 7,8: when it says, "for a given" or "for a fixed" or "for a specified" it means that values is staying the same...
      • So "for a given sample size," means, if n stays the same, "reducing ME will mean lower confidence"--T or F? (that's #8 a)
    • For 13a DON'T FORGET CONDITIONS!
    • For 27a consider the sample size(s)...
    • For 31ac....use today's notes/example from class!
      • What do you notice--how much larger of a sample did we need to cut the margin of error in half (from 6% to 3%)?
      • How could you have answered (c) without using the "finding n" formula?
    • For 35, more finding n--use today's notes/examples!
    • For 38a, "explain why the poll is actually inconclusive" means "explain why we cannot conclude that the amendment will win" (based on this poll and confidence interval) 

Responsibility #2 = Self-Assess Your Understanding of Confidence Intervals?
  • It is absolutely essential that you make sure you're on top of all this interval stuff--not only do we have a quiz on Wednesday, but we also know that these concepts will be repeated multiple times over the remainder of AP Stat!
  • What do I need to know about confidence intervals?
    • When/why do we create a confidence interval?
    • What symbol is a sample proportion/%? A population proportion %? (statistic v. parameter)
    • How do we identify/calculate x, n, and p-hat for a given context? 
    • What wording in a question suggests I have to create a CI?
    • How do I find the critical value for a given C. Level using...
      • t-table 
      • invnorm(
    • What is the full CI process?
      • How do I check conditions for a one prop z interval?
      • How do I do the math with my calculator and show the supporting formula? 
      • How do we interpret the meaning of a confidence interval?
    • How can we use our confidence intervals to assess some claim? (like 13d from the weekend hw)
    • What is ME? 
    • How can we calculate margin of error given a sample size, C. Level, and p-hat? 
    • How can we calculate sample size for a given ME?
    • How does changing n affect the ME? the width of an interval?
    • How does changing C. Level (and as a result, z*) affect the ME? the width of an interval?
    • How can we find the value of p-hat (a point estimate) only given an interval? (Monday's class)
    • How can we find the ME only given an interval? (Monday's class)
    • What does it mean to say "__% confident?"--how can we interpret the meaning of a confidence level? (Monday's class)
  • If you have any questions, things you're confused about, or just want a deeper understanding, take the time this weekend to use your resources!
    • Watch AP Stat Guy videos 6-9 in Unit 5 for some help!
    • Use Khan Academy--this is aligned with AP Stat!
      • Linked on the right WITH a course code
    • Google stuff--anything about one proportion z intervals!
  • Do this now! If you try to assess your own learning this weekend, then you have Monday/Tuesday to come see me for any help before our quiz--don't wait until it's too late?
Responsibility #3: Catch up on HW!

  • I will accept any/all chapter 19 (confidence interval) HW for full credit on Monday
  • You'll have to come show me before school/after school/during study hall if I don't have time to check in class....
  • Check PowerSchool to see if you're missing anything or have only partial credit (all grades are up to date)
  • AFTER MONDAY I WILL NOT ACCEPT ANY MORE LATE HW!



Today's Class Recap:
  • Stamp = finding n multiple choice
  • HW Q's: #37 and #11
    • Be sure to check the conditions for any "full interval" question (like last night's slide)
  • Ch. 19 Notes: 
    • How can we use a given ME to find sample size? (bottom right slide)
      • Solving an equation!
    • How does changing sample size and confidence level affect...
      • Margin of error?
      • the width of an interval?
      • (Created a table in our notes to summarize this info)

Next Week's Plan:
  • Monday: finish ch. 19 notes
    • Stamp = T/F (like 7, 8 from hw)
    • What is a point estimate?
    • How can we find the value of a point estimate and the margin of error only given an interval?
    • What does the confidence level actually mean?
  • Tuesday: finish any ch. 19 notes (if necessary), ch. 19 practice (FR?)
  • Wednesday: goal = ch. 19 quiz on this day, then intro to ch. 20 (hypothesis testing)
  • Thursday and Friday: ch. 20 notes (one proportion z tests)

Thursday, February 21, 2019

Thursday HW

Tonight you have two responsibilities for HW:

1.) Complete the "bottom left slide" provided in class today (or below)--this was posted yesterday, so you may have it done already! If so, nice job!
  • FULL interval process (conditions, math = calculator screen and formula, interpret interval)
2.) Please also complete the following in your textbook:

Pages 446-448: 11, 37
  • For 11b don't stress too much, try to explain what ME means and then use the answer in the back of the book to help you understand this idea
  • The concept in 11e will be one of the main concepts we address in class tomorrow--you got this!
  • For 37--more math! All math here! Set up a formula using the given margin of error, solve for z*, and then use this to determine the confidence level!
    • C. Level = normalcdf(-z*, +z*, 0, 1)

Weekend HW (if you want to get a head start)!
  • Pages 446-448: 7, 8, 13abd, 27a, 31ac, 33, 37, 38a
    • For 31ac....
      • What do you notice--how much larger of a sample did we need to cut the margin of error in half (from 6% to 3%)?
      • How could you have answered (c) without using the "finding n" formula?
    • For 38a, "explain why the poll is actually inconclusive" means "explain why we cannot conclude that the amendment will win" (based on this poll and confidence interval)
Today's Class Recap (stupid delay shortening class):
  • Stamp = pop classwork assignment! (if you were out today you will do this tomorrow)
  • Ch. 19 Notes: the CI formula and the AP formula sheet
  • Margin of Error
    • How do we calculate margin of error (ME)? (middle left slide)
    • What is margin of error? (definition)
    • How can we use a given sample statistic and ME to create a confidence interval?
  • Intro to Finding N
    • How can we use a given ME to find sample size? (bottom right slide)

"Bottom Left Slide" (tonight's HW) Answer Key:
  • Conditions:
    • We will assume this is a random sample of 2,002 25-32 year old Americans.
    • 2,002 is less than 10 % of all 25-32 year old Americans
    • (2002)(0.53) > 10   and   (2002)(0.47) > 10
    • A one proportion z-interval is appropriate.
  • Math:
    • One Prop Z Int:
      • (0.50124, 0.5587) = 0.53 +/- 2.576 sqrt(0.53 x 0.47 / 2002)
      • p-hat = 0.53
      • n = 2,002
      • x = (0.53)(2002) =1061
  • Interpret:
    • We are 99% confident that the true percentage of all employed 25-32 year old Americans with a bachelor's degree who are "very satisfied" with their current job falls between 50.124% and 55.87% based on this sample of 2002 25-32 year olds. 

Wednesday, February 20, 2019

Tonight please complete the "AP Stat Stamp" worksheet (but it's not really a stamp) about the % of females in the labor force (provided in class or below). 

  • Be sure to complete the full process! Conditions, math, interpret your interval
  • Use 95% confidence (so we all get the same answers)
  • Write everything/show all work as you would on the AP exam to earn (full) hw credit!

If you feel like getting ahead, at some point we will have the problem below for homework--go ahead and complete this on separate paper if you like!
  • If for some reason we did not have this as homework I will count it as extra credit...

Today's Class Recap:
  • Stamp = creating a confidence interval! (math and interpret)
    • Went over stamp
    • How do we show the "math" work on the AP exam (with the CI formula)?
  • Ch. 19 Notes: the CI formula and critical values
    • What is a critical value (z*)?
    • How do we find the value of z* for a given confidence level using....
      • invnorm
      • T-table (provided in class)
    • How is a confidence interval calculated? (breaking down the formula)
      • Connect to formula sheet
      • What is margin of error?


Friday, February 15, 2019

4 Day WkNd!

First and foremost, enjoy your loooong weekend! Take some time to relax, definitely do something fun, spend some time with friends/family, and also enjoy some time to yourself! Recharge those batteries because when we come back we have a looooong stretch of 5 day weeks up to April break, and this is the most critical time in AP Stat (for our exam preparation)!

This weekend you have a few responsibilities:

1.) Please complete the take home quiz provided in class (or below).

  • Be sure to show ALL work for any question with a ** or you won't earn credit!
  • For multiple choice #'s 5 and 7 you have to choose the correct formula for the one proportion z interval--this is based on today's work to develop that formula!
    • For #7 you might need some help finding the "z*" or "critical value..."
    • Extra Stamp Opportunity:
      • Google "critical value" or "z*" and either do some reading or watch some video(s) about what this value is and how it is calculated/found
      • Take notes! 
      • You can earn up to 4 extra stamps depending on the level of detail in your notes--I'll collect these on Weds. (only Weds)
  • Use your notes!

2.) If you did not do either hw from chapter 19 I will accept either/both for full credit on Wednesday!
  • Both assignments are in the textbook--look at the blog posts from Weds. and Thurs. for the problems/directions
3.) Want to get ahead? Learn more about one proportion z intervals?
  • Go to the AP Stat Guy videos (linked below or on the right)
  • Look at Unit 5, Video #'s 6, 7, 8, or 9
    • All of these videos deal with confidence intervals for proportions--some of them recap what we've learned, some will give you some insight into what's coming next!
    • AP Stat Guy Videos! Click me!
Today's Class Recap:

  • Stamp = x, n, and p-hat and conditions review (questions 1 and 2 from the "Investigating Confidence Intervals" activity)
  • Worked in groups to develop the formula for a one-proportion z interval by completing the "Investigating Confidence Intervals" assignment
  • If you were out this is below--do it so you're caught up!
    • Use the example I passed out Monday of the 68/95/99.7 rule to help with #3
    • #3 is the key to completing the rest--we're trying to figure out how an interval is calculated!


What's happening when we come back?
  • When we return we'll spend some time breaking down the formula (that we developed today) more, with the following objectives for learning:
    • Understanding the formula, why it looks the way it does, and how we can apply this same idea to means
    • What is a critical value? How can we calculate (or look up) our critical values?
    • How do we complete a "full" AP free response with confidence intervals? (practice)
    • How can we calculate margin of error?
    • How can we find sample size if we are given a margin of error?
    • How can we find our point estimate and margin of error if we are only given an interval?
      • What is a point estimate?
    • How does changing sample size and/or our confidence level affect the margin of error? the width of an interval?
    • Let's practice all that?
Here is the take home quiz in case you lost yours or were absent:







Thursday, February 14, 2019

Thursday HW!

To all Juniors:
  • Tomorrow we will work (in groups) in class to develop the formula for a one-proportion z interval. Please stop by to grab this assignment/investigation if you have not done so.
    • You should complete this assignment over your long weekend
    • Watch videos about the formula for a one proportion z interval if you need some more help/explanation!
    • You will be responsible for knowing/understanding this stuff--the more effort you put into the classwork you missed, the better prepared you will be!
    • Please get a copy of the notes from a classmate as well!
  • Over the long weekend we have an assignment that I may collect and grade as a take home quiz. Please stop by tomorrow morning for a copy if you do not have one already.
  • Another option: Juniors, if you would like, please feel free to attend period H (AP Stat) tomorrow. You are scheduled to have lunch at 11:35 to 2:10, which is H period. Of course if you're hungry and tired after a long day then EAT! Don't feel obligated, but this is an option for you. 

Thursday HW: 
  • Pages 446-448: 5, 9, 21ab, 23bc
    • For 5 your job is to determine which of the interpretations is correct, if any, and provide a bullet explaining why (like today's slide)
    • For #9 interpret the given confidence interval!
    • For 21a use your calculator to find the interval and copy your calculator screen as your math work, then interpret your interval for part b
      • Please also write down the values of x, n, and p-hat
    • For 23bc, same--part b = math = calculator screen, c = interpret
      • Please also write down the values of x, n, and p-hat
    • *Remember to always round n to the nearest whole number or you'll get an error on your calculator!
Today's Class Recap:
  • Stamp = x, n, and p-hat
  • Ch. 19 Notes
    • What is the process for any confidence interval question?
      • Conditions: what are they?
        • Discussed a "tweak" for the success/failure condition
      • Math: what do we show? 
        • Also added notes on n, x, and p-hat
      • Interpret 
        • How do we interpret a confidence interval? 
        • Provided a template for interpreting intervals in our notes
    • Interpreted an interval and identified x, n, p-hat in our notes for a given context (3 slides given yesterday)
    • Then, discussed which interpretation (also in those 3 slides) a-e was correct and what issues there were with the incorrect interpretations
    • Learned how to create a one proportion z interval using our graphing calculator (tomorrow we'll investigate this formula)


Wednesday, February 13, 2019

Wednesday HW!

**If you were absent today you must make up your chapter 18 vocab quiz before the weekend! And be sure to bring your take home quiz in tomorrow!**

Tonight please complete the following in your textbook--use the instructions below (some are changed from the book)!

  • Here's some stuff you need for tonight's homework before you start: 
    • n = sample size (will be given in the question/context)           
    • x = # of "successes" in a sample
      • x = (n)(p-hat)              
    • p-hat = % of "successes" in our sample
      • p-hat = x/n
    • Sometimes our question/context gives us p-hat and n, sometimes it gives us x and n; we have to know how to find each of these three values (x, n, and p-hat) in either scenario (both situations come up in this hw)
  • Pages 446-449: (answers are posted below)
    • 15 (For this question please simply provide the values of x, n, and p-hat.)
      • Hint: x and n are given, you have to find p-hat....
    • 21 (For this context provide the values of x, n, and p-hat AND check if the conditions for a one proportion z-interval are met)
      • Hint: this time, p-hat and n are given, and you have to find x!
      • Remember, when checking the conditions, we must use p-hat for our "success/failure" condition because we don't know the value of p
    • 23a (For this question/context please verify that the conditions for a one proportion z-interval are met)
      • Hint: in this context the values of x and n are given, you have to calculate p-hat
  • Stamp for Tomorrow: (look up) and record the definition of statistical inference in your notes
Today's Class Recap:
  • Chapter 18 Vocab (and conditions) Quiz = 13 min
  • Ch. 19 Intro Notes
    • Why do we use a confidence interval?
    • What is a one-proportion z-interval?
    • What is the process for any confidence interval question?
      • Conditions: what are they?
        • Discussed a "tweak" for the success/failure condition
      • Math: what do we show? (Thurs)
        • Also added notes on n, x, and p-hat
      • Interpret (Thurs)
        • How do we interpret a confidence interval? 
        • Provided a template for interpreting intervals in our notes

HW Answer Key (for tonight's hw):
  • 15.) n = 122, x = 78, p-hat = 78/122 = 63.934%
  • 21.) 
    • n = 2700, p-hat = 0.20 (or 20%), x = (0.20)(2700) =540
    • This is a random sample of children (randomly selected from all parts of England)
    • 2700 is most likely less than 10% of all children in England
    • (2700)(0.20) > 10 and (2700)(0.80) > 10
    • A one proportion z interval is appropriate.
  • 23a.)  A one proportion z interval is appropriate because:
    • This is a "random survey of 226 college students."
    • 226 is less than 10% of all college students
    •  (226)(0.0885) > 10 and (226)(1 - 0.0885) >10
      • Note that you can also check this condition without using p-hat...
        • The number of "successes" is 20, which is greater than 10, and the number of "failures" would be 226 - 20 = 206 which is also greater than 10
        • Remember, this condition requires us to check that the number of "success" and the number of "failures" are both greater than 10, and in this case, the number of "successes" (or x) is directly given!
      • Or check using p-hat as shown above!
      • p-hat = 20/226 = 0.0885 (or 8.85%)


Monday, February 11, 2019

Take Home Quiz and Vocab Quiz!

Tonight you have 2 responsibilities:

1.) Complete your take home quiz (see below if you were out)
  • Get this done tonight! Don't wait and hope for a snow day then end up getting a 0! Be responsible!
2.) STUDY--we will start class with our chapter 18 vocab quiz tomorrow (or the next time I see you)!
  • Quiz = 15 matching vocab AND....
  • 2 contexts where you have to determine which condition does not pass....
  • Here's the chapter 18 vocab list:
    • Sampling Distribution
    • Sample Statistic
    • Population Parameter
    • Sampling Variability
    • Sampling Distribution for Means (for what type of data)?
    • Sampling Distribution for Proportions(for what type of data)?
    • Know which conditions we use for each type of sampling distribution
    • 10% Condition: how do we check it and why do we check it?
    • Success/Failure Condition: how do we check it and why do we check it?
    • Randomization condition: how do we check it and why do we check it?
    • Large Enough Sample condition: how do we check it and why do we check it?
    • Standard Error
    • Central Limit Theorem
    • Know how changing sample size affects standard deviation
Here's the take home quiz in case you lost yours or were out:


Today's Class Recap:
  • Stamp = Sampling Distribution Math!
  • Wrapped up  ch. 18 Notes:
    • Definition of a sampling distribution
    • When do we use sampling distribution formulas?
    • Looked at an example of the 68/95/99.7 rule with sampling distributions
    • Discussed/explored how increasing/decreasing n affects standard deviation
      • Also discussed "diminishing returns"
  • Intro to ch. 19 (notes):
    • What is a confidence interval?
    • Why do we use a confidence interval?
    • What are the steps for any confidence interval free response? 

Friday, February 8, 2019

Weekend HW = 2 Tasks...
  • *Chapter 18 Vocab Quiz will start class Tuesday!
  • 1.) Complete the "bottom left slide" examples a and b. 
    • Do the math, show the work, and check your answers below!
    • I would recommend glueing? gluing? in the slide and putting this in your notebook!
    • Answers:
      • a.) 0.9495
      • b.) 0.10565
  • 2.) Page 429-431: 15, 17, 25, 27, 35, 
    • We should first check the conditions for each of these problems--but for this homework you can skip those and focus in on the math (otherwise this would take forever)
    • For #15 we're asked for the probability that the newspaper's sample will predict defeat...
      • This is the same as asking for the probability that the "% of the sample that support the budget is less than 50%" (because if less than half of the people support the budget it will be defeated)
      • Any time we have to find a probability using a "% of a sample" we have to use a sampling distribution!
    • For #17 we want to find the probability that the shipment will be accepted---this is the same as asking if the % of the sample that do not meet the standard is less than 5%!
      • Since we're asked for a probability in regard to the "% of a sample" this is a sampling distribution question!
    • For 25 consider yesterday'sexamples with rainfall amounts--not all parts (a,b,c,d) require the use of a sampling distribution!
      • For 25c it asks you to "define the model"--this simply means to provide the shape, the value of the mean for the sampling distribution, and the value of the standard deviation for the sampling distribution
    • Here's an example to help with the type of math in 15, 17:

On Monday we'll wrap up chapter 18 and "cross our t's and dot our i's" as they say, finishing up with some more vocab and a couple more examples.

Then, on Tuesday we'll start with our chapter 18 vocab quiz before starting our exploration of confidence intervals (can't wait)!

Here's the chapter 18 vocab list so you can start studying:
  • Sampling Distribution
  • Sample Statistic
  • Population Parameter
  • Sampling Variability
  • Sampling Distribution for Means (for what type of data)?
  • Sampling Distribution for Proportions(for what type of data)?
  • Know which conditions we use for each type of sampling distributino
  • 10% Condition: how do we check it and why do we check it?
  • Success/Failure Condition: how do we check it and why do we check it?
  • Randomization condition: how do we check it and why do we check it?
  • Large Enough Sample condition: how do we check it and why do we check it?
  • Standard Error
  • Central Limit Theorem
  • Know how changing sample size affects standard deviation
Have an awesome weekend!