Weekend HW!

This weekend please complete the "Chapter 12 Homework: Identifying Sampling Methods" worksheet provided in class (or below).

• Answers are posted in green below--check!
• On Monday/Tuesday in class we will continue to discuss sampling, sampling methods, and examine population parameters vs. sample statistics
• The seven sampling methods we saw today are seven new vocab words for chapter 12!
• This homework assignment extends our learning from today's classwork...
• Use the notes/definitions provided in today's investigation to help with your homework.
• See below for an example of a procedure for each sampling method using a different context (you'll get a paper copy of this on Monday).

Here are some examples of procedures for each sampling method using a different context:

Simple Random Sample:

Context: The town of East Hartford is interested in surveying its adult (age 18+) residents about various topics.  You have been hired to choose a sample of 500 East Hartford residents to be surveyed.

Example:

1.      Number each EH adult resident from 1 to _____.

2.      Use a random number generator to generate 500 numbers between 1 and____, ignoring repeated numbers.

3.      Survey the 500 adult EH residents whose numbers were randomly selected.

Census

Context: The town of East Hartford is interested in surveying its adult (age 18+) residents about various topics.  You have been hired to choose a sample of 500 East Hartford residents to be surveyed.

Example: Mail each adult resident (age 18+) in the town of East Hartford a survey asking questions about the desired topics, and ask each person to complete the survey questions and return the form. You may also provide a link to an online version of the survey for people to complete.

For those residents who do not complete the survey (by mail or online), follow up with a phone call. For those who still do not respond, send a town official door-to-door to collect survey responses from the remaining adult EH residents.

Stratified Random Sample

Context: The town of East Hartford is interested in surveying its adult (age 18+) residents about various topics.  You have been hired to choose a sample of 500 East Hartford residents to be surveyed.

Example: You believe that people’s responses to these questions may differ by age group; therefore, you first separate all EH residents into groups based on age (stratify).

1.      First, you create (5) groups of residents ages 18-30, 31-45, 46-60, 60-75, and 75+. (This means we stratified by age group).

2.      Next, we use a random number generator to randomly generate the social security numbers of 100 residents within the 18-24 age group. Ignore any repeated numbers.

3.      We then survey these randomly selected residents by mail (also providing a link to an online survey), then by phone (if they do not respond initially).

4.      Repeat this process for each age group, randomly generating social security numbers (ignoring repeats) to select a random sample from each strata.

*Note: with a stratified sampling method we do not always want to sample the same number from each strata; instead, we want to sample in proportion to our population

·         For example, if 50% of the adult residents in EH were ages 46-60, we would want 50% of our sample to be taken from this age group…

·         We will discuss this more moving forward.

           

Cluster Random Sample

Context: The town of East Hartford is interested in surveying its adult (age 18+) residents about various topics.  You have been hired to choose a sample of 500 East Hartford residents to be surveyed.

Context: The town of East Hartford is interested in surveying its adult (age 18+) residents about various topics.  You have been hired to choose a sample of 500 East Hartford residents to be surveyed.

Example:

1.      First, separate the town into groups (clusters) by elementary school district. (each school district = 1 cluster)

2.      Next, number each school district from 1-8.

3.      Use a random number generator to randomly select two numbers from 1-8, ignoring repeats.

4.      Survey all of the adult residents (age 18+) within those two randomly selected districts.

Systematic Random Sample

Context: The town of East Hartford is interested in surveying its adult (age 18+) residents about various topics.  You have been hired to choose a sample of 500 East Hartford residents to be surveyed.

Example:

1.      Obtain a list of the names of all adult EH residents. List each resident in alphabetical order, by last name.

2.      Number each person on the list from 1 - ___.

3.      Generate a random number to represent your starting point. Survey the resident with that number.

4.      Now, survey every 10^th person on this list starting from the random number generated above.

Voluntary Response Sample

Context: The town of East Hartford is interested in surveying its adult (age 18+) residents about various topics.  You have been hired to choose a sample of 500 East Hartford residents to be surveyed.

Example:

1.      Create an online survey (poll) and post it on the town’s website and each of the school websites.

2.      Mail a letter to each household to make all residents aware that the survey has been posted.

3.      Collect responses (data) from anyone who chooses to go online and complete the survey.

Convenience Sample

Context: The town of East Hartford is interested in surveying its adult (age 18+) residents about various topics.  You have been hired to choose a sample of 500 East Hartford residents to be surveyed.

Example:

1.      Have multiple town officials go to various neighborhoods throughout East Hartford with copies of the survey.

2.      Have these officials administer the survey to any residents who are available or passing by.

OR

1.      The people conducting the study provide the survey to their friends and family and ask them to complete it.

2.      To obtain more data, they stand outside the town hall and/or public library and hand out surveys to those passing by.

And here are the homework answers so you can check:

11a.) Voluntary Response Sample
11b.) Cluster sample
11c.) (Attempted) Census
11d.) Stratified Survey
11e.) SRS (Simple Random Sample)

12a.) Convenience OR Voluntary Response Sample

12b.) Voluntary Response Sample
12c.) Cluster Sample (Maybe stratified by elementary school, then cluster choosing class = multistage)
12d.) Systematic Sample
12e.) Stratified Sample

13a.) Used a combination of stratifying and cluster; first separated into groups (churches) and randomly selected 3 churches (this is a cluster approach), but then selected 100 people from each of these selected churches (stratified approach)--we call this a multi-stage sample

13b.) The 100 members chosen from the 3 randomly selected churches may not be representative of all Catholic church members in this city. 

15a.) Systematic Sample

15b.) This sampple is not likely to be representative of how patrons feel about this ride because every person sampled is in line for this ride, and thus they likely have different opinions about having to wait in line than people who are not riding this ride. This sample is biased, as people willing to wait in line may be overrepresented.

27a.) Simple Random Sample:

• Number the transactions from 1-120.
• Use a random number generator to generate 10 numbers between 1 and 120.
• The supervisor then re-checks the 10 payments with the numbers that were randomly generated.

27b.) I would stratify (by type of sale, wholesale/retail).

• Number the wholesale sales from 1-36.
• Use a random number generator to generate 3 numbers in this range and then re-check these 3 transaction.
• *We choose 3 because we are told 30% of the overall sales are wholesale, so we want 30%, or 3 out of 10, of the sales in our sample to be wholesale so that our sample best represents our population
• Number the retail sales from 1-84.
• Use a random number generator to generate 7 numbers in this range and re-check these 7 retail transactions.

Also, don't forget to reflect and complete the extra credit assignment below--due Monday! 

Extra Credit Homework Assignment: Midterm Exam Reflection Questions:

• These questions can be completed and turned in Monday for EXTRA CREDIT (homework and 2 or 3 stamps). 
• You must write the question OR write the heading bulleted below each question
• No question/heading written, no extra credit
• This will be scored based on you showing real, thoughtful reflection--lazy, quick, one word answers for questions 3-8 will not earn extra credit! Take some time to truly reflect on your exam and on your first semester!
• Examine your score, the histogram, and summary statistics below to answer each question:

1. Record your projected AP score and your raw score below. (You will have to read the information on the blog to determine these).

• Projected AP Score:________              Raw Score:_______%

2. Calculate the z-score for your raw score using the data above. Show your work below.

•  z = ___

3. What are your initial reactions to your individual exam score? Record at least three thoughts in the space below.

•  Initial Reactions: Individual Score

4. Examine the data above; what are two positive things that stand out to you about our overall midterm exam performance?

• 2 Positives: Overall Performance

5. What is something that stands out as an area (or two) for improvement for our overall performance (as a whole group)?

• Area to Improve: Overall Performance

6. What are two things you have done well individually in preparing for success in AP Stat over the course of the first semester?

•  Individual Preparation: 2 Successes

7. What are two things you can improve upon (moving forward) to put yourself in the best position to succeed on the AP exam in May?

• Individual Preparation: Areas to Improve

8. What are two things you learned from the midterm exam that will help you to better prepare for the AP exam (May 17)?

• Midterm to AP Exam: Takeaways

Thursday HW and Stuff

Tonight please complete the "Pop Quiz: Sample Surveys" worksheet provided in class (or below). (It's not really a pop quiz).

• We will have a quiz that looks very much like this to start class one day next week--this is a practice version of that quiz!
• Here is the homework in case you lost yours or were out:

Midterm grades are in! Here's everything you need to know about the midterm scoring:

To score the midterm I first calculated each raw score (%); the multiple choice section had 28 questions for 28 points and counted as 50% of the overall grade. The free response section consisted of 5 questions worth a total of 20 points, and also counted as 50% of the overall grade.

I then used past AP exam "cut scores" to establish the cutoff values for a score of 5, 4, 3, 2, and 1 (see below)--in other words, I figured out which raw scores (%'s) corresponded to which AP scores. Next, I listed each score from greatest to least, and separated the scores (5's, 4's, 3's, etc.)--a projected score of 5 translates to an A, a projected 4 to a B, a projected 3 to a C, a projected 2 to a D, and a projected 1 to an F. Finally, within each AP score/letter grade, I determined a numerical grade equivalent as shown in the chart below.

Students typically performed better on the multiple choice section; overall, we did pretty well with the multiple choice, but definitely will have to make a conscious effort to improve our writing and written communication for the free response section.

The midterm exam will hopefully prove itself to be a valuable learning experience that will help us better prepare for the AP exam; overall, 40/78, or 51.2% percent of students projected to earn a qualifying score (3 or above) on the AP exam.

I will hold on sharing my thoughts, as for homework on Thursday night you will be asked to complete a reflection on the midterm exam. After you develop your own thoughts we will discuss the midterm in more depth on Monday, 1/22.

Here is our midterm exam summary data:

You can use the chart below to determine your raw score from the grade entered in PowerSchool.

Extra Credit Homework Assignment: Midterm Exam Reflection Questions

• These questions can be completed and turned in Monday for EXTRA CREDIT (homework and 2 or 3 stamps). 
• You must write the question OR write the heading bulleted below each question
• No question/heading written, no extra credit
• This will be scored based on you showing real, thoughtful reflection--lazy, quick, one word answers for questions 3-8 will not earn extra credit! Take some time to truly reflect on your exam and on your first semester!

1. Record your projected AP score and your raw score below. (You will have to read the information on the blog to determine these).

• Projected AP Score:________              Raw Score:_______%

2. Calculate the z-score for your raw score using the data above. Show your work below.

•  z = ___

3. What are your initial reactions to your individual exam score? Record at least three thoughts in the space below.

•  Initial Reactions: Individual Score

4. Examine the data above; what are two positive things that stand out to you about our overall midterm exam performance?

• 2 Positives: Overall Performance

5. What is something that stands out as an area (or two) for improvement for our overall performance (as a whole group)?

• Area to Improve: Overall Performance

6. What are two things you have done well individually in preparing for success in AP Stat over the course of the first semester?

•  Individual Preparation: 2 Successes

7. What are two things you can improve upon (moving forward) to put yourself in the best position to succeed on the AP exam in May?

• Individual Preparation: Areas to Improve

8. What are two things you learned from the midterm exam that will help you to better prepare for the AP exam (May 17)?

• Midterm to AP Exam: Takeaways

Midterm Results, Extra Credit HW, Thursday HW!

If we have a snow day use your time productively--get a head start on our new stuff for our new semester by reading chapter 12! The more you read the better prepared you'll be to start out with an A!

• Wednesday/Thursday = Sampling Vocabulary
• Sample, Sampling Frame, Population
• Sample Statistics v. Population Parameters
• Sampling Variability (aka Sampling Error)
• Randomization
• Friday = Sampling Methods
• Simple Random Sample (SRS)
• Census
• Stratified Random Sample
• Cluster Random Sample
• Systematic Sample
• Voluntary Response Sample
• Convenience Sample

If you would like to get a head start here is Thursday night's homework (assuming we have a snow day, if not, this will change)

• We will have a quiz that looks very much like this to start class one day next week--this is a practice version of that quiz!
• Thursday HW:

Midterm grades are in! Here's everything you need to know about the midterm (and your homework due Friday):

To score the midterm I first calculated each raw score (%); the multiple choice section had 28 questions for 28 points and counted as 50% of the overall grade. The free response section consisted of 5 questions worth a total of 20 points, and also counted as 50% of the overall grade.

I then used past AP exam "cut scores" to establish the cutoff values for a score of 5, 4, 3, 2, and 1 (see below)--in other words, I figured out which raw scores (%'s) corresponded to which AP scores. Next, I listed each score from greatest to least, and separated the scores (5's, 4's, 3's, etc.)--a projected score of 5 translates to an A, a projected 4 to a B, a projected 3 to a C, a projected 2 to a D, and a projected 1 to an F. Finally, within each AP score/letter grade, I determined a numerical grade equivalent as shown in the chart below.

Students typically performed better on the multiple choice section; overall, we did pretty well with the multiple choice, but definitely will have to make a conscious effort to improve our writing and written communication for the free response section.

The midterm exam will hopefully prove itself to be a valuable learning experience that will help us better prepare for the AP exam; overall, 40/78, or 51.2% percent of students projected to earn a qualifying score (3 or above) on the AP exam.

I will hold on sharing my thoughts, as for homework on Thursday night you will be asked to complete a reflection on the midterm exam. After you develop your own thoughts we will discuss the midterm in more depth on Monday, 1/22.

Here is our midterm exam summary data:

You can use the chart below to determine your raw score from the grade entered in PowerSchool.

Extra Credit Homework Assignment: Midterm Exam Reflection Questions

• These questions can be completed and turned in Monday for EXTRA CREDIT (homework and 2 stamps). 
• You must write the question OR write the heading bulleted below each question
• No question/heading written, no extra credit

1. Record your projected AP score and your raw score below. (You will have to read the information on the blog to determine these).

• Projected AP Score:________              Raw Score:_______%

2. Calculate the z-score for your raw score using the data above. Show your work below.

•  z = ___

3. What are your initial reactions to your individual exam score? Record at least three thoughts in the space below.

•  Initial Reactions: Individual Score

4. Examine the data above; what are two positive things that stand out to you about our overall midterm exam performance?

• 2 Positives: Overall Performance

5. What is something that stands out as an area (or two) for improvement for our overall performance?

• Area to Improve: Overall Performance

6. What are two things you have done well individually in preparing for success in AP Stat over the course of the first semester?

•  Individual Preparation: 2 Successes

7. What are two things you can improve upon (moving forward) to put yourself in the best position to succeed on the AP exam in May?

• Individual Preparation: Areas to Improve

Midterm Exam Stuff

Let's take this midterm exam as seriously as we intend to take our AP exams; this is a great opportunity to take a shortened practice test and really gauge our progress in preparing for the big day, May 17th. Work hard leading up to the exam and do your best--that's all I ask for, but who cares about me--that's what you should demand of yourself!

If you did not turn in your stamps you must turn them in during exams! Don't get a 0!

Here is a breakdown of the midterm exam:

• Multiple Choice Section
• 60 minutes
• 50% of midterm exam score
• 28 questions
• Free Response Section
• 60 minutes
• 50% of midterm exam score
• 5 questions
• 1 FR: Experimental design (discussed in class)
• 1 FR: Probability 
• 1 FR: Creating Graphical Displays and Summarizing/Comparing Distributions
• 1 FR: Linear Regression
• 1 FR: Use a given graphical display (that you have not necessarily seen) to analyze a context and draw conclusions
• Take a look at FR #1 of the 2015 midterm that was emailed to you
• This type of graph is not on our midterm, but this question challenges you to examine a new type of graphical display and use it to draw conclusions about a context--you will have a similar style question on your midterm

Here are the answer keys for the additional resources provided in class; hints are also provided, as well as some information about the midterm...

USE THIS STUFF! Practice, practice, practice! Also work on the 2015 Midterm that was emailed to you, it's another great resource!

• AP Statistics Midterm Exam: Multiple Choice Extension Questions (hints provided)
• 1.) E
• First, use P(D and E) = .018 and the fact that P(D) = 0.6 to find P(E).
• Then, calculate P(D) or P(E) using this answer
• There are questions calculating "AND" and "OR" type probabilities on the midterm, but entirely in context--there is not a question that is this purely formulaic
• 2.) C
• Which part of the normal model contains the "most" data values? 
• The center is the highest part of the curve, and thus contains the most data--so the interval that contains the greatest proportion will centered around the mean
• OR....
• The "proportion of cartons of large eggs at the store" for each interval would be calculated using normalcdf, but we would need to know the standard deviation to use this--a standard deviation is not given, but we can make one up and use it to test each MC option! 
• I assumed standard deviation = 1 and then used normalcdf to find the proportion of cartons in each interval (a. 0.0228; b. 0.49997; c. 0.9545; d.) 0.4999; e.) 0.0228)
• Be sure to have an understanding of the Normal model for your midterm!
• Know how to use normalcdf to find percentages/probabilities for a Normal model
• Know how to use invnorm( to find data values that represent a given percentile
• Remember how to combine random variables to find a new mean and standard deviation--and then we can apply the Normal model using these values (see #3)
• 3.) B
• First, find the mean, based on rescaling, for 5X - 10Y
• Second, find the standard deviation, based on rescaling, for "5X"
• Now, find the standard deviation, based on rescaling, for "10Y"
• Now, use the idea that "variances always add" to find the standard deviation for 5X - 10Y
• *Note: The "A players total points are calculated as follows: 5X - 10Y" information was not provided in the original question. Examine this expression and re-read the context--how do we arrive at this expression?
• 4.) A
• This question is all about reading carefully
• I would recommend first finding the range for each and using this to narrow down your options
• You can then calculate the median for each (by hand or using your graphing calculator) to decided between A and D
• You may also be able to look at the graph and visually determine that the distribution for females is centered around a higher value
• *You will have to create back to back stemplots the free response section of your midterm
• 5.)  D
• To find the weight, in pounds, at the 75th percentile we could use invnorm(area, mean, st. dev.); next we can see which MC option/expression roughly equals this value
• OR...
• This invnorm( calculation is really based on the z score...
• We know the mean and standard deviation, so if we can figure out what z-score marks the 75th percentile we can substitute that z-score, mean, and standard deviation into the z-score formula and "solve for x"
• This is what our calculator is doing with invnorm(
• To find the z score that marks the 75th percentile we could use a z-table, or we could use invnorm again
• invnorm(0.75, 0, 1)
• .75 is the area to the left or percentile, 0 represents the mean for z-scores, and 1 represents the standard deviation for z-scores
• 6.) E
• Calculate the fences! Check your notes
• And remember, there could still be data values between Q3 and the Max, we just don't know what they are....we don't have that information
• 7.) D
• I used normalcdf( to find the percentile for Aliyaah's height
• We know that the z-score for Aaliyah's height is 0.96 (z-score = the distance from the mean measured in standard deviations)
• So, we'll have to enter a z-score into normalcdf, which means we'll use 0 and 1 for the mean and standard deviation
• We want her percentile, which means we would "shade to the left" if we sketch the model
• normalcdf(-9999999, 0.96, 0, 1) = 0.83
• Now we have each percentile, and we know that Aliyaah is at a lower percentile, which means she is shorter
• 8.) B
• 9.) D
• The median is the middle number--we know each data set has 28 values, and so we know the median is between the 14th and 15th data values (28/2 = 14, median between 14th, 15th data values)
• We can then "count the dots" to find were the 14th/15th data values fall
• We can use the same strategy for Q1 and Q3 (and so, IQR)
• Q1 is the first quartile, so this would be roughly the 7th data value (think: one fourth of 28)
• Q3 is the third quartile, so this would roughly be the 21st data value 
• *Challenge: if Q1 is the same for each, could Q3 be different for this multiple choice question? Why or why not?
• Calculate the range for each
• 10.) D
• We block based on a specific characteristic, like "by the river" and "by the woods," or "room with view" and "no view." 
• We then randomly assign treatments within these blocks
• 11.) A
• Be sure to know what each of our summary statistics actually measures! 
• AP MC WU
• 1.) A
• You could use a tree diagram here
• OR, consider "using words" and substituting probabilities--if people call in sick that means "sunny and call out sick given sunny" OR "not sunny and call out sick given not sunny"
• 2.) C
• Know how mean and median compare based on the shape of a distribution (check your notes!)
• 3.) D
• We can use a Venn diagram or the general addition rule here
• "At least one of the two places" means the person visited the park only, the cave only, or both.
• 4.) E
• Look back at your notes/examples about comparing boxplots!
• AP Stat: Midterm Exam Review (Stamp!)
• 21.) C
• "regression line is an appropriate model"--remember, we want the residual plot to show random scatter
• There are two other conditions to check to determine if a linear model is appropriate--what are they?
• What does a residual plot show us? How could we create residual plot given the original scatterplot and LSRL? How could we re-create the distribution of the points around the LSRL in the original graph given only the residual plot?
• This idea shows up on your midterm!
• Influential Point Question: C
• Check your notes from chapter 9 about outliers, leverage, and influence!
• We have lots of examples like this
• 32a.) predicted final exam score = 63.328 + 2.697(study hours)
• Remember to use a "hat" to show "predicted"
• 32b.) r = 0.753
• Find r from R^2!!
• Always remember to check the slope to determine if r is + or -
• Be sure you know how to do each of the things mentioned in the "Extra Review" list (for regression)!
• Most of these topics appear on your midterm exam, some on the MC, some on the FR
• The World Almanac and Book of Facts Question:
• Should any states be considered outliers? Yes, there is at least one outlier, the maximum of 25.8.
• Calculate the fences! Check your notes!
• Fences = 1.95 and 25.55
• This came up twice in all this review? Must be on the midterm....
• Measures of Center provided: mean, median
• Measures of Spread: standard deviation (IQR, Range can be calculated from the info given)
• Know about the measures of center and spread, and be sure you know how to use "SOCS" to describe a distribution or compare two distributions--this is on the midterm!
• Shape: skewed right 
• Here, the mean greater than the median....
• Know how the mean and median relate based on the shape of a distribution
• Know how measures of center and spread are or are not affected by outliers
• Which measures of center/spread are sensitive to extremes?
• Which are resistant to extremes?
• AP Free Response #1: Comparing Boxplots
• Sample Responses:
• a.) The distributions for the percents of seniors who took the college entrance exam appears roughly symmetric for region I an skewed right for Region II. Region II has one high outlier around 30%, while Region I does not have any outliers. Region I has a much higher median percent of seniors to took the college entrance exam. Region I has a wider IQR and a larger range if we exclude the outlier in Region II, which suggests Region I showed more variability in its percentages (aside from the outlier). Generally, a higher percentage of seniors in Region I took the college entrance exam; in region I, all high schools were above 60%, while in region II only one school was above 15%.  
• You will have to compare two distributions on the midterm exam! Be ready for this!
• First you will have to create the graphical display to use for your comparison: be sure you know how to make histograms, boxplots, and stemplots!
• b.) The histogram of the combined data would be bimodal, with a cluster of data between 0 and 15% (Region I) and another cluster around 60-90% (Region II). There would only be one data value (the outlier in Region I) roughly between 20 and 60%.
• Scoring Rubric:

• AP Stat Mini Test: Geometric and Binomial Probability (from the Friday before winter break)
• 1a.) 0.90
• 1b.) 0.99999
• 1c.) 0.0729
• 1d.) 0.032
• 1e.) P(Sam receives more than 20 flights) = 0.00137
• *Be sure to answer the question and in context! Many people simply provided a number, which is not sufficient
• When taking the midterm exam always re-read the question--and make sure you answered it, in context!
• Midterm Exam Tip: Try to take the wording of the context right out of the given question/info
• Reword the given questions and context to start your responses!
• "I would be surprised if Sam receives more than 20 upgrades because the probability of this occurring is very low.
• OR... 
• "I would be surprised if Sam receives more than 20 upgrades because he is only expected to receive 10.4 upgrades during the year, on average.
• (This type of response would earn partially correct; we would also need to use/reference the standard deviation to complete this logic).
• 2.) B
• 3.) C
• 4.) D
• 5.) E
• 6.) A
• 7.) A
• 8.) B
• 9.) A
• 10.) B
• Experimental Multiple Choice: Experimental Design (went over 1-3 in class today)
• 1.) E
• 2.) E
• 3.) E
• 4.) D
• An experiment is the only method of data collection that allows us to establish a cause and effect relationship!
• 5.) D
• 6.) D
• 7.) D
• Experiments Wrap Up (provided today in class)












• AP Free Response on Midterm:
• Describe a method for randomly assigning treatments, or for randomly assigning treatments within blocks
• Identify factors, levels, treatments, response variable for an experiment
• 2015 Midterm: MC Key
• 1.) C
• 2.) A 
• 3.) E
• 4.) B
• 5.) B
• 6.) D
• 7.) D
• 8.) E
• 9.) D
• 10.) C or D (create a residual plot; if you think it has a pattern the answer is C, if you think this is random scatter it's D--this would be much more clear on our midterm, I stopped using this question for that reason)
• 11.) D
• 12.) D
• 13.) A
• 14.) D
• 15.) E
• 16.) E
• 17.) B
• 18.) B
• 19.) D
• 20.) C
• 21.) B
• 22.) C
• 23.) D
• 24.) D
• 25.) A
• 26.) C
• 27.) E
• I typed this fairly quickly so if you disagree with one of my answers send me a Remind and/or let me know if I made an error! (I don't think I did, but it's always possible!)

Check out the image below for some suggestions about how to study:

Wednesday: 3 Responsibilities

You have 3 things you're responsible for tonight and for our (likely) snow day:

1.) Study your chapter 13 vocab! You will have a chapter 13 vocab quiz in class the next time you see me (probably Friday)!

• You defined each of the vocab terms in answering your chapter 13 reading questions over break!
• There are 15 vocab words for this quiz!
• Here's your vocab list: (some definitions provided in parentheses)
• Experiment (method of data collection where we randomly assign treatments, only method that allows us to establish cause and effect)
• Observational Study (no manipulation of factors, no assignment of treatments)
• Retrospective Observational Study: observational study where existing data on the subjects' past behaviors/history is examine
• Prospective Observational Study: observational study where subjects are identified, then data is collected over time/moving forward
• Factor(s)
• Level(s) (the values chosen for a factor)
• Treatment(s)
• Response Variable
• 4 Principles of Experimental Design: (Control, Randomize, Replicate, Block)
• Random Assignment (in an experiment treatments are randomly assigned to participants)
• Control Group
• Blocking
• Blinding (when certain people--those receiving the treatments and/or those evaluating the results/collecting the data--are unaware what treatment group a subject was/is in)
• Single Blind v. Double Blind
• Placebo (used with our control group to help with blinding our experiment)
• Confounding 
• Matching (when subjects in an observational study are specifically paired and compared)
• Replication
• Control Group (a group that receives a baseline treatment or no treatment, often using a placebo)
• Statistically Significant (when the differences/changes in the response variable are too noticeable to be caused by natural variation and are thus attributed to the changes in our factor)

2.) STAMPS are due at our next class!

• Count your stamps!
• Write the total on the front! Double check!
• Your total must be correct! If I randomly select your name and double check your total and it's incorrect you will be given a 0 for your stamp grade.
• Get these all together--put them in a bag, an envelope, staple them--somehow get these all together
• If it's easier to rip a stamp off the corner of a paper than give the whole paper--do that! 

3.) STUDY, STUDY, STUDY for you Midterm! 

• Today I provided you with an outline of the topics on our exam as well as a variety of additional practice problems you can use to study!
• Answers to the stuff you got today in class will be posted on the blog (by Saturday)
• You also have the documents I sent you via email--the 2015 midterm (practice exam)!
• You can also use practice problems on sites like Khan Academy or using the sites linked on the right!
• Check out this image for more ideas about how to study!
• 
  
  

Tuesday HW = Midterm Review!

1.) Tonight please COMPLETE AND SCORE the "pinata" free response question provided in class (or below)---this is some review for next week's midterm!

• We have questions on our midterm that challenge us to work with expected value--reviewed with this question!
• We also have a probability free response on our midterm that is similar to this context in the sense that you have work to calculate "and" probabilities, but the probability of successfully breaking the pinata changes with each hit
• In other words....this is a good problem to use for review! :)

Here is the homework free response question:

And here is the answer key and scoring rubric you can use to grade your free response:

2.) STAMPS are due Thursday (or Friday)! Start counting now!

• Count your stamps!
• Write the total on the front! Double check!
• Your total must be correct! If I randomly select your name and double check your total and it's incorrect you will be given a 0 for your stamp grade.
• Get these all together--put them in a bag, an envelope, staple them--somehow get these all together
• If it's easier to rip a stamp off the corner of a paper than give the whole paper--do that! 

3.) Check out the image below for some suggestions about how to study:

4.) If you are interested in taking an MCC class for credit please let me know ASAP!

• The course is MCC's "Math 138," or like our Math Modeling course
• This is a college algebra class--a lot of the stuff you learned in Algebra 2 and PreCalc 
• The course is taught by Ms. Beauchamp
• The class starts January 18th and ends May 10th
• Class is from 3:00-5:50 every Thursday
• You must provide your own transportation
• The class meets once a week so you must be highly responsible and do a substantial amount of work independently
• Grades will only be based on your quizzes and tests in class--your grade is only based on your ability/performance, not effort (it's a college class!)
• There are only 15 spots available
• Highly motivated students will be given first priority
• There is a permission slip! See me the day we're back!
• Or, email Joanna White (jwhite1@manchestercc.edu) if you have questions