March 12, 2103
OGT TESTING
Today's Agenda:
1. Transfer Group called ICECREAM to graphing calculators
2. Activity 10­3: Ice Cream Calories
3. HW: Finish Activities 10­6, 10­9 & 10­19
Activity 10­3: Ice Cream Calories
(NEED LISTS: BJCAL, CSCAL, DYCAL)
(a)
Use 1­Var Stats to compute the 5­number summary for calories in each brand of ice cream.
(b)
110
220
265
290
360
130
360
390
400
440
90
110
120
150
190
Use your calculator to construct modified boxplots of the distribution of calorie amounts.
Plot 1 = Ben & Jerry's
Plot 2 = Cold Stone Creamery
Plot 3 = Dreyer's
(3)
(2)
(1)
How do the three brands' calories compare based on these boxplots?
When making comparisons, look at where the quartiles can be compared.
The dotted lines above show that: (1) 75% of Cold Stone's ice creams have more calories than all of Ben & Jerry's and all of Dreyer's; (2) 75% of Ben & Jerry's ice creams have more calories than all of Dreyer's; and (3) 25% of Dreyer's ice creams have fewer calories than all of Ben & Jerry's and Cold Stone's ice creams.
(c)
Can you speculate about a possible problem with making comparisons of calorie amounts? (Hint: There is one piece of descriptive information not given.)
In order to make any comparisons between any different items, we need to make sure they are being measured on the same scale with the same units. We don't know if that's the case here.
Ben & Jerry's and Dreyer's both consider a serving size as 1/2 cup.
Cold Stone Creamery considers a serving size as 170 grams.
(The comparative boxplots were not comparing equivalent measurements.)
(d)
How would you propose (in general terms) to adjust for this discrepency in serving size?
We need to convert Cold Stone's serving size into a 1/2 cup serving size.
(e)
Using the conversion 1 cup = 146 grams (or 1/2 cup = 73 grams),
how could you convert Cold Stone Creamery's calorie information from grams to cups (making Cold Stone's calorie information comparable to the others)?
Calculate how many calories are in 1 gram of ice cream (divide each of Cold Stone's servings by 170), then multiply it by 73 grams to make a 1/2 cup serving size.
(f)
Use your calculator to do the conversion and create a new list for Cold Stone:
(1) Find the number of calories per gram:
LCSCAL/170
(2) Find the number of grams in 1/2 cup:
Ans * 73
(3) Save the new list :
STO>
CSHCC
(Cold Stone Half Cup Calories)
(g)
(h)
Now, let's compare 5­number summaries again using similar units:
110
220
265
290
360
56
155
168
172
189
90
110
120
150
190
Let's also reconstruct the boxplots.
Plot 1: Ben & Jerry's
Plot 2: Cold Stone Creamery
Plot 3: Dryer's
(3) (2)
(1)
Comment on what the boxplots reveal now about how the three ice cream brands' calories compare.
Now we can see that Ben & Jerry's ice creams have more calories than the other ice creams. In fact, (1) 75% of Ben & Jerry's have more calories than all of the others; (2) 75% of Cold Stone's have more calories than 75% of Dreyer's; and (3) 25% of Dreyer's have fewer calories than all of Ben & Jerry's. In addition, Cold Stone has the most outliers so perhaps they have several frozen yougart options.
FINISH Homework #1:
Use the worksheet provided for your answers.
The questions are in the book.
Activity 10­6 Activity 10­9 (use the list of data provided in class from the last Topic) Activity 10­19