Stemplots &Histograms

Stemplot – (Stem & Leaf) – Let’s find our pulse rates.

What’s your height? Compare.

Male Female

Sometimes we have to truncate the data.

145 378 630 317

287 572 547 228

122 564 231 279

138 238 444 209

Grade point avg.

3.4 4 3.9

2.1 2.2 3.8

2.7 2.8 2.9

1.9 3.2 2.1

Make & describe a stemplot

229 247 347

246 198 260

320 360 414

214 218 276

197 406 261

347 223 196

202 628

Histogram: Class width

Range = Largest – Smallest

Rangewidth =

#classes

28 32 44 21

45 38 40 22

mpg of cars: 27 21 23 25 25

25 23 22 24 27

29 28 22 38 18

26 33 27 52 43

Actually…I can use any scale that I choose!

mpg of cars: 27 21 23 25 25

25 23 22 24 27

29 28 22 38 18

26 33 27 52 43

Salaries of CEO’s (nearest thousand):

250 621 262

750 368 659

862 204 206

149 350 242

145 396 572

# credit card returns: (on the calculator…)36 57 75 73

32 49 63 35

35 35 47 39

28 42 41 24

Using the calculator

Put data in L1 Go to 2nd y= Turn on, turn on histogram (make sure xlist is

L1 or whatever list your data is in) Hit zoom9 Go to window. Set xmin to smallest value

and scl = class width. Press graph. (Trace will show all values)

Categorical Graphs

Quantitative Graphs

Homework

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