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Warm UpResearchers deigned an observational study to investigate
the accepted normal body temperature of 98.6F. In the study, 148
healthy men and women ages 18 to 40 had their temperatures taken
several times over a three-day period. A total of 700 temperature
readings were produced. Explain why this is an observation study
and not an experiment.To what population does the conclusion about
normal body temperature apply? Justify your answer.Look at the
first dot plot (the vertical line at 98.6F is for reference). What
does this graph tell you about normal?
Look at the second set of dot plots. How do male and female
temperature compare? Write a few sentences comparing normal body
temperatures for males and female in the study.List and describe as
many possible sources of variation in this study as you can.
When data is presented without a table or in no specific order
like this, what is the data called?23 48349352 79537626
7235784Lesson 4: Stem PlotsRaw DataDefinitionSometimes the values
of a variable are too spread out for us to make a reasonable dot
plot by hand. In these cases, we can consider another simple
graphical display called a stem plotsometimes referred to as stem
and leaf plots.Example:11 222 2 331 4 42 3 4 4 552 61 1
370Constructing a Stem & Leaf PlotThere are 4 Steps to
constructing a stem & leaf plot. They are summarized on pg. 45
of your textbook.At an outpatient testing center, the number of
cardiograms performed each day for 20 days is shown.25 31 20 32
1314 43 02 57 2336 32 33 32 4432 52 44 51 45Raw DataStep 1:Arrange
the data in numerical order and separate/group according to the
first digitConstructing a Stem & Leaf Plot25 31 20 32 1314 43
02 57 2336 32 33 32 4432 52 44 51 45Original Raw DataStep
2:Separate data into A stem, the leading digits, consisting of all
but the right-most digitA leaf, the final digit
Stems may have as many digits as needed, but each leaf contains
only a single digit.Constructing a Stem & Leaf PlotStep
3:Separate data putting the leading digit in the left column with
the smallest at the top and all of the final digits in their
corresponding rows in increasing orderLeading digit (stem)Final
Digit (leaf)01234523 40 3 51 2 2 2 2 3 63 4 4 51 2 7Constructing a
Stem & Leaf PlotStep 4:Divide the leading digit and trailing
digit by a vertical line 01234523 40 3 51 2 2 2 2 3 63 4 4 51 2
7_______________________Constructing a Stem & Leaf PlotA
particular class of 18 students took a test and the grades were:75
82 92 88 6481 61 84 77 9766 73 88 89 7988 77 69
Try one on your own:A particular class of 18 students took a
test and the grades were:67891 4 6 93 5 7 7 91 2 4 8 8 8 92
7_________________________AnswerKey ConceptTo see the overall
pattern of a distribution, ignore any outliers. Describe the
overall pattern of the distribution by giving the center and the
spread, and see if the distribution has a simple shape that you can
describe in a few words.
Shape:
Center:
Spread:Key ConceptKey ConceptWhether youre given raw data or the
stem & leaf plot you will have to find.
Mean:
Median:
Mode:
Range:ExamplesMean:
Median:
Mode:
Range:Raw Data15223140173242182531324141411520ExamplesMean:
Median:
Mode:
Range:Stem Plot 1 5 5 7 2 0 2 5 3 1 1 2 2 4 0 1 1 1Questions on
pg. 46-59#s 2.8, 2.11, 2.12, 2.19, 2.26
Mean, Median, Mode, & Range WorksheetHomework:
