Assignment 3 HED 489 Biostatistics

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Assignment 3HED 489 Biostatistics
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Assignment 3

• Read
• Kuzma
• Chapter 3
• Dummies
• Chapter 4
• Do the chapter exercises

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Additional Assignments

• Go through this tutorial to prepare you for
  assignments later on in this slide presentation.

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The nice thing about a spreadsheet isthe ability
to sort data. Instead of retypingeverything,
you can instruct the systemto sort.
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First, Ive copied the data from A2 to A26 25
scores into column D. Ive renamed the column
Sort.
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Take the cursor and highlight thecells that you
would like to sort. Note thatcells D2D26 are
highlighted.Then go up to the Data menu and
Pull downhighlight the sort response
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What you will get now is this Sort Box Note
that it highlights the data youve
selectedSort and it is asking whether you want
the datato go low to high (Ascending) or High to
low (Descending). In this case, wellkeep
ascending highlighted. Click OK
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After you click OK youll seethe data that
ranges from 10 to 21. Thus, the range ofscores
are between these scores. Note that there are two
scores of 10,two of 11, three 13s, one 14,
four15s, four 16s, two 17s, one 18,two 19s, one
20, and one 21
Assignment
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What well do now is to go to the next column,
name it N for number, andput into the cell the
number of each score. Youll note thatthere are
spaces between corresponding to the number
ofscores
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Note that Ive now copiedthe data from column G
H into columns J and K Its more compact(and
itll make it easier to create a table if so
desired)
Assignment
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To ensure that you havent missed anything, you
can sum the score of column Knote that by
highlighting cell K14, and then clicking the Sum
icon, youll getthis configuration shown above.
It automatically identifies the cells you want
summed.
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After hitting the enter button, youll see the
total sum. In this case, it is 25the number of
scores as in Columns A, D, G.
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Now sometimes its important to know
whatpercentage each score represents of the
total group.For example, two individuals scored
10what percentage is this of the total group
(N25).You can do it by hand, but Excel
(andalmost all spreadsheets) will do this
automatically.First, highlight cell L2. Then in
thecode bar, type an equal signnow, move
your cursor into the mathematicalcodeK2,
divided by / K25 25times 100then hit the
enter key
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Youll note that the percentageof individuals
who scored 10 was 8. What you dont know is if
it is exactly8, or if its been rounded.To
configure the decimal point,highlight cells
L2L13then right click the mouse toget this
menuthenhighlight Format Cells
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Youll now have this folderappear. You can
select a variety ofcategories, including the
type of numbering andthe number of decimal
points. In this case well select 2. Hit OK
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So now we know that there was exactly 8 ofthe
total number scored 10. Do the rest of the
scores in the same fashion.
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As you can imagine, the 2 individuals who
scored11 represent 8 of the sample.
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As we go through all of the scores, you can
seethe percentages range from 4 up to 16.
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As we did with the raw numbers, to ensure that
you included everybody, youll want to sum up
the numbers in L2L14. Go to cell L15, clickthe
sum icon, then hit enter.
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So the total of your percentages come to 100.00.
It is possible that with somecolumns it will
not total 100.00. That doesnt necessarily mean
that theresults are wrong, it is possible that
the researcher rounded up (or down) numbersand
those numbers dont equal 100.00. Thats ok,
BUT, the researcher shouldnote somewhere that
the total doesnt equal 100 due to rounding
error.
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OK, Ive taken that previous dataand copied it
into a new sheet in Excel. Ive relabeled some
of thedata. The title of this data isthe
number of individuals kissedwithin the past 2
days. Excel allows you to make veryattractive
tables that you can copy andpaste into other
documents such as Word or Power Point.
Assignment
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Now Im going to add two morecolumns. Columns D
E are added to include CumulativeNumber and
Cumulative Percentageplease note that the
word cumulative is misspelledin the
spreadsheet Having these numbers allows
theindividual to see not only the percentage of
each scoreindividually, but gives one a
running score. If donecorrectly, Cumulative
Numbershould total the N, and Cumulative
Percent shouldequal to total Percent
Assignment
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Another important task is to have
cross-tabulations.This will be an example of a
simple cross-tab. Note in Columns B we have
peoples Gender, with m representing males and
f representing females. In column C we have a
list of their IQs.
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Theres a number of ways to do this, butfor this
example, lets do it simple.Either the people in
this list are smart or dumb.Well recode the IQ
with either of theseterms. We need to determine
what numberis the cut-off to determine smart or
dumb. For giggles and grins, lets say 100 is
thecutoff. Thus, those who scored 100 orhigher
are recoded as smartthose under100 are dumb.
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Cross-tabs are often represented in the above
table. In this case, it is a 2 x 2 table. The
verrtical side is the IQ status (smart or
dumb)the horizontal data represents whether one
is a male or female. Now, to complete this
table, just add the number of Smart Males,
DumbMales, Smart Females, and Dumb Females.
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So of our 10 items (4 males and 6 females), its
evenly split amongthe femaleswhere the males
there are three times more smart males than dumb
males. You can also state that there are even
number of smart males and femalesand that there
are three times more dumb females than males.
Assignment
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• Click here to open Frequency Assignment 1. Here
  is a list of 50 individuals and the number of
  reported kisses theyve had within the past,
  along with their gender, age. With this data, do
  the following (links will help refresh your
  memory)
• Sort from least to most kisses
• Collapse the data
• Percent
• Cumulative Number and Percent
• Cross-Tabulation
• Use gender and kisses
• When through, send it to me at kitt_at_siu.edu