The Histogram by alicejenny

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									Stat 216- handout 1
Spring 2003
How To Get The Stem and Leaf Plot Using Excel/PHstat?

A data set of the midterm scores are:
 68    94   63   75   71   88   64

Use the above data to get the stem and leaf plot.
The steps:
   1) Pull down the PHstat menu and choose descriptive statistics. Then choose stem and
       leaf plot.
   2) Enter the data as following :




      3) The output :
                                     Stem-and-Leaf Display
                                     for scores
                                     Stem unit:          10

        Statistics                                   6   348
 Sample Size            7                            7   15
 Mean            74.71429                            8   8
 Median                71                            9   4
 Std.
 Deviation       11.96821
 Minimum               63
 Maximum               94
Stat 216- handout 1
Spring 2003
How To Plot A Histogram Using Excel/PHstat?
Use data set UTILITY.XLS

 96   171    202    178   147   102   153   197   127           82       157        185      90        116         172     111        148         213      130
165   141    149    206   175   123   128   144   168          109       167         95     163        150         154     130        143         187      166
139   149    108    119   183   151   114   135   191          137       129        158
To get an idea about the classification of the data, follow the first two steps.
1- Draw the stem and leaf plot first to find    2- Create a new column named Bin including
the categories (intervals or Bins).             the categories.
             8     2                                                 bin
             9     056                                                80
            10     289                                                90
            11     1469                                              100
            12     3789                                              110
            13     00579                                             120
            14     1347899                                           130
            15     013478                                            140
            16     35678                                             150
            17     1258                                              160
            18     357
            19     17
            20     26
            21     3

3-Under PHstat menu, choose descriptive statistics and then Histogram. Enter all
information as you see below,
                                       The output:

                                                                                                 Histogram

                                                                    10
                                                                     8
                                                        Frequency




                                                                     6
                                                                     4
                                                                     2
                                                                     0
                                                                                                                                                         210+
                                                                         80
                                                                               90
                                                                                     100
                                                                                           110
                                                                                                 120
                                                                                                       130
                                                                                                             140
                                                                                                                    150
                                                                                                                          160
                                                                                                                                170
                                                                                                                                      180
                                                                                                                                            190
                                                                                                                                                   200




                                                                                                   Categories (bins)
Stat 216- handout 1
Spring 2003
How To Plot A Histogram Using TI-83?

Entering data
The easiest way to enter a list of data is to use STAT Edit. Suppose we wish to enter the
following list:
                                 25, 18, 12, 27, 34, 48
Let’s enter it into the default list L1.




Leave the editor by pressing <2nd>QUIT.

Press <2nd>STAT PLOT. Note that there are three plots you can specify for display (all at
once if you wish!)

Choose Plot1. Change it from Off to On.
There are six types of plots to choose from. Move the cursor over to the third one in the first
row. This is a histogram. Press ENTER.

The argument for Xlist should be L1, the list containing our data. If we had any frequency
counts in another data list, this would need to be entered for Freq. This is not the case for our
example, so leave it as "1", the default.

Once this is done, press GRAPH. You may need to make some adjustments before the plot
will show up on the screen. A good way to get a quick viewing window appropriate for the
data and for the plot type selected is ZoomStat: Press ZOOM, then choose 9: ZoomStat.

If this does not result in an adequate graph, press WINDOW to see some of the
specifications. For a histogram, Xscl is the width of the intervals.
Stat 216- handout 1
Spring 2003




While viewing the histogram, pressing TRACE will allow you to get more information out of
the graph. For example, the image above shows that the second rectangle, which represents
the interval [21, 30), contains two observations.

Move the cursor left and right to get information on each interval.

								
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