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6-8, 9-12
Standards:
Math Content:
Data Analysis and Probability

The Advanced Data Grapher can be used to analyze data with box plots, bubble graphs, scatterplots, histograms, and stem-and-leaf plots. You can enter multiple rows and columns of data, select which set(s) to display in a graph, and choose the type of representation. (To analyze data with bar graphs, line graphs, pie charts, or pictographs, try the Data Grapher.)

### Types of Graphs

Five different types of graphs may be selected using the selector buttons at the top of the main screen:

The five types of graphs that may be selected:

1. Box – Data from one or multiple columns will be displayed in a box plot.
• On the main screen, select which columns to display and the color for each column.
• On the preview screen, you will have the option of displaying "All Data" or "By Category." If multiple columns were selected on the main screen, then displaying the data by category will yield multiple box plots, whereas displaying all data will yield a single box plot that aggregates data from every selected column. You will also be able to "Exclude Outliers" and set the "Tolerance." The tolerance is the coefficient of the inter‑quartile range that will be used to determine which points are outliers.

2. Bubble – Data from three columns will be displayed in a bubble graph (where a circle is placed with center (xy), and the radius of the circle is indicated by "size.")
• On the main screen, select three columns — two to be used for the x and y values, and a third to be used for "size."
• On the preview screen, you will have the option of displaying a legend.

3. Scatterplot – Data from two columns will be displayed in a scatterplot.
• On the main screen, select two columns to be used for the x and y values.

4. Histogram – Data from one column will be displayed in a histogram.
• On the main screen, select which column to display. (Because row names are irrelevant for this type of representation, you will not be able to modify the row names when the Histogram button is selected.)
• On the preview screen, you will have the option of displaying the graph with or without a frequency table, and you will be able to choose the color of the bars. You will also be able to indicate the bin size for the histogram; however, the bin size must allow for a minimum of three bins.

5. Stem-Leaf – Data from one or two columns will be displayed in a stem‑and‑leaf plot.

### How to Use

• On the main screen, select which columns to display.
• On the preview screen, a stem-and-leaf plot (one column) or a back-to-back stem-and-leaf plot (two columns) will be displayed. You will have the option of displaying the stem with one or two digits.
•  Data can be entered in multiple rows and columns. To add rows and columns, use the Add Row and Add Column buttons:
• Although there is no limit to the number of rows that may be added, no more than six columns of data are allowed.
• Click in a cell to add or change data, or to update the row or column name. You can also move between cells using the TAB key on the keyboard. Numbers can contain decimal points, but cannot contain commas or other symbols. Data entered in multiple rows and columns will appear as follows:
• A Graph Title, X Axis Title and Y Axis Title can be entered to provide further information. (Note that Y Axis Titles are not permitted for Box Plots or Stem-and-Leaf Plots.) Values can be entered for Min. Value and Max. Value to set the minimum and maximum values displayed on the y‑axis. The values displayed on the x‑axis are automatically determined by the data values that have been entered in the rows and columns.
• After data has been entered, the Preview button (see right) may be used to view the graph.
• From the preview screen, click Print to print a copy of the graph.