Determine the appropriate measure to be displayed For a column bar chart, locate the categories on the horizontal axis. For a horizontal bar chart, place the categories on the vertical axis. Then construct bars, either
vertical or horizontal, for each category such that the length or height corresponds to the value for the category. Interpret the results. Pie Charts: a graph in the shape of a circle. The circle is divided into “slices” corresponding to the categories or classes to be displayed. The size of each slice is proportional to the magnitude of the displayed variable associated with each category or class. Steps: Define the categories for the variable of interest. Determine the appropriate measure or value. The value is assigned to each category is the proportion the category is to the total for all categories. Construct the pie chart by displaying one slice for each category that is proportional in size to the proportion the category value is to the total of all categories. Quantitative Data: Stem and Leaf Diagrams Steps: Sort the data from low to high. Analyze the data for the variable of interest to determine how you wish to split the values into a stem and a leaf. List all possible stems in a single column between the lowest and highest values in the data. For each stem, list all leaves associated with the stem. 2.3 Line Charts and Scatter Diagrams Line Chart: a twodimensional chart showing time on the horizontal axis and the variable of interest on the vertical axis. Ex. how the price of stock has changed over the last 3 months Steps: Identify the timeseries variable of interest and determine the maximum value and the range of time periods covered in the data. Construct the horizontal axis for the time periods. Construct the vertical axis with a scale appropriate for the range of values. Plot the points of the graph and connect them with straight lines. Scatter Diagram (Plot): A twodimensional graph of plotted points in which the vertical axis represents values of one quantitative variable and the horizontal axis represents values of the other quantitative variable. Each plotted point has coordinates whose values are obtained from the respective variables. Dependent Variable: a variable whose values are thought to be a function of, or dependent on, the values of another variable called the independent variable . On a scatter plot, the dependent variable is placed on the y axis and is often called the response variable.
Independent Variable: a variable whose values are thought to impact the values of the dependent variables . The independent variable, or explanatory variable, is often within the direct control of the decision maker. On a scatter plot, the independent variable, or explanatory variable, is graphed on the x axis.
You've reached the end of your free preview.
Want to read all 18 pages?
- Fall '11