session one:Graphing data

The story

You work for a company that produces pressure treated lumber products. Chromated copper arsenate, or CCA, is commonly used by your industry to make wood less susceptible to rot and insect damage. However, CCA has come under attack by groups worried about potential health risks associated with lumber treated in this manner. You are investigating the viability of a new, entirely organic compound that may be able to replace CCA, maintaining the quality standards of your products and satisfying public interest groups. You have conducted a study and saved the results in the worksheet PRESSURE.MTW:

In your study, you attempted to simulate how well CCA and the new organic compound protect wood over a 60 year period. Uniform planks of pine were treated with both products at three standard saturation levels and then placed in an aging chamber. The planks were then tested for their load bearing properties to see how well the different treatment regiments preserved the wood.

The variable Solution recorded whether the product used was CCA (Solution = 1) or organic (Solution = 2).

Retention states the amount of solution applied to each plank: 0.25 pounds of preservative per cubic foot of wood, the standard for above ground applications, 0.8 lbs/cubic foot, the standard for foundation piles, and 2.5 lbs/cubic foot, the standard for salt water applications.

The values listed in Hours are the number of hours each plank spent in the aging chamber. One hour is considered equivalent to one year of exposure to the elements.

Load lists the maximum load weight in pounds for each plank following the preservative treatment and aging process.

You have been asked to present these findings to your group manager and have set the following objectives for yourself:

· Create two graphs that best represent the data.

· Edit the graphs for clarity.

· Combine the graphs in a layout.

· Prepare a short report discussing what the graphs say about the data, and include the graphs in this document.
What you will learn

In this session, you will learn how to:

· Choose an appropriate graph.

· Apply common graph options when creating a graph.

· Explore graphed data without altering the graph.

· Select and edit the attributes of different graph items.

· Alter the variable used to create a graph.

· Add items to a graph.

· Use a grouping variable to alter the display of a graph.

· Create a layout of several graphs.

· Edit a Minitab graph in other software applications.

· Use command language to create graphs.