C# Two Way Ranova Example

← All NMath Code Examples

 

using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
using System.IO;

namespace CenterSpace.NMath.Examples.CSharp
{
  /// <summary>
  /// A .NET example in C# showing how to use class TwoWayRanova to perform a two-way ANOVA
  /// with repeated measures on one factor.
  /// </summary>
  /// <remarks>
  /// This example was constructed with a Visual Studio wizard. The code
  /// generated by the wizard is contained in the region labelled "Windows Form
  /// Designer generated code". The example code is contained in the
  /// constructor for the class TwoWayRanovaExample.
  /// </remarks>
  public class TwoWayRanovaExample : System.Windows.Forms.Form
  {
    private System.Windows.Forms.DataGrid dataGrid1;
    private System.Windows.Forms.Label label1;

    /// <summary>
    /// Required designer variable.
    /// </summary>
    private System.ComponentModel.Container components = null;

    /// <summary>
    /// Constructor for class TwoWayRanovaExmaple.
    /// </summary>
    public TwoWayRanovaExample()
    {
      //
      // Required for Windows Form Designer support
      //
      InitializeComponent();

      // Read in data from a file. The file contains data for a test for
      // contamination of surgical scrub suits. One group of workers changed
      // their scrub suit at lunch, while the other group wore a surgical 
      // gown to lunch and did not change their scrub suits. Bacterial
      // contamination level of the scrub suits was measured at 3 times
      // during the workers shifts. The nonrepeated factor is the scrub suit
      // group (change or not change), the repeated factor is time.
      DataFrame anovaData = DataFrame.Load( "TwoWayRanovaExample.dat", true, false, " ", true );

      // Class TwoWayRanova performs a balanced two-way analysis of variance with
      // repeated measures on one factor. Multiple linear regression is used to 
      // compute the RANOVA values. The constructor takes a DataFrame
      // containing the data, and the column indices of the repeated factor, 
      // the nonrepeated factor, and the contamination level.
      var anova = new TwoWayRanova( anovaData, 1, 2, 0 );

      // This example simply displays a traditional RANOVA table
      // in a System.Windows.Forms.DataGrid object. The next few lines of
      // code format the table contents.

      // First retrieve the table to display. Class TwoWayRanovaTable is a
      // subclass of DataFrame.
      TwoWayRanovaTable anovaTable = anova.RanovaTable;

      // Next, lets set the precision to three decimal places. Note that this
      // does not actually change the numbers in the RANOVA table. It just
      // determines how many decimal places are displayed when the table is
      // converted to a string.
      ( (DFNumericColumn) anovaTable[1] ).NumericFormat = "F0";
      for ( int i = 2; i < anovaTable.Cols; ++i )
      {
        ( (DFNumericColumn) anovaTable[i] ).NumericFormat = "F3";
      }

      // Next convert the RANOVA table into a string. This has the effect of 
      // formatting all the numbers so that they have three digits after the decimal
      // point and all Double.NaN values are represented as a ".". (Some rows
      // in the ANOVA table that do not have F statistic values or F statistic
      // p-values associated with them. The cells that correspond to these rows
      // and the F and P columns contain Double.NaN values.)
      var displayFrame = new DataFrame( anovaTable.ToString(), true, true, "\t", false );

      // Note that in the previous line we passed a value of false for the 
      // parse parameter to the DataFrame constructor (the last parameter). 
      // This gives us a DataFrame object in which all the column types
      // are strings. This lets us format the data easily.

      // If the p-value for the F statistic is too small, it is rounded
      // to zero when we set the precision to three decimal places. It doesnt
      // look good to have a p-value of 0 in our display, so lets display
      // something a bit more sensible like display "< 0.001".
      int rowIndex, colIndex;
      if ( anovaTable.FstatisticPvalue( "ScrubSuit" ) < .001 )
      {
        colIndex = displayFrame.IndexOfColumn( TwoWayAnovaTable.PvalueColName );
        rowIndex = displayFrame.IndexOfKey( "ScrubSuit" );
        displayFrame[rowIndex, colIndex] = "< 0.001";
      }

      if ( anovaTable.FstatisticPvalue( "Time" ) < .001 )
      {
        colIndex = displayFrame.IndexOfColumn( TwoWayAnovaTable.PvalueColName );
        rowIndex = displayFrame.IndexOfKey( "Time" );
        displayFrame[rowIndex, colIndex] = "< 0.001";
      }

      if ( anovaTable.InteractionFstatisticPvalue < 0.001 )
      {
        colIndex = displayFrame.IndexOfColumn( TwoWayAnovaTable.PvalueColName );
        rowIndex = displayFrame.IndexOfKey( TwoWayAnovaTable.InteractionRowKey );
        displayFrame[rowIndex, colIndex] = "< 0.001";
      }

      // Finally, display the ANOVA table in the DataGrid.
      this.dataGrid1.DataSource = displayFrame.ToDataTable();

      // The interaction effect indicates that the change in bacterial counts
      // over time is different in the two groups (F = 24.163, p < 0.001). The
      // main effect of time is also highly significant (F = 25.9, p 0.001). 
      // The difference between scrub suit groups is insignificant (F = 3.86,
      // p = 0.057).
    }

    /// <summary>
    /// Clean up any resources being used.
    /// </summary>
    protected override void Dispose( bool disposing )
    {
      if ( disposing )
      {
        if ( components != null )
        {
          components.Dispose();
        }
      }
      base.Dispose( disposing );
    }

    #region Windows Form Designer generated code
    /// <summary>
    /// Required method for Designer support - do not modify
    /// the contents of this method with the code editor.
    /// </summary>
    private void InitializeComponent()
    {
      this.dataGrid1 = new System.Windows.Forms.DataGrid();
      this.label1 = new System.Windows.Forms.Label();
      ( (System.ComponentModel.ISupportInitialize) ( this.dataGrid1 ) ).BeginInit();
      this.SuspendLayout();
      // 
      // dataGrid1
      // 
      this.dataGrid1.BackgroundColor = System.Drawing.Color.White;
      this.dataGrid1.CaptionVisible = false;
      this.dataGrid1.DataMember = "";
      this.dataGrid1.HeaderForeColor = System.Drawing.SystemColors.ControlText;
      this.dataGrid1.Location = new System.Drawing.Point( 24, 112 );
      this.dataGrid1.Name = "dataGrid1";
      this.dataGrid1.PreferredColumnWidth = 110;
      this.dataGrid1.ReadOnly = true;
      this.dataGrid1.RowHeadersVisible = false;
      this.dataGrid1.Size = new System.Drawing.Size( 664, 128 );
      this.dataGrid1.TabIndex = 0;
      // 
      // label1
      // 
      this.label1.Font = new System.Drawing.Font( "Microsoft Sans Serif", 14.25F, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, ( (System.Byte) ( 0 ) ) );
      this.label1.Location = new System.Drawing.Point( 145, 24 );
      this.label1.Name = "label1";
      this.label1.Size = new System.Drawing.Size( 424, 64 );
      this.label1.TabIndex = 1;
      this.label1.Text = "Two Way Anova With Repeated Measures\r\nOn One Factor Example";
      this.label1.TextAlign = System.Drawing.ContentAlignment.MiddleCenter;
      // 
      // TwoWayRanovaExample
      // 
      this.AutoScaleBaseSize = new System.Drawing.Size( 5, 13 );
      this.ClientSize = new System.Drawing.Size( 714, 272 );
      this.Controls.AddRange( new System.Windows.Forms.Control[] {
                                                                  this.label1,
                                                                  this.dataGrid1} );
      this.FormBorderStyle = System.Windows.Forms.FormBorderStyle.FixedSingle;
      this.Name = "TwoWayRanovaExample";
      this.Text = "TwoWayRanovaExample";
      ( (System.ComponentModel.ISupportInitialize) ( this.dataGrid1 ) ).EndInit();
      this.ResumeLayout( false );

    }
    #endregion

    static void Main()
    {
      Application.Run( new TwoWayRanovaExample() );
    }

  }  // class

} // namespace



← All NMath Code Examples
Top