線性回歸

線性回歸（Linear Regression），參照：『維基百科～Linear_regression』

應用

C#

• What is the C# equivalent to LINEST from Excel?

public static double CalculateLinest(double[] y, double[] x)
{
   double linest = 0;
   if (y.Length == x.Length)
   {
      double avgY = y.Average();
      double avgX = x.Average();
      double[] dividend = new double[y.Length];
      double[] divisor = new double[y.Length];
      for (int i = 0; i < y.Length; i++)
      {
         dividend[i] = (x[i] - avgX) * (y[i] - avgY);
         divisor[i] = Math.Pow((x[i] - avgX), 2);
      }
      linest = dividend.Sum() / divisor.Sum();
   }
   return linest;
}

Excel

• LINEST 函數 - Office 支援
• LINEST function - Office Support