Standard deviation

• What is the formula to calculate the standard deviation, σ?

  σ = √(Σx²/n) - (Σx/n)²
• What is the formula to calculate Σ(x - x̄)²?


  Σ(x - x̄)² = Σ of (x - mean)²
• How do you find the standard deviation of the weights given Σ(x - x̄)²?

  Standard deviation = √(Σ(x - x̄)² / n)
• What are the steps to calculate the standard deviation from a set of data values?

  1. Calculate the mean (x̄).
  2. Find Σ(x - x̄)².
  3. Use the formula: σ = √(Σ(x - x̄)² / n).
• What are the key components needed to calculate the standard deviation for a given data set?


  • Σx (sum of data values)
  • Σx² (sum of squared data values)
  • n (number of data values)
  • Mean (x̄)