Using the data below, what is the value of MSE?

Week1, Actuasl=7, Forecast=4.00
Week2, Actuasl=15, Forecast=4.00
Week3, Actuasl=14, Forecast=16.00
Week4, Actuasl=13, Forecast=17.00

1 answer

To calculate the Mean Squared Error (MSE), we first need to find the squared errors for each week. The squared error is calculated as follows:

\[ \text{Squared Error} = (\text{Actual} - \text{Forecast})^2 \]

Let's calculate the squared errors for each week:

  1. Week 1:

    • Actual = 7
    • Forecast = 4.00
    • Squared Error = \((7 - 4)^2 = (3)^2 = 9\)
  2. Week 2:

    • Actual = 15
    • Forecast = 4.00
    • Squared Error = \((15 - 4)^2 = (11)^2 = 121\)
  3. Week 3:

    • Actual = 14
    • Forecast = 16.00
    • Squared Error = \((14 - 16)^2 = (-2)^2 = 4\)
  4. Week 4:

    • Actual = 13
    • Forecast = 17.00
    • Squared Error = \((13 - 17)^2 = (-4)^2 = 16\)

Now, we can sum up the squared errors:

\[ \text{Total Squared Error} = 9 + 121 + 4 + 16 = 150 \]

Now, we calculate the Mean Squared Error (MSE) by dividing the total squared error by the number of observations:

\[ \text{MSE} = \frac{\text{Total Squared Error}}{n} = \frac{150}{4} = 37.5 \]

Thus, the value of MSE is 37.5.