Consider the following partially completed ANOVA, and answer the following: give the value of (C). / Beskou die onvoltooide ANOVA en beantwoord die volgende: gee die waarde van (C).




ANOVA

Source SS df MS Fstat Ftab
Treatment 12 689 (C) (F) 10.6642 (G)
Error (A) (E) 595.3611
Total (B) 11

1 answer

To complete the ANOVA table, we need to understand the relationships between the columns.

  1. Degrees of Freedom (df):

    • For treatments (C), df = k - 1, where k is the number of groups.
    • For error (E), df = N - k, where N is the total number of observations.
    • For total (B), df = N - 1.
  2. Mean Square (MS):

    • For treatments, \( MS_{\text{Treatment}} = \frac{SS_{\text{Treatment}}}{df_{\text{Treatment}}} \),
    • For error, \( MS_{\text{Error}} = \frac{SS_{\text{Error}}}{df_{\text{Error}}} \).
  3. F-statistic:

    • \( F = \frac{MS_{\text{Treatment}}}{MS_{\text{Error}}} \).

Let's denote:

  • C = df Treatment
  • A = SS Error
  • E = df Error
  • B = SS Total
  • F = F-statistic value for Treatment (we need to calculate this)
  • G = table F-value at the critical level.

In the provided ANOVA table, we have certain values:

  • SS Treatment = 12,689
  • F-statistic = 10.6642
  • Total df = 11

To proceed:

  1. Find the total sum of squares (B): \[ SS_{\text{Total}} = SS_{\text{Treatment}} + SS_{\text{Error}} \quad \Rightarrow \quad B = 12,689 + A. \]

  2. Determine the degrees of freedom for error (E) and the total degrees of freedom (11): \[ C + E = 11. \]

Given that \( MS_{\text{Error}} = 595.3611 \): \[ MS_{\text{Error}} = \frac{A}{E} \quad \Rightarrow \quad A = 595.3611 \times E. \]

We know \( MS_{\text{Treatment}} \) is calculated as follows: \[ MS_{\text{Treatment}} = \frac{12,689}{C}. \]

And F-statistic can be expressed as: \[ F = \frac{MS_{\text{Treatment}}}{MS_{\text{Error}}}. \] Substituting: \[ 10.6642 = \frac{\frac{12,689}{C}}{595.3611}. \] Solving for \( C \): \[ 10.6642 \times 595.3611 = \frac{12,689}{C}, \] \[ 6355.287537 = \frac{12,689}{C}, \] \[ C = \frac{12,689}{6355.287537} \approx 2. \]

So, the value of C is 2.