Q&A

아래는 GLM ANOVA 결과입니다.
두번째 layer_1 항목에 대해서 ** Denominator of F-test is zero라는 메세지가 나타나는
이유가 궁금합니다.

쉽게 생각하면 분모가 0이란 말은 잔차평균제곱합이 0이라는 뜻인가요?
이런 경우도 있는 건가요?
아님 제가 잘못 분석한건가요?

General Linear Model: crack_1 versus way_1, layer_1, month_1

Factor     Type     Levels  Values
way_1     fixed         2      1 2
layer_1    random     3      1 2 3
month_1  random     7      1 2 3 4 5 6 7

Analysis of Variance for crack_1, using Adjusted SS for Tests

Source                            DF     Seq SS     Adj SS     Adj MS      F      P
===========================================================================
way_1                              1       96.954       96.954      96.954   17.25   0.012 x
layer_1                             2       18.772       18.772        9.386      **
month_1                           6      132.367     132.367      22.061     3.54   0.086 x
way_1*layer_1                  2         0.208        0.208        0.104     0.10   0.905
way_1*month_1                 6       39.306      39.306        6.551     6.34   0.003
layer_1*month_1               12        8.489        8.489        0.707     0.68   0.739
way_1*layer_1*month_1    12       12.404      12.404        1.034     0.67   0.775
Error                             168      257.657     257.657       1.534
---------------------------------------------------------------------------
Total                             209      566.157  

x Not an exact F-test.

** Denominator of F-test is zero.

Unusual Observations for crack_1

Obs   crack_1       Fit      SE Fit  Residual   St Resid
44   12.6000   15.3200      0.5538   -2.7200     -2.46R
55   14.0000   17.4180      0.5538   -3.4180     -3.09R
69   14.4000   16.7400      0.5538   -2.3400     -2.11R
130   14.0000   16.3200      0.5538   -2.3200     -2.09R
135   13.1100   15.7820      0.5538   -2.6720     -2.41R
167   18.2900   15.9060      0.5538    2.3840      2.15R
201   17.4000   14.6400      0.5538    2.7600      2.49R
207   17.0000   14.7600      0.5538    2.2400      2.02R

Attachments

• crack(2001)_random.MPJ - 湲곗〈 寃쎈줈: ./files/attach/binaries/78415/834/011/8db908e7cf6d0bea159478c79afdeb21

Legacy document_srl: 11834 / Legacy URL: http://www.statedu.com/QnA/11834