Statistical modelling/Analysis of variance

The analysis of variance table demonstrates that the effect of sucrose on percentage germination (m_pgerm) is statistically significant (large variance ratio value). 

The pattern in mean percentage germination values shows the parabolic pattern indicated earlier. The slight differences in mean values for individual concentrations from those depicted in the descriptive statistics table shown earlier are due to the few missing values which have been estimated.

By examining the polynomial terms in the analysis of variance it can be seen from the size of variance ratio values that both linear and quadratic terms, but not cubic, are significant. 

Interestingly, there is no significant variation in bud length indicating that bud lengths between 20 to 22 mm range has no effect on germination rate. However, there is some variation among individual buds, although, based on the few buds sampled, it is not significant.

 
**** Analysis of variance *****
 
Variate: m_pgerm
Source of variation

d.f

s.s.

m.s.

v.r.

length stratum

2

150.57

75.28

0.43

length.bud stratum

3

524.32

174.77

1.82

 length.bud.slide stratum
sucros

7

15548.17

2221.17

23.17

  Lin

1

9784.53

9784.53

102.06

  Quad

1

5170.69

5170.69

53.93

  Cub

1

19.27

19.27

0.20

Deviations

4

573.67

143.42

1.50

Residual

35

3355.50

95.87

 
Total

47

19578.55

   

*** Tables of means ***
sucros 0.0 5.0 10.0 15.0 20.0 25.0 30.0
5.3 19.9 36.1 52.6 58.3 50.7 58.3
sucros 35.0            
  45.6            

***Standard errors of differences of means***
Table

sucros

rep.

6

d.f

35

s.e.d

5.653

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