Stability

The Stability tab is shown below:

The Stability tab contains the following elements:

One Overlay Plot plot.

This plot displays various stability measures for each genotype, with the value of the stability measure represented on the y-axis. The six measures that are displayed are described in the following table:

:

Stability Measure	Definition
W_i	Wricke’s ecovalence is determined using the formula: The closer this value is to 0, the more stable the effect. This measure is highly correlated with MSD_i.
Beta_i1	Regression Coefficient. The closer this value is to 1, the more stable the effect.
MSD_i	Pooled Deviation of E and GxE nonlinear components, broken out by genotype. Differs from S2d_i by a constant.
S2d_i	Mean Square Deviation from Regression. The closer this value is to 0, the more stable the effect.
Alpha_i2	Linear response of trait to environmental effects.
Lambda_i	Deviation from the linear response in terms of error variance.

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1

Eberhart and Russell's measures (Betai, S2d , and MSDi) are considered together. Stable varieties occur when Betai is near 1 and S2d is near 0.

2

Tai’s measures (Alphai and Lambdai) are considered together. Average stability is indicated when Alphai=0 and Lambdai=1. Perfect stability is indicated when Alphai=-1 and Lambdai=1.

Stability Point

The Stability Point tab is shown below:

This graph displays a series of estimated numbers of ancestral populations and their respective estimated variances for varying threshold values. This graph can be used to help determining the number of ancestral populations when this parameter is unknown. The second region from the left to right where the variance flattens down and finds a minimum is considered a good estimate for the number of ancestral populations.

See Scree Plot for more information.