stability.er {agrostab} | R Documentation |
This function calculates the Erberhart&Rassel's stability parameters and the Dragavtsev's coefficient of multiplicativity.
stability.er(dataf, res_var, gen_var, env_var, rep_var, plotIt = TRUE)
dataf |
the name of the data frame containing the data to analyze. |
res_var |
the response variable. |
gen_var |
the genotypes variable. |
env_var |
the environments variable. |
rep_var |
the replications variable. |
plotIt |
a logical value specifying if plot should be drawn; default is TRUE |
Returns a list of three objects:
the analysis of variance table
the data frame object of stability analysis results:
bi
regression of genotype means on environmental index
t_value
t-values for gypothesis that bi=1
p_value
p-values for gypothesis that bi=1
s2di
individual squared deviation from regression
pf_value
p-values for gypothesis that s2di=0
ai
Dragavtsev's coefficient of multiplicativity
enviromental indexes
Eberhart, S.A. and W.A. Russell. 1966. Stability parameters for comparing varieties. Crop Sci 6: 36-40. doi:10.2135/cropsci1966.0011183X000600010011x
data(exp_data)
stability.er(exp_data,"yield","gen","env","rep")