ASI.AMMI computes the AMMI Stability Index (ASI) (Jambhulkar et al. 2014; Jambhulkar et al. 2015; Jambhulkar et al. 2017) considering the first two interaction principal components (IPCs) in the AMMI model. Using ASI, the Simultaneous Selection Index for Yield and Stability (SSI) is also calculated according to the argument ssi.method.

ASI.AMMI(model, ssi.method = c("farshadfar", "rao"), a = 1)

Arguments

model

The AMMI model (An object of class AMMI generated by AMMI).

ssi.method

The method for the computation of simultaneous selection index. Either "farshadfar" or "rao" (See SSI).

a

The ratio of the weights given to the stability components for computation of SSI when method = "rao" (See SSI).

Value

A data frame with the following columns:

ASI

The ASI values.

SSI

The computed values of simultaneous selection index for yield and stability.

rASI

The ranks of ASI values.

rY

The ranks of the mean yield of genotypes.

means

The mean yield of the genotypes.

The names of the genotypes are indicated as the row names of the data frame.

Details

The AMMI Stability Index (\(ASI\)) (Jambhulkar et al. 2014; Jambhulkar et al. 2015; Jambhulkar et al. 2017) is computed as follows:

\[ASI = \sqrt{\left [ PC_{1}^{2} \times \theta_{1}^{2} \right ]+\left [ PC_{2}^{2} \times \theta_{2}^{2} \right ]}\]

Where, \(PC_{1}\) and \(PC_{2}\) are the scores of 1st and 2nd IPCs respectively; and \(\theta_{1}\) and \(\theta_{2}\) are percentage sum of squares explained by the 1st and 2nd principal component interaction effect respectively.

References

Jambhulkar NN, Bose LK, Pande K, Singh ON (2015). “Genotype by environment interaction and stability analysis in rice genotypes.” Ecology, Environment and Conservation, 21(3), 1427--1430.

Jambhulkar NN, Bose LK, Singh ON (2014). “AMMI stability index for stability analysis.” In Mohapatra T (ed.), CRRI Newsletter, January-March 2014, volume 35(1), 15. Central Rice Research Institute, Cuttack, Orissa.

Jambhulkar NN, Rath NC, Bose LK, Subudhi HN, Biswajit M, Lipi D, Meher J (2017). “Stability analysis for grain yield in rice in demonstrations conducted during rabi season in India.” Oryza, 54(2), 236--240.

See also

Examples

library(agricolae)
data(plrv)

# AMMI model
model <- with(plrv, AMMI(Locality, Genotype, Rep, Yield, console = FALSE))

# ANOVA
model$ANOVA
#> Analysis of Variance Table
#> 
#> Response: Y
#>            Df Sum Sq Mean Sq  F value    Pr(>F)    
#> ENV         5 122284 24456.9 257.0382  9.08e-12 ***
#> REP(ENV)   12   1142    95.1   2.5694  0.002889 ** 
#> GEN        27  17533   649.4  17.5359 < 2.2e-16 ***
#> ENV:GEN   135  23762   176.0   4.7531 < 2.2e-16 ***
#> Residuals 324  11998    37.0                       
#> ---
#> Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1

# IPC F test
model$analysis
#>     percent  acum Df     Sum.Sq   Mean.Sq F.value   Pr.F
#> PC1    56.3  56.3 31 13368.5954 431.24501   11.65 0.0000
#> PC2    27.1  83.3 29  6427.5799 221.64069    5.99 0.0000
#> PC3     9.4  92.7 27  2241.9398  83.03481    2.24 0.0005
#> PC4     4.3  97.1 25  1027.5785  41.10314    1.11 0.3286
#> PC5     2.9 100.0 23   696.1012  30.26527    0.82 0.7059

# Mean yield and IPC scores
model$biplot
#>         type    Yield         PC1          PC2         PC3         PC4
#> 102.18   GEN 26.31947 -1.50828851  1.258765244 -0.19220309  0.48738861
#> 104.22   GEN 31.28887  0.32517729 -1.297024517 -0.63695749 -0.44159957
#> 121.31   GEN 30.10174  0.95604605  1.143461054 -1.28777348  2.22246913
#> 141.28   GEN 39.75624  2.11153737  0.817810467  1.45527701  0.25257620
#> 157.26   GEN 36.95181  1.05139017  2.461179974 -1.97208942 -1.96538800
#> 163.9    GEN 21.41747 -2.12407441 -0.284381234 -0.21791137 -0.50743629
#> 221.19   GEN 22.98480 -0.84981828  0.347983673 -0.82400783 -0.11451944
#> 233.11   GEN 28.66655  0.07554203 -1.046497338  1.04040485  0.22868362
#> 235.6    GEN 38.63477  1.20102029 -2.816581184  0.80975361  1.02013062
#> 241.2    GEN 26.34039 -0.79948495  0.220768053 -0.98538801  0.30004421
#> 255.7    GEN 30.58975 -1.49543817 -1.186549449  0.92552519 -0.32009239
#> 314.12   GEN 28.17335  1.39335380 -0.332786322 -0.73226877  0.05987348
#> 317.6    GEN 35.32583  1.05170769  0.002555823 -0.81561907  0.58180433
#> 319.20   GEN 38.75767  3.08338144  1.995946966  0.87971668 -1.11908943
#> 320.16   GEN 26.34808 -1.55737097  0.732314249 -0.41432567  1.32097009
#> 342.15   GEN 26.01336 -1.35880873 -0.741980068  0.87480105 -1.12013125
#> 346.2    GEN 23.84175 -2.48453928 -0.397045286  1.07091711 -0.90974484
#> 351.26   GEN 36.11581  1.22670345  1.537183139  1.79835728 -0.03516368
#> 364.21   GEN 34.05974  0.27328985 -0.447941156  0.03139543  0.77920500
#> 402.7    GEN 27.47748 -0.12907269 -0.080086669  0.01934016 -0.36085862
#> 405.2    GEN 28.98663 -1.90936369  0.309047963  0.57682642  0.51163370
#> 406.12   GEN 32.68323  0.90781100 -1.733433781 -0.24223050 -0.38596144
#> 427.7    GEN 36.19020  0.42791957 -0.723190970 -0.85381724 -0.53089914
#> 450.3    GEN 36.19602  1.38026196  1.279525147  0.16025163  0.61270137
#> 506.2    GEN 33.26623 -0.33054261 -0.302588536 -1.58471588 -0.04659416
#> Canchan  GEN 27.00126  1.47802905  0.380553178  1.67423900  0.07718375
#> Desiree  GEN 16.15569 -3.64968796  1.720025405  0.43761089  0.04648011
#> Unica    GEN 39.10400  1.25331924 -2.817033826 -0.99510845 -0.64366599
#> Ayac     ENV 23.70254 -2.29611851  0.966037760  1.95959116  2.75548057
#> Hyo-02   ENV 45.73082  3.85283195 -5.093371615  1.16967118 -0.08985538
#> LM-02    ENV 34.64462 -1.14575146 -0.881093222 -4.56547274  0.55159099
#> LM-03    ENV 53.83493  5.34625518  4.265275487 -0.14143931 -0.11714533
#> SR-02    ENV 14.95128 -2.58678337  0.660309540  0.89096920 -3.25055305
#> SR-03    ENV 11.15328 -3.17043379  0.082842050  0.68668051  0.15048221
#>                 PC5
#> 102.18  -0.04364115
#> 104.22   0.95312506
#> 121.31  -1.30661916
#> 141.28  -0.25996142
#> 157.26  -0.59719268
#> 163.9    0.18563390
#> 221.19  -0.57504816
#> 233.11   0.65754266
#> 235.6   -0.40273415
#> 241.2    0.07555258
#> 255.7   -0.46344763
#> 314.12   0.54406154
#> 317.6    0.39627052
#> 319.20   0.29657050
#> 320.16   2.29506737
#> 342.15  -0.10776433
#> 346.2   -0.12738693
#> 351.26   0.30191335
#> 364.21  -0.95811256
#> 402.7   -0.28473777
#> 405.2   -0.34397623
#> 406.12  -0.49796296
#> 427.7    1.00677993
#> 450.3   -0.34325251
#> 506.2    0.87807441
#> Canchan  0.49381313
#> Desiree -0.86767477
#> Unica   -0.90489253
#> Ayac     1.67177210
#> Hyo-02   0.01540152
#> LM-02    0.52350416
#> LM-03   -0.40285728
#> SR-02    1.37283488
#> SR-03   -3.18065538

# G*E matrix (deviations from mean)
array(model$genXenv, dim(model$genXenv), dimnames(model$genXenv))
#>          ENV
#> GEN              Ayac      Hyo-02       LM-02       LM-03        SR-02
#>   102.18    5.5726162 -12.4918224   1.7425251  -2.7070438   2.91734869
#>   104.22   -2.8712076   7.1684102   3.9336218  -4.0358373   0.47881580
#>   121.31    0.3255230  -3.8666836   4.3182811  10.4366135 -11.88343843
#>   141.28   -0.9451837   5.6454825  -9.7806639  14.6463104  -4.80337115
#>   157.26  -10.3149711 -10.6241677   4.2336365  16.8683612   2.71710210
#>   163.9     3.0874931  -6.9416721   3.4963790 -12.5533271   7.01688164
#>   221.19   -0.6041752  -6.0090018   4.0648518  -2.6974743   1.27671246
#>   233.11    2.5837535   6.8277609  -3.4440645  -4.4985717   0.19989490
#>   235.6    -1.7541523  19.8225025  -2.2394463  -5.6643239  -8.11400542
#>   241.2     1.0710975  -5.3831118   5.4253097  -3.2588271   0.46433086
#>   255.7     2.4443155   1.3860497  -1.8857757 -12.9626594   4.31373929
#>   314.12   -3.8812099   6.2098482   2.3577759   5.9071782  -3.92419060
#>   317.6    -1.7450319   3.0388540   3.0448064   5.5211634  -4.79271565
#>   319.20   -6.0155949   2.8477540  -9.7697504  24.8850017  -1.82949467
#>   320.16   10.9481796 -10.2982108   4.9608280  -6.2233088   2.99984918
#>   342.15    0.8508002  -0.3338618  -2.4575390 -10.3783871   7.29753151
#>   346.2     4.7000495  -6.2178087  -2.2612391 -14.9700672   9.90123888
#>   351.26    2.6002030  -0.9918665 -10.8315931  12.7429121  -0.02713985
#>   364.21   -0.4533734   3.2864208  -0.1335527  -0.1592533  -4.82292664
#>   402.7    -1.2134573  -0.0387229  -0.2179557  -0.8774011   1.08032472
#>   405.2     6.6477681  -8.3071271  -0.6159895  -8.8927189   3.52179705
#>   406.12   -6.1296667  12.0703469   1.1195092  -2.2601009  -3.13776595
#>   427.7    -3.1340922   4.3967072   4.2792028  -1.0194744   0.76266844
#>   450.3    -0.5047010  -1.0720791  -3.2821761  12.8806007  -5.04562407
#>   506.2    -1.2991912  -1.5682154   8.3142802  -3.1819279   0.60021498
#>   Canchan   1.2929442   5.7152780  -9.3713622   9.0803035  -1.65332869
#>   Desiree   9.5767845 -22.3280421   0.2396387 -11.8935722   9.62433886
#>   Unica   -10.8355195  18.0569790   4.7604622  -4.7341684  -5.13878822
#>          ENV
#> GEN             SR-03
#>   102.18    4.9663762
#>   104.22   -4.6738028
#>   121.31    0.6697043
#>   141.28   -4.7625741
#>   157.26   -2.8799609
#>   163.9     5.8942454
#>   221.19    3.9690870
#>   233.11   -1.6687730
#>   235.6    -2.0505746
#>   241.2     1.6812008
#>   255.7     6.7043306
#>   314.12   -6.6694018
#>   317.6    -5.0670763
#>   319.20  -10.1179157
#>   320.16   -2.3873373
#>   342.15    5.0214562
#>   346.2     8.8478267
#>   351.26   -3.4925156
#>   364.21    2.2826853
#>   402.7     1.2672123
#>   405.2     7.6462704
#>   406.12   -1.6623226
#>   427.7    -5.2850119
#>   450.3    -2.9760204
#>   506.2    -2.8651608
#>   Canchan  -5.0638348
#>   Desiree  14.7808522
#>   Unica    -2.1089651

# With default ssi.method (farshadfar)
ASI.AMMI(model)
#>                ASI SSI rASI rY    means
#> 102.18  0.91512303  43   20 23 26.31947
#> 104.22  0.39631322  19    6 13 31.28887
#> 121.31  0.62108102  25   10 15 30.10174
#> 141.28  1.20927797  26   25  1 39.75624
#> 157.26  0.89176583  22   17  5 36.95181
#> 163.9   1.19833464  51   24 27 21.41747
#> 221.19  0.48765291  34    8 26 22.98480
#> 233.11  0.28677206  21    4 17 28.66655
#> 235.6   1.01971997  25   21  4 38.63477
#> 241.2   0.45406877  29    7 22 26.34039
#> 255.7   0.90124720  33   19 14 30.58975
#> 314.12  0.78962523  30   12 18 28.17335
#> 317.6   0.59211183  18    9  9 35.32583
#> 319.20  1.81826161  30   27  3 38.75767
#> 320.16  0.89897900  39   18 21 26.34808
#> 342.15  0.79099371  37   13 24 26.01336
#> 346.2   1.40292793  51   26 25 23.84175
#> 351.26  0.80654291  22   14  8 36.11581
#> 364.21  0.19598368  12    2 10 34.05974
#> 402.7   0.07583976  20    1 19 27.47748
#> 405.2   1.07822942  39   23 16 28.98663
#> 406.12  0.69418710  23   11 12 32.68323
#> 427.7   0.31056699  12    5  7 36.19020
#> 450.3   0.85094150  22   16  6 36.19602
#> 506.2   0.20336120  14    3 11 33.26623
#> Canchan 0.83849670  35   15 20 27.00126
#> Desiree 2.10698168  56   28 28 16.15569
#> Unica   1.03956820  24   22  2 39.10400

# With  ssi.method = "rao"
ASI.AMMI(model, ssi.method = "rao")
#>                ASI       SSI rASI rY    means
#> 102.18  0.91512303 1.3832387   20 23 26.31947
#> 104.22  0.39631322 2.2326416    6 13 31.28887
#> 121.31  0.62108102 1.7551519   10 15 30.10174
#> 141.28  1.20927797 1.6936286   25  1 39.75624
#> 157.26  0.89176583 1.7436656   17  5 36.95181
#> 163.9   1.19833464 1.0993106   24 27 21.41747
#> 221.19  0.48765291 1.7347850    8 26 22.98480
#> 233.11  0.28677206 2.6102708    4 17 28.66655
#> 235.6   1.01971997 1.7309273   21  4 38.63477
#> 241.2   0.45406877 1.9170753    7 22 26.34039
#> 255.7   0.90124720 1.5305578   19 14 30.58975
#> 314.12  0.78962523 1.5271379   12 18 28.17335
#> 317.6   0.59211183 1.9633384    9  9 35.32583
#> 319.20  1.81826161 1.5279859   27  3 38.75767
#> 320.16  0.89897900 1.3936010   18 21 26.34808
#> 342.15  0.79099371 1.4556573   13 24 26.01336
#> 346.2   1.40292793 1.1198795   26 25 23.84175
#> 351.26  0.80654291 1.7733422   14  8 36.11581
#> 364.21  0.19598368 3.5623227    2 10 34.05974
#> 402.7   0.07583976 7.2317748    1 19 27.47748
#> 405.2   1.07822942 1.3907733   23 16 28.98663
#> 406.12  0.69418710 1.7578467   11 12 32.68323
#> 427.7   0.31056699 2.7272047    5  7 36.19020
#> 450.3   0.85094150 1.7448731   16  6 36.19602
#> 506.2   0.20336120 3.4475042    3 11 33.26623
#> Canchan 0.83849670 1.4534532   15 20 27.00126
#> Desiree 2.10698168 0.7548219   28 28 16.15569
#> Unica   1.03956820 1.7372299   22  2 39.10400

# Changing the ratio of weights for Rao's SSI
ASI.AMMI(model, ssi.method = "rao", a = 0.43)
#>                ASI       SSI rASI rY    means
#> 102.18  0.91512303 1.0839450   20 23 26.31947
#> 104.22  0.39631322 1.5415455    6 13 31.28887
#> 121.31  0.62108102 1.3141619   10 15 30.10174
#> 141.28  1.20927797 1.4671376   25  1 39.75624
#> 157.26  0.89176583 1.4365328   17  5 36.95181
#> 163.9   1.19833464 0.8707513   24 27 21.41747
#> 221.19  0.48765291 1.1731344    8 26 22.98480
#> 233.11  0.28677206 1.6551898    4 17 28.66655
#> 235.6   1.01971997 1.4623334   21  4 38.63477
#> 241.2   0.45406877 1.3138836    7 22 26.34039
#> 255.7   0.90124720 1.2266562   19 14 30.58975
#> 314.12  0.78962523 1.1802765   12 18 28.17335
#> 317.6   0.59211183 1.5007728    9  9 35.32583
#> 319.20  1.81826161 1.3773527   27  3 38.75767
#> 320.16  0.89897900 1.0889326   18 21 26.34808
#> 342.15  0.79099371 1.1093959   13 24 26.01336
#> 346.2   1.40292793 0.9246517   26 25 23.84175
#> 351.26  0.80654291 1.4337564   14  8 36.11581
#> 364.21  0.19598368 2.1648057    2 10 34.05974
#> 402.7   0.07583976 3.6203374    1 19 27.47748
#> 405.2   1.07822942 1.1367545   23 16 28.98663
#> 406.12  0.69418710 1.3632981   11 12 32.68323
#> 427.7   0.31056699 1.8452998    5  7 36.19020
#> 450.3   0.85094150 1.4230055   16  6 36.19602
#> 506.2   0.20336120 2.1006861    3 11 33.26623
#> Canchan 0.83849670 1.1268084   15 20 27.00126
#> Desiree 2.10698168 0.6248300   28 28 16.15569
#> Unica   1.03956820 1.4737642   22  2 39.10400