ASTAB.AMMI computes the AMMI Based Stability Parameter (ASTAB) (Rao and Prabhakaran 2005) considering all significant interaction principal components (IPCs) in the AMMI model. Using ASTAB, the Simultaneous Selection Index for Yield and Stability (SSI) is also calculated according to the argument ssi.method.

ASTAB.AMMI(model, n, alpha = 0.05, ssi.method = c("farshadfar", "rao"), a = 1)

Arguments

model

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

n

The number of principal components to be considered for computation. The default value is the number of significant IPCs.

alpha

Type I error probability (Significance level) to be considered to identify the number of significant IPCs.

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:

ASTAB

The ASTAB values.

SSI

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

rASTAB

The ranks of ASTAB 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 Based Stability Parameter value (\(ASTAB\)) (Rao and Prabhakaran 2005) is computed as follows:

\[ASTAB = \sum_{n=1}^{N'}\lambda_{n}\gamma_{in}^{2}\]

Where, \(N'\) is the number of significant IPCs (number of IPC that were retained in the AMMI model via F tests); \(\lambda_{n}\) is the singular value for \(n\)th IPC and correspondingly \(\lambda_{n}^{2}\) is its eigen value; and \(\gamma_{in}\) is the eigenvector value for \(i\)th genotype.

References

Rao AR, Prabhakaran VT (2005). “Use of AMMI in simultaneous selection of genotypes for yield and stability.” Journal of the Indian Society of Agricultural Statistics, 59, 76--82.

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 n (N') and default ssi.method (farshadfar)
ASTAB.AMMI(model)
#>               ASTAB SSI rASTAB rY    means
#> 102.18   3.89636621  39     16 23 26.31947
#> 104.22   2.19372771  21      8 13 31.28887
#> 121.31   3.87988776  29     14 15 30.10174
#> 141.28   7.24523520  23     22  1 39.75624
#> 157.26  11.05196482  31     26  5 36.95181
#> 163.9    4.64005014  46     19 27 21.41747
#> 221.19   1.52227265  30      4 26 22.98480
#> 233.11   2.18330553  24      7 17 28.66655
#> 235.6   10.03128021  28     24  4 38.63477
#> 241.2    1.65890425  27      5 22 26.34039
#> 255.7    4.50083178  32     18 14 30.58975
#> 314.12   2.58839912  27      9 18 28.17335
#> 317.6    1.77133006  15      6  9 35.32583
#> 319.20  14.26494686  30     27  3 38.75767
#> 320.16   3.13335427  32     11 21 26.34808
#> 342.15   3.16217247  36     12 24 26.01336
#> 346.2    7.47744386  48     23 25 23.84175
#> 351.26   7.10182225  29     21  8 36.11581
#> 364.21   0.27632429  12      2 10 34.05974
#> 402.7    0.02344768  20      1 19 27.47748
#> 405.2    4.07390905  33     17 16 28.98663
#> 406.12   3.88758910  27     15 12 32.68323
#> 427.7    1.43512423  10      3  7 36.19020
#> 450.3    3.56798827  19     13  6 36.19602
#> 506.2    2.71214267  21     10 11 33.26623
#> Canchan  5.13246683  40     20 20 27.00126
#> Desiree 16.47021287  56     28 28 16.15569
#> Unica   10.49672952  27     25  2 39.10400

# With n = 4 and default ssi.method (farshadfar)
ASTAB.AMMI(model, n = 4)
#>              ASTAB SSI rASTAB rY    means
#> 102.18   4.1339139  36     13 23 26.31947
#> 104.22   2.3887379  21      8 13 31.28887
#> 121.31   8.8192568  38     23 15 30.10174
#> 141.28   7.3090299  22     21  1 39.75624
#> 157.26  14.9147148  31     26  5 36.95181
#> 163.9    4.8975417  45     18 27 21.41747
#> 221.19   1.5353874  29      3 26 22.98480
#> 233.11   2.2356017  24      7 17 28.66655
#> 235.6   11.0719467  29     25  4 38.63477
#> 241.2    1.7489308  27      5 22 26.34039
#> 255.7    4.6032909  30     16 14 30.58975
#> 314.12   2.5919840  27      9 18 28.17335
#> 317.6    2.1098263  15      6  9 35.32583
#> 319.20  15.5173080  30     27  3 38.75767
#> 320.16   4.8783163  38     17 21 26.34808
#> 342.15   4.4168665  39     15 24 26.01336
#> 346.2    8.3050795  47     22 25 23.84175
#> 351.26   7.1030587  28     20  8 36.11581
#> 364.21   0.8834847  12      2 10 34.05974
#> 402.7    0.1536666  20      1 19 27.47748
#> 405.2    4.3356781  30     14 16 28.98663
#> 406.12   4.0365553  24     12 12 32.68323
#> 427.7    1.7169781  11      4  7 36.19020
#> 450.3    3.9433912  17     11  6 36.19602
#> 506.2    2.7143137  21     10 11 33.26623
#> Canchan  5.1384242  39     19 20 27.00126
#> Desiree 16.4723733  56     28 28 16.15569
#> Unica   10.9110354  26     24  2 39.10400

# With default n (N') and ssi.method = "rao"
ASTAB.AMMI(model, ssi.method = "rao")
#>               ASTAB        SSI rASTAB rY    means
#> 102.18   3.89636621  0.9916073     16 23 26.31947
#> 104.22   2.19372771  1.2572096      8 13 31.28887
#> 121.31   3.87988776  1.1154972     14 15 30.10174
#> 141.28   7.24523520  1.3680406     22  1 39.75624
#> 157.26  11.05196482  1.2518822     26  5 36.95181
#> 163.9    4.64005014  0.8103867     19 27 21.41747
#> 221.19   1.52227265  1.0909958      4 26 22.98480
#> 233.11   2.18330553  1.1728390      7 17 28.66655
#> 235.6   10.03128021  1.3115430     24  4 38.63477
#> 241.2    1.65890425  1.1722749      5 22 26.34039
#> 255.7    4.50083178  1.1129205     18 14 30.58975
#> 314.12   2.58839912  1.1194868      9 18 28.17335
#> 317.6    1.77133006  1.4453573      6  9 35.32583
#> 319.20  14.26494686  1.3001667     27  3 38.75767
#> 320.16   3.13335427  1.0250358     11 21 26.34808
#> 342.15   3.16217247  1.0126098     12 24 26.01336
#> 346.2    7.47744386  0.8469106     23 25 23.84175
#> 351.26   7.10182225  1.2507915     21  8 36.11581
#> 364.21   0.27632429  2.9922101      2 10 34.05974
#> 402.7    0.02344768 23.0708927      1 19 27.47748
#> 405.2    4.07390905  1.0727560     17 16 28.98663
#> 406.12   3.88758910  1.1994027     15 12 32.68323
#> 427.7    1.43512423  1.5423074      3  7 36.19020
#> 450.3    3.56798827  1.3259199     13  6 36.19602
#> 506.2    2.71214267  1.2763780     10 11 33.26623
#> Canchan  5.13246683  0.9816986     20 20 27.00126
#> Desiree 16.47021287  0.5583351     28 28 16.15569
#> Unica   10.49672952  1.3245441     25  2 39.10400

# Changing the ratio of weights for Rao's SSI
ASTAB.AMMI(model, ssi.method = "rao", a = 0.43)
#>               ASTAB        SSI rASTAB rY    means
#> 102.18   3.89636621  0.9155436     16 23 26.31947
#> 104.22   2.19372771  1.1221097      8 13 31.28887
#> 121.31   3.87988776  1.0391104     14 15 30.10174
#> 141.28   7.24523520  1.3271348     22  1 39.75624
#> 157.26  11.05196482  1.2250659     26  5 36.95181
#> 163.9    4.64005014  0.7465140     19 27 21.41747
#> 221.19   1.52227265  0.8963051      4 26 22.98480
#> 233.11   2.18330553  1.0370941      7 17 28.66655
#> 235.6   10.03128021  1.2819982     24  4 38.63477
#> 241.2    1.65890425  0.9936194      5 22 26.34039
#> 255.7    4.50083178  1.0470721     18 14 30.58975
#> 314.12   2.58839912  1.0049865      9 18 28.17335
#> 317.6    1.77133006  1.2780410      6  9 35.32583
#> 319.20  14.26494686  1.2793904     27  3 38.75767
#> 320.16   3.13335427  0.9304495     11 21 26.34808
#> 342.15   3.16217247  0.9188855     12 24 26.01336
#> 346.2    7.47744386  0.8072751     23 25 23.84175
#> 351.26   7.10182225  1.2090596     21  8 36.11581
#> 364.21   0.27632429  1.9196572      2 10 34.05974
#> 402.7    0.02344768 10.4311581      1 19 27.47748
#> 405.2    4.07390905  1.0000071     17 16 28.98663
#> 406.12   3.88758910  1.1231672     15 12 32.68323
#> 427.7    1.43512423  1.3357940      3  7 36.19020
#> 450.3    3.56798827  1.2428556     13  6 36.19602
#> 506.2    2.71214267  1.1671018     10 11 33.26623
#> Canchan  5.13246683  0.9239540     20 20 27.00126
#> Desiree 16.47021287  0.5403407     28 28 16.15569
#> Unica   10.49672952  1.2963093     25  2 39.10400