Good performance metrics for multiclass classification problem besides accuracy?
If you can use python I suggest PyCM module. A vast variety of performance evaluation parameters is in access by this module and also you can use its documentation if you want to implement it by yourself.

There is an example of it:

&gt;&gt;&gt; from pycm import *
&gt;&gt;&gt; y_actu = [2, 0, 2, 2, 0, 1, 1, 2, 2, 0, 1, 2] # or y_actu = numpy.array([2, 0, 2, 2, 0, 1, 1, 2, 2, 0, 1, 2])
&gt;&gt;&gt; y_pred = [0, 0, 2, 1, 0, 2, 1, 0, 2, 0, 2, 2] # or y_pred = numpy.array([0, 0, 2, 1, 0, 2, 1, 0, 2, 0, 2, 2])
&gt;&gt;&gt; cm = ConfusionMatrix(actual_vector=y_actu, predict_vector=y_pred) # Create CM From Data
&gt;&gt;&gt; cm.classes
[0, 1, 2]
&gt;&gt;&gt; cm.table
{0: {0: 3, 1: 0, 2: 0}, 1: {0: 0, 1: 1, 2: 2}, 2: {0: 2, 1: 1, 2: 3}}
&gt;&gt;&gt; print(cm)
Predict          0        1        2        
Actual
0                3        0        0        
1                0        1        2        
2                2        1        3        




Overall Statistics : 

95% CI                                                           (0.30439,0.86228)
Bennett_S                                                        0.375
Chi-Squared                                                      6.6
Chi-Squared DF                                                   4
Conditional Entropy                                              0.95915
Cramer_V                                                         0.5244
Cross Entropy                                                    1.59352
Gwet_AC1                                                         0.38931
Joint Entropy                                                    2.45915
KL Divergence                                                    0.09352
Kappa                                                            0.35484
Kappa 95% CI                                                     (-0.07708,0.78675)
Kappa No Prevalence                                              0.16667
Kappa Standard Error                                             0.22036
Kappa Unbiased                                                   0.34426
Lambda A                                                         0.16667
Lambda B                                                         0.42857
Mutual Information                                               0.52421
Overall_ACC                                                      0.58333
Overall_RACC                                                     0.35417
Overall_RACCU                                                    0.36458
PPV_Macro                                                        0.56667
PPV_Micro                                                        0.58333
Phi-Squared                                                      0.55
Reference Entropy                                                1.5
Response Entropy                                                 1.48336
Scott_PI                                                         0.34426
Standard Error                                                   0.14232
Strength_Of_Agreement(Altman)                                    Fair
Strength_Of_Agreement(Cicchetti)                                 Poor
Strength_Of_Agreement(Fleiss)                                    Poor
Strength_Of_Agreement(Landis and Koch)                           Fair
TPR_Macro                                                        0.61111
TPR_Micro                                                        0.58333

Class Statistics :

Classes                                                          0                       1                       2                       
ACC(Accuracy)                                                    0.83333                 0.75                    0.58333                 
BM(Informedness or bookmaker informedness)                       0.77778                 0.22222                 0.16667                 
DOR(Diagnostic odds ratio)                                       None                    4.0                     2.0                     
ERR(Error rate)                                                  0.16667                 0.25                    0.41667                 
F0.5(F0.5 score)                                                 0.65217                 0.45455                 0.57692                 
F1(F1 score - harmonic mean of precision and sensitivity)        0.75                    0.4                     0.54545                 
F2(F2 score)                                                     0.88235                 0.35714                 0.51724                 
FDR(False discovery rate)                                        0.4                     0.5                     0.4                     
FN(False negative/miss/type 2 error)                             0                       2                       3                       
FNR(Miss rate or false negative rate)                            0.0                     0.66667                 0.5                     
FOR(False omission rate)                                         0.0                     0.2                     0.42857                 
FP(False positive/type 1 error/false alarm)                      2                       1                       2                       
FPR(Fall-out or false positive rate)                             0.22222                 0.11111                 0.33333                 
G(G-measure geometric mean of precision and sensitivity)         0.7746                  0.40825                 0.54772                 
LR+(Positive likelihood ratio)                                   4.5                     3.0                     1.5                     
LR-(Negative likelihood ratio)                                   0.0                     0.75                    0.75                    
MCC(Matthews correlation coefficient)                            0.68313                 0.2582                  0.16903                 
MK(Markedness)                                                   0.6                     0.3                     0.17143                 
N(Condition negative)                                            9                       9                       6                       
NPV(Negative predictive value)                                   1.0                     0.8                     0.57143                 
P(Condition positive)                                            3                       3                       6                       
POP(Population)                                                  12                      12                      12                      
PPV(Precision or positive predictive value)                      0.6                     0.5                     0.6                     
PRE(Prevalence)                                                  0.25                    0.25                    0.5                     
RACC(Random accuracy)                                            0.10417                 0.04167                 0.20833                 
RACCU(Random accuracy unbiased)                                  0.11111                 0.0434                  0.21007                 
TN(True negative/correct rejection)                              7                       8                       4                       
TNR(Specificity or true negative rate)                           0.77778                 0.88889                 0.66667                 
TON(Test outcome negative)                                       7                       10                      7                       
TOP(Test outcome positive)                                       5                       2                       5                       
TP(True positive/hit)                                            3                       1                       3                       
TPR(Sensitivity, recall, hit rate, or true positive rate)        1.0                     0.33333                 0.5  

&gt;&gt;&gt; cm.matrix()
Predict          0        1        2        
Actual
0                3        0        0        
1                0        1        2        
2                2        1        3        

&gt;&gt;&gt; cm.normalized_matrix()
Predict          0              1              2              
Actual
0                1.0            0.0            0.0            
1                0.0            0.33333        0.66667        
2                0.33333        0.16667        0.5