The problem of bias persists in the deep learning community as models continue to provide disparate performance across different demographic subgroups. Therefore, several algorithms have been proposed to improve the fairness of deep models. However, a majority of these algorithms utilize the protected attribute information for bias mitigation, which severely limits their application in real-world scenarios. To address this concern, we have proposed a novel algorithm, termed as Non-Protected Attribute-based Debiasing (NPAD) algorithm for bias mitigation, that does not require the protected attribute information. The proposed NPAD algorithm utilizes the auxiliary information provided by the non-protected attributes to optimize the model for bias mitigation. Further, two different loss functions, Debiasing via Attribute Cluster Loss (DACL) and Filter Redundancy Loss (FRL) have been proposed to optimize the model for fairness goals. Multiple experiments are performed on the LFWA and CelebA datasets for facial attribute prediction, and a significant reduction in bias across different gender and age subgroups is observed.
Figures & tables
Figure 1: Illustration of model training using (a) conventional approaches, (b) conventional debiasing approaches, and (c) proposed Non-Protected Attribute-based Debiasing (NPAD) algorithm. The proposed algorithm does not require the protected attribute information for bias mitigation.
Figure 2: Block diagram illustrating model training using the proposed NPAD algorithm. In the first stage, disparity is computed by evaluating the model trained for predicting attribute Ai across the classes of other non-protected attributes. Next, the non-protected attributes are selected based on the disparity and independence. In the second stage, model is optimized using the proposed DACL and FRL functions for bias mitigation.
Figure 3: A toy example of the feature visualization of a model trained for shape prediction on the testing set. Solid and Dotted represent classes of the non-protected attribute and Color represents the protected attribute. (a) Shows the biased feature representations of the model (trained using conventional approaches). (b) Shows the unbiased feature representations of the model (trained using the proposed NPAD algorithm). (c) Shows the unbiased feature representations of the model across the unknown protected attribute (assuming the non-protected attribute is fully correlated with the protected attribute).
Figure 4: Sample images of the (a) LFWA [ 29 ] and (b) CelebA [ 30 ] datasets. Images of both datasets are collected in unconstrained environmental settings with variation in pose, illumination, and the degree of occlusion.
Algorithm
PM ( Predicted )
PNM ( Predicted )
Ground Truth
B
NB
B
NB
BMT
B
0
766
0
363
NB
0
4654
0
1097
NPAD (One)
B
553
213
292
71
NB
253
4401
62
1035
NPAD (Two)
B
511
255
289
74
Table 1: Confusion matrix for ‘Bangs’ prediction (Bangs as ‘B’ and Not Bangs as ‘NB’) across gender subgroups on the LFWA dataset.
Attribute
Algorithm
Across Gender
Across Age
Accuracy ↑
DoB ↓
OPE ↓
Accuracy ↑
DoB ↓
OPE ↓
PM
PNM
Overall
PY
PNY
Overall
Big Nose
BMT
77.93
75.21
77.35
1.36
2.73
68.78
79.55
77.35
5.38
10.77
PAD
83.21
82.47
83.05
0.37
0.74
80.26
84.15
83.36
1.94
3.90
LfF
81.01
77.94
80.36
1.53
3.07
75.19
81.69
80.36
3.24
6.49
NPAD (One)
82.99
81.92
82.76
0.53
1.07
78.62
83.82
82.76
2.60
5.21
Table 2: Performance of the proposed NPAD algorithm (%) on three attributes of the LFWA dataset. The result closest to PAD is highlighted in bold.
Figure 5: t-SNE visualization using BMT (top row) and the proposed NPAD algorithm (bottom row) corresponding to attributes ‘Big Nose’ and ‘Black Hair’ of the LFWA dataset.
Attribute
Algorithm
Across Gender
Across Age
Accuracy ↑
DoB ↓
OPE ↓
Accuracy ↑
DoB ↓
OPE ↓
PM
PNM
Overall
PY
PNY
Overall
Wearing Necktie
BMT
81.97
99.93
92.99
8.98
17.96
96.86
80.94
92.99
7.96
15.92
PAD
91.29
99.90
96.57
4.30
8.61
98.25
92.53
96.86
2.86
5.71
LfF
81.97
99.93
92.99
8.98
17.96
96.86
80.94
92.99
7.96
15.92
NPAD (One)
90.71
99.89
96.34
4.59
9.19
97.93
91.40
96.34
3.26
6.53
Table 3: Performance of the proposed NPAD algorithm (%) on three attributes of the CelebA dataset. The result closest to PAD is highlighted in bold.
Attribute
First Non-protected Attribute
Second Non-protected Attribute
Wearing Necktie
0.19
0.42
Sideburns
0.79
0.02
Gray Hair
0.11
0.07
Table 4: Correlation between the non-protected attributes used for debiasing with the protected attribute ‘Gender.’
Figure 6: Mean overall classification accuracy corresponding to all the attributes (excluding male and young ) using BMT, PAD, LfF, and NPAD algorithms on the LFWA and CelebA datasets. PAD (Gender) and PAD (Age) indicates the performance when optimization is done using gender and age information, respectively.
Figure 7: Mean DoB and mean OPE corresponding to all the attributes (excluding male and young ) using BMT, PAD, LfF, and NPAD algorithm on the (a) LFWA and (b) CelebA datasets.
BMT
NPAD (One)
NPAD (Two)
LFWA
8.64
6.40
6.25
CelebA
8.39
7.12
7.03
Table 5: Mean OPE (%) for all the attributes (excluding male and young) on the LFWA and CelebA datasets across the intersectional subgroups of gender and age .
Figure 8: Cross dataset experiment: mean OPE (%) corresponding to all the attributes (excluding male and young) using BMT and NPAD on (a) LFWA and (b) CelebA datasets.
Figure 9: Mean DoB and mean OPE of the case studies corresponding to the three attributes of the CelebA dataset across gender subgroups. Comparison is performed with mean NPAD.
Figure 10: Overall accuracy of the case studies corresponding to the three attributes of the LFWA dataset. Comparison is performed with mean NPAD.
Loss
Accuracy ↑
DoB ↓
OPE ↓
PM
PNM
Overall
DACL
82.86
81.23
82.51
0.81
1.63
FRL
78.93
76.10
78.33
1.41
2.83
Proposed
82.99
81.92
82.76
0.53
1.07
Table 6: Performance of the model (%) by ablating individual loss terms of the NPAD algorithm (one attribute) for ‘Big Nose’ prediction on the LFWA dataset across different gender subgroups.
Figure 11: DoB and OPE of the model when the independence between non-protected attributes is not considered. The performance is shown for ‘Black Hair’ prediction across age subgroups on the LFWA dataset.
Algo
DoB ↓
OPE ↓
Overall Accuracy ↑
Gender
Age
Gender
Age
ARL
4.70
3.34
9.41
6.68
80.33
Proposed
3.67
2.51
7.35
5.03
84.50
Table 7: Comparison with existing algorithm on the LFWA dataset. Average over all attributes (excluding protected attributes - male and young) is reported.
School of Civil Engineering, Universidad Politecnica de Madrid, Profesor Aranguren 3, Madrid, 28040, Spain. · Bain&Company, Velazquez, Madrid, 28006, Spain.