Research Article

Different Transfer Functions for Binary Particle Swarm Optimization with a New Encoding Scheme for Discounted {0-1} Knapsack Problem

Table 3

Comparison of 8 BPSO algorithms on SDKP1–SDKP10.

BPSO1BPSO2BPSO3BPSO4BPSO5BPSO6BPSO7BPSO8

SDKP1Best9104690103900678955894300944219441494363
AVE90484.489446.688655.588449.994089.394112.794174.494181.6
Worst8996488772878358784793687938079392093897
Std. dev240.44312.35513.73422.86152.07128.84103.15113.74
Gap4.215.316.146.360.390.370.300.29

SDKP2Best152080149910148440148320160470160490160430160570
AVE150627.7148857.0147307.0146598.3160058.0160033.3160127.0160136.0
Worst149590148000146410145830159730159380159480159780
Std. dev591.17505.77535.13595.93190.92237.35214.82182.33
Gap6.337.438.398.830.460.480.420.42

SDKP3Best225340222940220310218570237580237350237430237370
AVE223456.7221130.0218620.0217727.3236629.7236821.0236829.3236778.3
Worst222120219740217530217020235770236390236110235960
Std. dev617.52777.22567.24435.05359.95265.44352.00314.48
Gap6.217.188.248.610.680.600.600.62

SDKP4Best317610313630310850310020338360338480338520338240
AVE315521.0311837.3308411.3306979.7337381.0337525.0337545.0337433.0
Worst314020310180306940305490336270336540336440336210
Std. dev938.08789.991010.631074.09501.50524.94540.16495.98
Gap7.218.299.309.720.780.740.730.76

SDKP5Best438720431560427340425190459900459890460190459970
AVE435066.7429523.7424714.0422803.3458421.7458479.3458505.0458292.0
Worst432570427170422560421120456570456980457430457130
Std. dev1412.531057.971127.73833.64724.35669.22548.81802.76
Gap6.047.248.288.691.000.980.981.02

SDKP6Best428070424110417840415960463040462310463070462650
AVE424916.3420600.0415690.3413662.3461229.3461288.0461370.0461310.7
Worst423230418080414020412230459870459390459610459880
Std. dev1121.731370.311020.89994.05759.15708.60789.20680.64
Gap8.849.7610.8111.251.041.031.011.03

SDKP7Best580940574630567460562990615640615810615100614830
AVE578574.3571778.7564752.3561783.7613474.3613542.7613242.0613182.7
Worst576180569410563080560270611790611970611180610700
Std. dev1210.371118.881034.42708.71955.251000.74953.90984.83
Gap6.757.848.989.451.121.111.161.17

SDKP8Best619660613680605780602220665540665340665070665230
AVE616572.0609950.0603096.3600201.3663894.7663703.3663633.7663681.7
Worst614660607940601290598950662710661970661310661500
Std. dev1288.631507.531244.25876.08772.79865.64806.70925.22
Gap8.079.0610.0810.511.011.041.051.05

SDKP9Best679360672620664590661320733260732790732800732910
AVE676278.0668958.7661978.0659159.0731433.3731057.0731107.0730950.3
Worst671400667010659530657170730050729290728590728990
Std. dev1620.021566.351313.951201.62645.22869.96892.301024.07
Gap8.509.4910.4410.821.041.091.081.11

SDKP10Best691200681980677280672420758000757900758090758110
AVE687130.3679407.7672908.3669316.7756100.0756291.0756452.3756337.3
Worst684090676750669860667010754400754250754150753730
Std. dev1737.151527.541694.791452.26837.73993.511023.711038.86
Gap10.2211.2312.0712.541.201.181.161.17