Index

Adaptive Representation through Learning, 33
ADF, 23-24, 33
as evolving primitive, 102-106, 110
as representation change, 207
bracket problem, 144
cache, 118
call by reference, 125
comparison with GLiB, 33
constraining use, 118, 141
dyck problem, 149
FUNC, 128, 129
in PADO, 164
list problem, 124-127
forwhile, 126
syntax restrictions, 129
pass by reference, 91
list problem, 124
queue problem, 107
primitives, used in, 85, 101
queue problem, 84, 90, 109
RPN problem, 154, 158
semantically constrained, 107
support in GP-QUICK, 268
treating rbp as ADF, 85, 90
ADM, see Automatically Defined Macros
ARG1
dyck problem, 150
list problem, 127, 128
south wales problem, 255
arg1
bracket problem, 145
dyck problem, 150
list problem, 127, 128
syntax restrictions, 129
queue problem, 84
syntax restrictions, 101
RPN problem, 156
stack problem, 66
essential in, 179
extinct, 179
fitness covariance, 175, 179
ARG2
list problem, 128
arg2
dyck problem, 150
RPN problem, 156
ARL, see Adaptive Representation through Learning
Automatically Defined Functions, see ADF
Automatically Defined Macros, 23
autonomous agents, 41, 47
playing soccer, 47
aux, 45, 128
list problem, 125, 127
initialised, 130
queue problem, 85-87, 93, 95, 99, 108
bug, 109
differences between experiments, 118
different from stack, 122
harder than stack, 120-121
initialised, 88
syntax restrictions, 101
use in shuffler, 94-95
stack problem, 66-68
deceptive, 180, 205
essential in, 179
extinct, 179
fitness covariance, 175
initialised, 69
use in solutions, 71, 180
auxiliary register, see aux

BioX, 39
bloat
inherent in variable length representations, 77-78
list problem, 131
mutation experiments, 34
RPN problem
removal, 160
stack problem, 76
boids, 41
boolean 6-multiplexer
code growth, 76-77, 191
effect of parsimony pressure, 30
branch typing, 23
in multi-tree crossover, 46
Bruce, 140, 163, 205
building block
disruption, 180
extinction, 180
building blocks, 15
introns, 119
queue shuffler, 95, 119

cache
ancestor's fitness, 269-270
bracket problem
ADF evaluation, 145
DAG, 27
future work, 212
loadflow, 266
network connectivity, 266
queue problem
ADF evaluation, 118
recommended, 211
tree evaluation, 270
calculator problem, see RPN problem
call by reference, see ADF, call by reference
case sensitive primitives names, 66
cellular automata, 50
clones, 184
crossover
binary tree model, 197-199
leaf measurements, 201
leaf model, 199-200
measurements, 196, 197
whole tree, 196-197
disable reproduction operator, 205
low variety, 195, 202
closure, 21
extended, 28
indexed memory addresses, 67
protected modulus, 84
co-evolution
42 trees, 259
queue problem, 82
references, 29, 49, 180, 208
representation, 207
stack problem, 65
ten operations, 123
test case, 205
contingencies
electrical network, 262-265
coroutine model, 32
CPU
complexity of problem, 64
usage
dyck problem, 153
list problem, 132
RPN problem, 159
CPU complexity of scheduling heuristics, 266
CPU limit, south wales problem, 260
CPU penalty
faster solutions
list problem, 135
RPN problem, 157, 160
increased after solution
dyck problem, 150, 152
list problem, 131
RPN problem, 155-157
list problem, 123, 127
pareto, 53, 131
removal of introns, 141
south wales problem, 256, 259, 262
crossover, 2
ADF, 23, 33
asymmetric, 53
between different implementations, 80
bit string, 14
bloat prevention, 120
building block assembly, 15
ADF, 33
clones, 184, 188
binary tree model, 197-199
leaf measurements, 201
leaf model, 199-200
measurements, 196, 197
run time reduction, 206
stack problem, 184-186, 192, 195
closure, 21
context preserving, 35
depth based, 34
directed, see directed crossover
disruption, 24, 180
diverse individuals
fitness niches, 129, 141
effect on reproduction rate, 52, 170
four node problem, 249
introns, 78
length restriction
stack problem, 70
measurements
stack problem, 200-202
multi-tree, 46-47
42 trees, 259
list problem, 124
queue problem, 84
RPN problem, 154
stack problem, 65
no code sharing between different tree types, 91, 172
offspring same fitness, 74
one offspring, 184
one point, 36
program length limit, 268
protected from by encapsulation, 33
random
Price's theorem, 170-171
run out of steam, 206
scheduling representations, 248-249
self
demes, 53
semantically constrained, 107
short fit programs, 78
solution rediscovery, 207
STGP, 28
successful
stack problem, 202-204
tree, 3
unique offspring, 206
variety, 189
constant model, 190-191
quadratic model, 191-195
stack problem, 195-197
whole trees reduces variety, 196-197
cultural transmission, 69

DAG
Storing population in, 27
data mining, 39
Dec_Aux
queue problem, 85-87, 93, 95, 99
different from stack, 122
harder than stack, 120-121
syntax restrictions, 101
stack problem, 66-68
deceptive, 180, 205
essential in, 179
extinct, 179
fitness covariance, 175, 179
use in solutions, 180
deception, 6, 21
co-evolution, 205
deme, 205
dyck problem
static program, 154
future work, 211
list problem, 141
mutation rate to escape, 205
niches, 141, 205
novel genetic operators, 207
queue problem, 121
RPN problem, 160
stack problem, 180, 205, 207
deme, 49-53
beneficial, 49
bracket problem, 145, 146
deceptive problems, 205
defocusing search, 207
diversity, 141, 211
dyck problem, 146, 150, 152
elitism, 56
genetic similarity, 55
queue problem, 103-104
references, 37
speed of convergence, 52
Directed Acyclic Graph, see DAG
directed crossover, 133
error location, 132
list problem, 127
software maintenance, 140
survey, 47-49
distributed artificial intelligence (DAI), 41
divide by zero, 21

Effort, 75, 237
elitism
demic populations, 56
list problem, 127
multi-objective fitness function, 57
required if random removal, 211
south wales problem, 256
steady state population, 56
end nodes, 20
error location guiding crossover, 132
error trapping not required
list problem, 130
queue problem, 81, 88
stack problem, 64, 69
error, memory address
abort
queue problem, 95
stack problem, 67
continuing on
queue problem, 86, 122
options, 67
error, recursion
abort
queue problem, 92
error, stack
continuing on, 145
external nodes, 20
extinction
critical stack primitives, 178
list primitives, 135

feature films, 41
Fisher's fundamental theorem, 177
fitness, 9, 21-22
avoid evaluation of clones, 206
avoiding excess resource consumption, 94
cache, see cache
deceptive, see deception
diversity, 183
dynamic, 29-30
evaluations required, see effort
future work
reduce test case, 102
identical from different programs, 183
manual, 41
multi-objective, see pareto
novelty reward, 259
offspring fitness correlation, 170
primitive covariance, see Price's theorem
program size, see parsimony
queue problem
harder than stack, 120
run time, 269
rank based, 44
redesign, 208
rediscovery, 202
reducing test case, 151
rescaling, 44
sharing, see niches
sufficient testing, 132
test case, 22
Flockton, 54
fluff, see introns
for
south wales problem, 256
syntax restriction, 254
forwhile, 126, 128
bracket problem, 145, 165
list problem, 127
CPU penalty, 131
CPU usage, 160
in ADF only, 126
iteration limit, 126
syntax restriction, 126
functions, 20

Gathercole, 29, 30, 32, 89
generation equivalent, 45
genetic drift, 55
Price's theorem, 170
genetic programming, origins, 17
Gordon, 248, 249
GP-QUICK, 267
support for ADFs, 23, 268

halting problem, 31

Inc_Aux
queue problem, 85-87, 93, 95, 99
different from stack, 122
harder than stack, 120-121
syntax restrictions, 101
stack problem, 66-68
deceptive, 180, 205
essential in, 179
extinct, 179
fitness covariance, 175
use in solutions, 180
indefinite loops, 31
indexed memory, 45
avoiding deception, 205
greedy solutions, 94
penalty, 94, 118, 131
increased after solution, 131
south wales problem, 253
survey, 160-164
information theory
queue problem, 121
size of test case, 210
stack problem, 80
initialisation
aux
bracket problem, 145
dyck problem, 151
queue problem, 88
RPN problem, 155
stack problem, 69
indexed memory
bracket problem, 145
dyck problem, 151
GEMS, 161
list problem, 130
queue problem, 88
references, 131
RPN problem, 155
south wales problem, 254
stack problem, 69
internal nodes, 20
introns, 48
avoiding fitness evaluation, 270
building blocks, 119
concealing convergence, 7
hiding building block, 103
inherent in variable length representations, 77-78
loss of variety, 183
removal by CPU penalty, 141
some references, 37
stack problem, 76
useful with mutation, 35
wetware, 144
iteration, see for, forwhile
constrained, 161
CPU usage, 22, 31-32
little research, 31, 43

Koza, 1-272

length, see program size
loop, see for, forwhile

machine code
RISC, 27, 161
Z80, 161
Maze
Solving with a stack, 63
MDL, 30-31
biasing search, 49
general programs, shorter, 210
MInc
implementation, 87
queue problem, 85, 87, 95, 99
harder than stack, 120-121
syntax restrictions, 101
minimum description length, see MDL
mod
implementation, 85
queue problem, 84
south wales problem, 256
models of loss of variety, 188
modulus, see mod
modulus increment, see MInc
multi-tree programs, 46-47
mutation, 2
artificial life, 41
background primitive frequency, 208
bit string, 13
defocusing search, 207
possible benefit, 141, 211
restore diversity, 205
south wales problem, 254
survey, 34-35

neutral crossovers, 74
NFL, see No Free Lunch
niches, 54-57
deception, 205
defocusing search, 207
diversity, 141, 211
dyck problem, 150
future work, 142, 211
genetic similarity, 55
list problem, 123, 129-130
RPN problem, 156
south wales problem, 259
No Free Lunch, 16

object oriented programming
Bruce, 163

PADO, 28, 164
anytime algorithm, 31
run time in fitness, 131
panmictic population, 49
fast convergence, 211
Parallel Distributed Genetic Programming, see PDGP
pareto, 53-57
avoiding loss of improvements, 102
CPU penalty, 53
dyck problem, 150, 152
future work, 211
list problem, 123, 129
memory penalty, 53
queue problem, 102
RPN problem, 155, 156
south wales problem, 259
parsimony, 30, 131
biasing search, 49
pass by reference, see ADF, pass by reference
PDGP, 28
permutation of trees, 35
permutation, GA chromosome, 248-250, 260, 266, 267
PGA, 250
PIPE, 36
point typing, 205
popcorn, indefinite loops, 31
prefix jump table, 70
efficient, 26
GP-QUICK, 268
premature convergence, 49
change representation, 207
demes, 103
niches, 152
offspring selection, 101
short test case, 130
Price's theorem, 168
genetic algorithms, 170
proof, 168
Probabilistic Incremental Program Evolution, see PIPE
program size, see bloat, MDL, parsimony
boolean 6-multiplexer, 76-77
CPU penalty
list problem, 135
limit, 89-90
bracket problem, 145
crossover, 46
dyck problem, 150
GP-QUICK, 268
list problem, 127, 133
loss of diversity, 89
Price's theorem, 170-171
queue problem, 93, 95, 99, 108
random individuals, 90
RPN problem, 156
south wales problem, 256
stack problem, 66, 70
list problem, 137
mutation rate, 254
part of diversity, 184
queue problem, 89, 117
random trees, 89
south wales problem, 259
stack problem, 76-77, 79
initial fall, 78
protected functions, 21
protected modulus, see mod
pUnRestrictWt, 47
effect in full binary trees, 197

random search, ineffective, 75
rank selection, 44
rankone, 266
Rational Allocation of Trials, 30
recursion
CPU usage, 22, 31-32
little research, 43
prevented
list problem, 125
queue problem, 91
references, 91
Red Queen, 180
rheological models, 39
Ross, 29, 30, 32, 89, 249, 250

scalar memory, see aux
scoping rules, 125
future work, 211
SDRS2, 266
search space
automatic program generation, 17
explore v.\ exploit, 205, 207
impact of primitives and fitness, 20
indexed memory, 210
multiple solutions, 80, 120
poorly behaved, 42
program length, 210
scheduling problem, 253, 260, 265-266
size, 266
stack problem
size, 16
STGP, 49
techniques, 15-16
seeding
references, 140
software maintenance, 139
south wales, 254
semantic constraints
queue problem, 107
Set_Aux, 128
list problem, 127
queue problem, 85-87, 93, 95, 99, 108
different from stack, 122
harder than stack, 120-121
syntax restrictions, 101
size of random trees, 77, 89
structured population, 49
sufficiency, 20
swap, 45
bracket problem, 145
definition, 166
list problem, 127
south wales problem, 256
swap, genetic operator, see permutation of trees
syntax restrictions
list problem, 126, 129
queue problem, 90

tableau, 68
terminals, 20
tournament selection, 44
steady state, 187
transmission function, 20
tree leafs, 20
tree size limit, 268
dyck problem, 150
list problem, 127, 133
RPN problem, 156
Turing complete, 27, 43

virtual reality, 41

wrapper, 68
bracket problem, 145
dyck problem, 150
queue problem, 88, 93, 95, 99, 108
empty, 122
RPN problem, 156
south wales problem, 256
stack problem, 66, 68
write_Aux
queue problem
different from stack, 122
not used, 86-87
stack problem, 66-68
deceptive, 180, 205
essential in, 179
extinct, 179
fitness covariance, 175
use in solutions, 180

Yang, 54



Bill LANGDON 2001-08-19