Title: Robert J. Marks II
1Does Evolution Require External Information? Some
Lessons From Computational Intelligence??????????
--?????????
- Robert J. Marks II
- Distinguished Professor Of Electrical and
Computer Engineering
2Abstract??
- Engineers use models of science to improve
quality of life. Computational intelligence is
such a useful engineering tool. It can create
unexpected, insightful and clever results.
Consequently, an image is often painted of
computational intelligence as a free source of
information. Although fast computers performing
search do add information to a design, the needed
information to solve even moderately sized
problems is beyond the computational ability of
the closed universe. Assumptions concerning the
solution must be included. For targeted search,
the requirement for added information is well
known. The need has been popularized in the
last decade by the No Free Lunch theorems. Using
classic information theory, we show the added
information for searches can, indeed, be
measured. The total information available prior
to search is determined by application of
Bernoulli's principle of insufficient reason. The
added information measures the information
provided by the evolutionary program towards
achieving the available information. Some
recently proposed evolutionary models are shown,
surprisingly, to offer negative added information
to the design process and therefore perform worse
than random sampling.
3What is Evolutionary Computation?????????
- Simulation of Darwinian Evolution on a Computer
How good is each solution?
A set of possible solutions
Computer Model
Survival of the fittest
Next generation
Mutation
Keep a set of the best solutions
Duplicate, Mutate Crossover
4Search in Engineering Design???????
- Can we do better? Engineers
- Create a parameterized model
- Establish a measure designs fitness
- Search the N-D parameter space
5Random Search You are told Yes No (Success
and no success)????????????
Target
6Directed Search Information is given to
you????????????
- e.g.
- Warmer!
- Steepest Descent
- Conjugate Gradient Descent
- Interval Halving
Target
7Blind Searches... ????
- Monkeys at a typewriter
- ??????
27 keys Apply Bernoulli's principle of
insufficient reason in the absence of any prior
knowledge, we must assume that the events have
equal probability Jakob Bernoulli, Ars
Conjectandi'' (The Art of Conjecturing), (1713).
Information Theoretic Equivalent Maximum
Entropy (A Good Optimization Assumption)
8Random Searches... ????...
- IT WAS A DARK AND STORMY NIGHT
- ??????????
2730 8.73 x 1042 1 (143 bits) The same odds
as choosing a single atom from over twenty
trillion short tons of iron.
Using Avogadro's number, we compute 2730 atoms
times 1 mole per 6.022 1023 atoms times 55.845
grams per mole times 1 short ton per 907,185
grams 1.22 x 1012 short tons.
9Converting Mass to Computing Power????????
- Minimum energy for an irreversible bit (Von
Neumann-Landaurer limit - ln(2) k T 1.15 x 10 -23 joules
- Mass of Universe 1053 kg. Convert all the mass
in the universe to energy (Emc2) , we could
generate1 7.83 x 1092 Bits - Assume age of universe is 13.7 billion years.
- Making the universe conversion to energy every
nanosecond since the big bang gives only
3.4 x 10119 Bits
1. Assuming background radiation of 2.76 degrees
Kelvin
10Random Searches... ????...
- A Definition of Impossible
- ????????
Convert all the mass in the universe to energy a
billion times per second since the big bang
10120 bits
120
10
? Impossible
11How Long a Phrase? ????????
Target
- IN THE BEGINNING ... EARTH
- JFD SDKA ASS SA ... KSLLS
- KASFSDA SASSF A ... JDASF
- J ASDFASD ASDFD ... ASFDG
- JASKLF SADFAS D ... ASSDF
- .
- .
- .
- IN THE BEGINNING ... EARTH
Expected number NL
12How Long a Phrase from the Universe?
?????????????
Number of bits expected for a random search
- pN-L
- 10120 bits NL log2 NL
For N 27, pN-L L 82 characters
13Prescriptive Information in Targeted
Search???????????
14Fitness ???
Each point in the parameter space has a fitness.
The problem of the search is finding a good
enough fitness.
15Search Algorithms????
Steepest Ascent Exhaustive Newton-Rapheson
Levenberg-Marquardt Tabu Search Simulated
Annealing Particle Swarm Search Evolutionary
Approaches
Problem In order to work better than average,
each algorithm implicitly assumes something about
the search space and/or location of the target.
16No Free Lunch Theorem???????
- With no knowledge of where the target is at and
no knowledge about the fitness surface, one
search performs, on average, as good as any
another.
17No Free Lunch Theorem Made EZ????????????
Find the value of x that maximimizes the fitness,
y.
y
x
Nothing is known about the fitness, y.
18Quotes on the need for added information for
targeted search ???????????????
- unless you can make prior assumptions about the
... problems you are working on, then no search
strategy, no matter how sophisticated, can be
expected to perform better than any other Yu-Chi
Ho and D.L. Pepyne, (2001). - No free lunch theorems indicate the importance
of incorporating problem-specific knowledge into
the behavior of the optimization or search
algorithm. David Wolpert William G. Macready
(1997).
- Simple explanantion of the No Free Lunch
Theorem", Proceedings of the 40th IEEE Conference
on Decision and Control, Orlando, Florida, - "No free lunch theorems for optimization", IEEE
Trans. Evolutionary Computation 1(1) 67-82
(1997).
19Therefore...??
- Nothing works better, on the average, than random
search. - For a search algorithm like evolutionary search
to work, we require prescribed exogenous
information.
20Evolutionary Search...????
- Evolutionary search is able to adapt solutions
to new problems and do not rely on explicit human
knowledge. David Fogel
BUT, the dominoes of an evolutionary program must
be set up before the are knocked down. Recent
results (NFL) dictate there must be implicitly
added information in the crafting of an evolution
program.
(emphasis added D. Fogel, Review of
Computational Intelligence Imitating Life,
IEEE Trans. on Neural Networks, vol. 6,
pp.1562-1565, 1995.
21Evolutionary Computing????
- e.g. setting up a search requires formulation
of a fitness function or a penalty function.
Michael Healy, an early pioneer in applied search
algorithms, called himself a penalty function
artist.
22Can a computer program generate more information
than it is given
?
- If a search algorithm does not obey the NFL
theorem, it is like a perpetual motion machine -
conservation of generalization performance
precludes it. Cullen Schaffer (1994)
anticipating the NFLT.
- Cullen Schaffer, 1994. A conservation law for
generalization performance,in Proc. Eleventh
International Conference on Machine Learning, H.
Willian and W. Cohen, San Francisco Morgan
Kaufmann, pp.295-265.
23Shannon Information Axioms??????
- Small probability events should have more
information than large probabilities. - the nice person (common words ? lower info)
- philanthropist (less used ? more information)
- Information from two disjoint events should add
- engineer ? Information I1
- stuttering ? Information I2
- stuttering engineer ? Information I1 I2
24Shannon Information????
I
p
25Targeted Search????
Bernoulli's Principle of Insufficient Reason
Maximum Entropy Assumption
26Available Information??????
?
This is all of the information we can get from
the search. We can get no more.
27Available Information Interval
Halving???????????
no 0
This is a perfect search
no 0
yes 1
yes 1
4 bits of information 0011
28Search Probability of Success.Choose a search
algorithm...????????. ????????
Let
be the probability of success of an evolutionary
search.
From NFL, on the average, if there is no added
information
If
information has been added (or were lucky).
29Added Information Definition???????
Checks
- For a perfect search,
all of the available information
30Added Information????
Checks
2. For a blind query,
no added information
31Added Information ????
?
Prescriptive information can be NEGATIVE
32EXAMPLES of PRESCRIPTIVE INFORMATION????????
Interval HalvingRandom SearchPartitioned
SearchFOO Search in Alphabet
NucleotidesNegative Added Information
33Prescribed Exogenous Information in Random
Searches...????????????
For random search, for very small p
Q Number of Queries (Trials) p success of a
trial pS chance of one or more successes
34Prescribed exogenous Information in Random
Searches...????????????
- Added information is not a function of the size
of the space or the probability of success but
only the number of queries. - There is a diminishing return. Two queries gives
one bit of added information. Four queries gives
two bits. Sixteen queries gives four bits, 256
gives 8 bits, etc.
352. Prescribed exogenous Information in
Partitioned Search...?????????????
yada yada yada
362. Prescribed exogenous Information in
Partitioned Search... ?????????????
For random search
For Partitioned Search
Hints amplify the added information by a factor
of L.
372. Prescribed exogenous Information in
Partitioned Search...?????????????
For perfect search using partitioning
information, set
Iterations From Information
Since L28, if we set
it follows that...
L 27 characters, 26 in alphabet
382. Prescribed exogenous Information in
Partitioned Search...?????????????
- Comparison
- METHINKSITISLIKEAWEASEL
Reality For Partitioned Search
For Random Search
There is a lot of added information!
L 28 characters, 27 in alphabet
39 Single Agent Mutation (MacKay) ???????
2. Single Agent Mutation (MacKay)
- Specify a target of bits of length L
- Initiate a string of random bits.
- Form two children with mutation (bit flip)
probability of ?. - Find the best fit of the two children. Kill the
parent and weak child. If there is a tie between
the kids, flip a coin. - Go to Step 3 and repeat.
- (WLOG, assume target is all ones)
402. Single Agent Mutation (MacKay)???????
412. Single Agent Mutation (MacKay)
Single Agent Mutation (MacKay) ???????
- If ? ltlt 1 , this is a Markov birth process.
42? 0.00005, L128 bits
433. Prescribed exogenous FOO Information?????????
??
- FOO frequency of occurrence
E 11.1607 M 3.0129
A 8.4966 H 3.0034
R 7.5809 G 2.4705
I 7.5448 B 2.0720
O 7.1635 F 1.8121
T 6.9509 Y 1.7779
N 6.6544 W 1.2899
S 5.7351 K 1.1016
L 5.4893 V 1.0074
C 4.5388 X 0.2902
U 3.6308 Z 0.2722
D 3.3844 J 0.1965
P 3.1671 Q 0.1962
Concise Oxford Dictionary (9th edition, 1995)
Information of nth Letter
Average informationEntropy
44English Alphabet Entropy?????
- English
- Uniform
- FOO
- Added information
45Asymptotic Equapartition Theorem??????
?
- A FOO structuring of a long message restricts
search to a subspace uniform in ?.
Target
T
- For a message with L characters with alphabet of
N letters...
FOO Subspace
46Asymptotic Equapartition Theorem??????
- For King James Bible using FOO, the prescriptive
information is - I 6.169 MB.
- Available Information
- I? 16.717 MB
- Can we add MORE information?
- digraphs
- trigraphs
474. Example of Negative Prescriptive Information
??????????
- The NFL theorem has been useful to address the
"sometimes outrageous claims that had been made
of specific optimization algorithms - S. Christensen and F. Oppacher, "What can we
learn from No Free Lunch? A First Attempt to
Characterize the Concept of a Searchable,
Proceedings of the Genetic and Evolutionary
Computation (2001).
484. Example of Negative Prescriptive Information
??????????
49Schneiders EV???????
50Equivalent to inverting a perceptron
51Where is the source of exogenous
information??????????
The universe is not old enough nor big enough to
allow the evolution of complex life.
- There must be exogenous information being
prescribed in some way guide this process. - Where does it come from? Or is there something we
are not considering?
52First Possibility 1. The Wrong Problem
Nonteleological Evolution???????????
- Pure Darwinism claims evolution does not have a
target and is therefore nonteleological. - This simply displaces the problem to an
information rich environment wherein evolution
can thrive. From where do we get the information
for this information rich environment?
53Second PossibilityParallel Universes More
Matter???????????(????)
- Parallel Universes
- (Quantum) The big bang was a wave function one of
whos states was our universe. There exists
numerous others. - (String Theory) The big bang was the product of
the chance touching of multidimensional branes. - The universe of universes is now big enough to
explain life with no external information. - Problem These are pure conjecture and require a
faith in scientific materialism.
54Third PossibilityPanspermia More
Time????????(????)
- Panspermia is a theory supported by Sir
Francis Crick, Nobel Laureate for discovering DNA.
- Panspermia claims life was planted on earth by
aliens. Directed panspermia, supported by Crick,
says this was done on purpose. - Problem This is pure conjecture and requires a
faith in science fiction.
55Fourth PossibilityThe Universe was Created by
God???????????
- This is taught in the Bible of the Jew, Christian
and Muslim. From Genesis - In the beginning God created the heavens and
the earth. - Now the earth was formless and empty, darkness
was over the surface of the deep, and the Spirit
of God was hovering over the waters.
No Information
56Fourth PossibilityThe Universe was Created by
God???????????
- And God said, "Let there be light," ... "Let
the water under the sky be gathered to one place,
and let dry ground appear." "Let the land
produce vegetation." "Let the water teem with
living creatures, and let birds fly..." "Let the
land produce living creatures according to their
kinds..." ""Let us make man in our image, in
our likeness, and let them rule over the fish of
the sea and the birds of the air, over the
livestock, over all the earth, and over all the
creatures that move along the ground."
Information Structure
57Science and Theology?????
- My fellow astronomers are scaling the
mountains of ignorance, conquering the highest
peak, pulling themselves over the final rock
to be greeted by a band of theologians who
have been sitting there for centuries. -
Robert Jastrow, founder and director of NASA's
Goddard Institute for Space
58Summary of Points...????
- Targeted Evolutionary Computing ? Schaffers
Perpetual Motion Machine for Information - Prescribed information can be measured
analytically or through simulation. - Some models of simulated evolution have negative
prescriptive information. Random chance works
better. - Prescribed exogenous information should be
reported in all published models of simulated
targeted evolution. - What is the source of exogenous information?
59Finis
Finis
Finis
Finis
Finis
Finis