Why Ants are Hard

نویسنده

  • W. B. Langdon
چکیده

The problem of programming an artificial ant to follow the Santa Fe trail is used as an example program search space. Previously reported genetic programming, simulated annealing and hill climbing performance is shown not to be much better than random search on the Ant problem. Enumeration of a small fraction of the total search space and random sampling characterise it as rugged with multiple plateaus split by deep valleys and many local and global optima. This suggests it is difficult for hill climbing algorithms. Analysis of the program search space in terms of fixed length schema suggests it is highly deceptive and that for the simplest solutions large building blocks must be assembled before they have above average fitness. In some cases we show solutions cannot be assembled using a fixed representation from small building blocks of above average fitness. This suggest the Ant problem is difficult for Genetic Algorithms. Random sampling of the program search space suggests on average the density of global optima changes only slowly with program size but the density of neutral networks linking points of the same fitness grows approximately linearly with program length. This is part of the cause of bloat.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Ergonomics of load transport in the seed harvesting ant Messor barbarus: morphology influences transportation method and efficiency.

We studied in the field the load transport behavior of workers of the polymorphic Mediterranean seed harvester ant Messor barbarus Individual ants used two different methods to transport food items: carrying and dragging. The probability of dragging instead of carrying varied significantly with both the mass of the item transported and its linear dimension. Moreover, the values of item mass and...

متن کامل

Survey of Finding Solution for optimization problem using Ant Colony Optimization

Ant Colony Optimization is one of the metaheuristic algorithms and first member of ACO is Ant System (AS). AS uses a population of co-operating ants also known as agents. The cooperation phenomenon among the ants is called foraging and recruiting behavior. This describes how ants explore the world in search of food sources, then find their way back to the nest and indicate the food source to th...

متن کامل

Signals Can Trump Rewards in Attracting Seed-Dispersing Ants

Both rewards and signals are important in mutualisms. In myrmecochory, or seed dispersal by ants, the benefits to plants are relatively well studied, but less is known about why ants pick up and move seeds. We examined seed dispersal by the ant Aphaenogaster rudis of four co-occurring species of plants, and tested whether morphology, chemical signaling, or the nutritional quality of fatty seed ...

متن کامل

Algorithmic Number Theory, 7th International Symposium, ANTS-VII, Berlin, Germany, July 23-28, 2006, Proceedings

Introducing a new hobby for other people may inspire them to join with you. Reading, as one of mutual hobby, is considered as the very easy hobby to do. But, many people are not interested in this hobby. Why? Boring is the reason of why. However, this feel actually can deal with the book and time of you reading. Yeah, one that we will refer to break the boredom in reading is choosing algorithmi...

متن کامل

Synanthropic Ants as Vectors of Pathogens in Hospitals of Iran

Background: Synanthropic ants can transmit pathogens especially in hospital environments,  but this fact had not been confirmed in Palaearctic region. This is the first study on confirming this ability of ants in this region. Methods: Three hospitals of Bandar Abbas, Iran have been selected for monthly sampling of ants in their various wards. The main processe...

متن کامل

Idle Ants Have a Role

We model and analyze the distributed task allocation problem, which is solved by ant colonies on a daily basis. Ant colonies employ task allocation in which ants are moved from one task to the other in order to meet changing demands introduced by the environment, such as excess or shortage of food, dirtier or cleaner nest, etc. The different tasks are: nursing (overseeing the hatching of newbie...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 1998