Learning Edcorner - Artificial Intelligence - Logic & Algorithms for problem solving Volume 2

AI or Artificial intelligence has many definitions associated with it. Read a new book and get a new definition. The AI, in simplest terms, is a way of solving difficult problems. The meaning of difficult problem is not which is difficult because of the logical requirements, but difficult because of the design of the computer itself. For example it is very easy for my four year old daughter to see a few samples of cars and then classify a vehicle as a car but can a normal computer program do that? Many of us have observed that when we meet a friend after years and find him grown in all dimensions, we are still in a position to recognize him. Researchers are working on programs which can recognize simple photos and take decisions based on the same. As long as the face is similar to the face the have seen to a large extent, they do not have any issues. The problem starts when there is a significant difference between two photos of a same person may be taken at different age or under different backgrounds. The researchers are finding difficulties in writing such programs due to obvious reasons as there is no algorithm known for solving these problems. My definition of difficult programs is these programs which are hard due to the design of the computer systems themselves. Humans can solve those problems as their minds are better equipped at solving such problems.

Here are some more examples. When a doctor can examine and diagnose a disease in few minutes why a robot (or a computer program) is not yet designed to do that? When an averagely intelligent person can learn to play games like table tennis, why a robot is not yet designed to do so? If I tell you that I went to the movie last night and I liked actors performance, will you conclude also that I went to a theater, I bought tickets, took my seat, spend my time viewing the movie and return back? In fact you may also additionally conclude that I am a fan of Shahrukh and may be a movie is XYZ as

it is just released. What do you think if a computer program is told to listen to my statement and reason from it?

Why it is hard for computers to solve these problems? Let me repeat that the computers are not designed to solve such problems. Humans have analog inputs, have a processor (the brain) which is very slow but runs highly parallel algorithms to solve problems (10 neurons with on an average 1000 connections to other neurons, total 10 connections) which are typically vision related, audio related and requires highly parallel processing. They possess common sense (somebody said that common sense is highly uncommon but is still possible for most to reason as I mentioned earlier in the text about the movie), they can work with incomplete information (I did not mention the name of the movie or the theater). They can also work with unstructured information (how have I recognized my friend after a long duration? I do not really know that myself!) Human brain stores information in a way that it is easier to have association and access information using that association. For example if I ask you the name of an actor who is tall, aged over 70 and with spectacles, all most all of you will immediately respond that I am talking about Amitabh Bachhan. If I ask my daughter a KG question, name a TV serial with a cat like alien being a friend of a human boy, she may immediately recall him to be Doremon. A guest may play few bars of music of a popular song and you may immediately recall it to be Awara Hun or Indiawale. All these are examples of how we use association in retrieving information. Our brain stores information in a form that it is easier for us to retrieve information in this fashion. Conventional databases, renowned for their ability to crunch data, are not good at accessing data using associations.

The AI or Artificial Intelligence is to write computer programs which can mimic human brain problem solving capabilities. Elaine Rich, in her book Artificial Intelligence puts it as AI is the study of programs at which, at the moment, people are better. One more author puts it as AI is about writing intelligent programs. One more definition is AI is about building entities which can understand, perceive, predict and manipulates like humans do. The last definition is little more interesting as it is also talking about entities which can act like humans and not merely programs. The robots which are confined in science fictions till now, AI is a study of methods of bringing them to real world. So far, we know, it is not really possible. You may also wonder why that is so. In fact, to solve any problem, we first of all must know what the real problem is. Let us try to understand this point little further. Let us again jump back to the definitions of AI. I used word difficult programs while somebody else used word intelligent programs. Do you consider brushing the teeth or picking up a chalk stick is an intelligent task? Unless you want your robot to do so, these tasks do not seem to require the use of intelligence. In fact when you start building your robot, you may have to decide the exact pressure to apply to pick up the tooth brush or a chock stick, a slight miscalculation results into breaking it. The brushing process also is required to decide the direction and pressure of the movement of the tooth brush, which, however trivial it look like, an extremely hard problem to solve even when the human head is considered stationary. Thus, I stick to the word difficult programs and not intelligent programs.

One may conclude learning from the functioning of brain and many intelligent people failing in designing a machine which can mimics simplest of functions of brain that the human brain is really a great invention and only the God can construct that!

To make the long story short, AI is about solving problems which are difficult to solve by conventional methods of computing as those methods are not designed to act like human brain. It is clear from above discussion that if we ever want the computer programs or Robots (with computer programs running within) to be successful in performing tasks that we have discussed so far, we need to design our computer systems or programs differently. AI is the study of designing computer systems and programs where they can perform more like humans and solve similar problems.

AI is not new discipline. In fact it begun in 60s when many researchers begun to take interest in learning how human brain functions and try predicting the human behavior from their perceived model of brain and try mimicking human behavior using automated programs. Many models ae presented till now and many research papers have given many researchers their Ph Ds and many people like me earned their living by teaching AI as a subject. The ultimate objective of building a human like machine is not yet been met. It is not likely to be met in foreseeable future as well.

Does that mean that we should not study AI? Or AI is a dead discipline? No. Let us understand why. Though study of AI so far could not exactly achieve the goal it started with (and still perceives to achieve), it has contributed revolutionary solutions in the field of computer science. For example we have programs which can find traffic related parameters from visual images and provide intelligent traffic control. There are programs which can recognize peoples faces to certain extent and provide search options like Give me all photographs where this face appears in. Signature recognizing programs are common. Solutions which look at PDF files and convert them to document files by classifying each character of the PDF image are available. Access control systems which use biometric measures like thumb impression, retina scanning or face recognition for authentication are already available. Expert systems which may not be able to exactly work like a doctor but an assistant are available. Thus, AI has achieved many things. Game playing programs are in huge demand today. Most, if not all, use one or the other form of AI.