People ask me simple questions.. so overwhelmingly simple that i get all overwhelmed answering them..
Hence i've formulated the following for the ease of it all;
How to tell your Grand Mother what are Adaptive Filters?
Problem Statement: There are two pots of soup placed side by side. There are some spices that are added in one of the pots, the other one has none.
How is it possible to add exactly the same amount of spices?
Since this setup is imaginary enough, therefore it is assumed that the spices can be added or subtracted from the pot. It can be safely assumed that all spices contained within, can be quantified in terms of tea spoons and only integer number of tea spoons are allowed.
Solution: Here are the steps for one of the possible ways of doing it.
1. Add/subtract tea spoon(s) of spices,
2. Taste both soups,
3. Judge which spices are missing, or which are extra, then goto step 1.
These three steps are exactly followed in an Adaptive Filter algorithm.
Lets get into a bit of a detail here;
We can fix the number of tea spoons that can be added or subtracted. To wit; always 5 tea spoons would be added/subtracted. In Adaptive filter theory, we like to call this specific number; step_size. This might help to reach the desired number of spices very quickly, but it might also lead to disaster, that is to say; we might never be able to find the correct number of spices if it is not multiple of 5. In that case we'd say that we couldn't converge, and at the end of the day, the soup would taste awful.
So, to be on safest side, the smallest possible step size should be chosen.
[Never mind if it takes more time]
Returning -
Tasting both soups gives us the difference in spices contained in them, or as we say in Adaptive Filtering terms; the error between the desired soup spices and our guess of spices.
So, our brain uses this error to make a rough guess about the amount of spices to be added in next step.
In Adaptive filters a formula acts as the "brain", thus providing us with the amount of spices to be added in next step.
How to tell your mother what are algorithms?
Compare it to a recipe.. An algorithm is made up of instructions that determine how to proceed step by step in seeking the answer to a question (or preparing a mouth-watering meal for instance).
In the computer world the important thing is to tackle all problems in the most efficient way possible, to find the solution in the quickest possible way. That's where algorithms come into play.
Oh n one more thing, never fret if your cooking experiment fails altogether, since algorithms are based upon falsifiable hypotheses anyway :p
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