ALGORITHMS

THE ECONOMIST

((2007) 9/15

85/ Most everyday, algorithms make numerous decisions about you and where you are going. It is like a step-by- step method of doing a job. Unfortunately, when these math transactions

occur they do so in a matter of seconds. To help you and to get to your account may take

hundreds of thousands sorts of various numbers. It is looking for you and thus picking you out of

many, many other people. In other words, a task can be executed in blinding speed with incredibly vast data.

Lets take the internet, people gravitate to the search engine that gets the most accurate information on a specific subject in the fastest time. At the moment, search engines work at unbelievable

speed, but may give you thousands of searches. You then have to wade through the

various options. Google provides the first option with the one that has the most

hits. That means most people go to that entry first. HOWEVER, search engines

are trying to get their algorithms to get to the best and fastest search that gives you the most information.

If you look up ELVIS PRESLEY////20TH ANNIVERSARY/// REUNION/// IN

MEMPHIS. Here is the problem. You first get lots of ELVIS PRESLEY.

Then you get the search for ELVIS. Then PRESLEY. Then 20th pops up. It can take you a long time to get the information about the 20th anniversary in Memphis and the reunion that was held.

Hopefully, the search will be shorten with algorithms that can handle millions of

bits of data. However we are not there yet.

Lets look at a simple algorithm by KUHN of IBM. In this one, we will assume that you have an old time charge card for one store. However, the store is one of many stores in

the retail chain. This algorithm will validate that your charge card is still viable. (You can be using some one else's that you just stol ed and it can invalidate the card if you are "out of pattern.") However that is another story.

THE FIRST SET OF NUMBERS indicates to the store your identity and your account number.

SO lets use

1  2  3  4  5

Now, that starts things going. THE SECOND SET OF NUMBERS is your number, but it has been reversed. So,

5   4  3  2  1.

This is number is a way to scramble and yet get to your account. Next, YOU TAKE

THE SECOND SET OF NUMBERS AND DOUBLE  EVERY OTHER NUMBER.

SO, skip 5 and go to 4 and then skip 3 and go to 2 and skip 1. So 4 plus 4 is

8, 2 plus 2 is 4,

So, we have 8 ( from the 4 that was doubled) and we have 4 (from the 2 that was doubled.)

8 plus 4 is equal to 12. Then we take 12 and divide by 10. That is 1.2/

1.2 is not a whole number, but a number with a fraction. That tells us that your card is no longer

valid. Go call the manager.

NOW LETS DO THE FORMULA with just the numbers.

1  2  3  4   5

5  4  3  2  1

8     4

12

12  divided by 10 equals 1.2

IT IS NOT A WHOLE NUMBER, SO IT IS INVALID.

Other algorithms are much more complex and we will leave you with the following.

WHAT IS AN ALGORITHM? IT IS A STEP BY STEP METHOD

FOR DOING A JOB IN THE FASTEST MOST ACCURATE WAY.

Folks, we have just started and that is where THE ECONOMIST ends. Can I take you any further? NOPE.

GOOD LUCK!!