Shannon vs Hartley Entropy

I left the flowchart from Lab 10 in the excel file so I hope that is a sufficient to posted it on my blog. The difference between Shannon and Hartley entropy is that Shannon includes probabilities into this entropy calculation and Hartley does not. Hartley just uses the log of the total amount of whatever he is calculating, in this case there were 21 grades, and uses a base 2. Hartley's entropy calculation seems to be a much greater number compared to Shannon's entropy.

Things I learned from Lab 9

In terms of excel functions and tools this lab was a nice refresher course. I've taken several classes that completely focus on excel and using this amazing program to make models and form predictions about those models. I'm currently a peer tutor for X201 Business Technology which is entirely devoted to excel so most of what we went over I had already knew of. Excel can really do some remarkable things that would be very time consuming and tedious is it were non-existent. Using graphs and scatter plots to help represent your data is so helpful because it gives you a new perspective of how the information is changing. Also the option of auto-filling and being able to pull down formulas make excel and extremely efficient tool for modeling. These graphs and regressions are great for showing correlations between data and that's exactly what we used them for in this situation. I've made quite a few business models so again, I've had some previous practice with creating models in excel and making conclusions on them. I'm glad we got into excel in this class because I really enjoy using the program making models.

Cars Traveled Per Mile

A B Output 1 Output 2

0 0 1 1
0 1 1 1
1 0 1 1
1 1 0 0

Conclusion: This simulation is essentially doing the same thing by testing certain positions and thier effect on the outcome. DeMorgans law is true. The only time there was two zeros or falses in the outputs was when both A and B were "1" or true.

A B Output

0 0 1

0 1 0

1 0 0

1 1 1

Conculsion: the circuit yeilds a positive result, "1", when both A and B are 0 and when both A and B are 1. The circuit tells us what the outcome is when certian switches get turned on and off.

In order to convert 110010101 into decimal I matched up each number starting with the first 1 on the farthest right with 2^0 then you move over to the left one number at a time and increase the power that 2 is raised to. For example, the last 1 on the right of that binary number is equal to 2^0 and the 0 that is to the left of that 1 is equal to 2^1. Then the 3rd number in from the right which is a 1, is equal to 2^2. The final conversion equaled 393. However the process of converting decimal to binary is a little different. You start by dividing the decimal by 2 and if there is no remainder then you write down a 0 for the binary. However, if there is a remainder then you write a 1 for the binary. As you start compiling the binary numbers you always tack on the most recent number on the left of the existing string. If there is a remainder and you've accounted for it by putting a 1 in the binary number, you leave the remainder off of the next calculation when you divide by 2. You continue this process of dividing the decimal by 2 until the quotient is 0. This final result of this decimal to binary conversion was 1000010001. The difference between a positional and non-positional number system is that a positional system has specific place values. It the kind of system we use in out society today. For example, the lowest place value is the rightmost position, and each position to the left has a higher place value. A non-positional number system, for example, may use groups of two kinds of wedges representing ones and tens.

Ch. 6 Global Swarming

As I began to read this article, I wasnt exactly sure where it was going with the whole snail analogy. It seemed quite ambiguous to be specifically describing how a snail makes its mucus to move around and form trails. But as Andy Clark's article progressed I realized the slug was refering to the a bigger meaning. Since we live in a time where there is more information than ever before, arranging it into a meaningful way has become the most difficult task at hand. And with all the technological advancments of our time, vitually everything we do can potentially be tracked and monitored. Whether it be phone calls, car movements through GPS, television channels, or snail tracks people want to record whats happening in our world to learn from certain experiences. Andy Clark brings up websites such as Amazon.com and Ebay.com who can track what people buy to customize and tailor thier websites to fit specific peoples needs. Its essentially business marketing research to help thier companies learn patterns in thier customers. I find this concept to be very intersting, in fact, its quite like some of the things I am studying in other classes right now. By recording what customers buy each time they visit these websites, the businesses can create profiles that can identify what these customers are most likely to buy. Through this data, companies can advetise certain products that customers are more likely to buy togther. For example, I recently learned that when middle aged males buy diapers they are highly likey to also buy beer. Because customer data showed this correlation, grocery stores placed beer and diapers closer together so that it is more likely that if a middle age male with a family goes to buy diapers he will also purchase beer. Marketing data drives lots of business decision and Its amazing how much it spills over into informatics. After completing the reading I understood why the artcile started off wih the snail reference. Humans leave trails and similarly follow the same patterns, much like that of the slugs. In a way this worries me because whos to say the trails some people are making is the right one to follow. Sometimes it seems like we are loosing are freedom in a sense that everything is tracked but at the same time other people make more educated decisions. I enjoyed this read and look forward to more of Andy Clarks thoughts.

Unix Commands

The four Unix commands that I learned today are "rm", "clear", "cal", and "date". In terms of thier equivilaent counterparts in Windows/DOS, the "rm" command would just be right clicking and deleting the file you want to remove. The "clear" command would be equal to clicking the "X" button on a window or the Minimize option to clear the screen. To find the calendar in windows all you have to do is double click the time in the very bottom right on the screen, this would be the same as the "cal" commands in Unix. And last but not least, the "date" command in Unix is accessed just about the same way as the calendar in Windows. The time is usually automatically viewable in the very bottom left of the screen and the date is accessable by double clicking on the time.

Modeling the World

Modeling the World was an exciting section of the lecture notes. I found the parts about how scientists model nature to be very interesting. It truly amazes me how people can think of ways to explain nature through equations and computer simulations such as biods and L-systems. The concept of Fibonacci sequences also intrigues me because of how it naturally occurs in the world.