Greetings from San Diego - Calculator Poll Question (Back to School)

Greetings from San Diego, am on vacation until Labor Day. Specially I am at a Starbucks stop on my way to Encinitas Beach, enjoying a Chai Blended Latte.

I just came from the Giesel Library at the University of California, San Diego. It took me forever to find it; along with the correct parking lot. The library is named after Theodore Seuss Giesel, better known as Dr. Seuss. Naturally, I managed to buy a Dr. Seuss book - my cousin's daughter is going to enjoy it, I'm sure.

Updates

There is going to be Part 8 of the Differential Equation series, maybe more. I found an interesting way, maybe easier than Laplace Transforms or eigenvalues (the former I covered) to solve systems of differential equations. I am also aiming to do a blog on the Runge Kutta algorithm.

Back To School...For a Lot of Us

School is either right around the corner or even here for a lot of students. Got to ask the math students: what calculator (or calculators) are you using? (And why?). Even if you are not a student, feel free to answer in the comments


Well, it's on to the beach for sunshine and sunset, and probably dinner. Have a great day everyone!


Eddie

This blog is property of Edward Shore. 2013

Friday Potluck (color calculators, orbits, baseball)

Today is going to be a hodgepodge of what's been happening over the last week. (when I am not at work, working out, sleeping, etc)

Congratulations to my cousin Gina, she gave birth to a beautiful girl, Beth on June 28! :)

The Calculator Rainbow is Back

During the last two weeks, I saw that Staples, Office Depot, and Target is getting ready for Back to School. it must be around the corner, man, we are already in July 2012! Texas Instruments has once again leashed its colorful band of TI-30x iis calcualtors in many colors: light blue, green, orange, and pink. There is also a pink version of the multi-line TI-30 XS in addition to its normal pale blue sibling. Yeah, it is hard to admit to that as a guy, I own anything pink (I called it light red at first). Even Casio gets in the act, at least at Staples, the fx-300ES PLUS has black, pink, and I think green.

I could not resist.

Orbits and Kepler's Laws

A good source to learn, brush up, and/or be entertained is the videos of bestdamntutoring. Saul Hernandez, of bestdamntutoring.com, is awesome in how he explains concepts, he speaks clearly and gets to the point.

Link to bestdamntutoring's YouTube page.

Now you know where I brushed up on Kepler's Laws, in part to hopefully prepare myself for the astronomy meeting tomorrow night (where I am meeting with my good friend Mike Grigsby):

1. Planets travel in an elliptical orbit with the sun at on of the two foci of the ellipse.

Note: The foci are located a*e units away from the center of the ellipse along the semi-major axis line. The variable a represents the length of the semi-major axis and e represents the eccentricity of the ellipse.

2. Planets sweep out at equal areas at equal times. This explains why planets move faster when they are closer to its sun and move slower when planted are away from the sun.

3. The period of an orbit can be described by the following equation:

T^2 = (4 π^2 a^3) / (G M) where

T = period of the orbit
a = length of the semi-major axis. Often, a circular orbit is used instead and hence the radius is substituted for a.
M = Mass of the central object. An assumption is made that the mass of the central object is much larger than the mass of the object being orbited.
G = Gravitational Constant. In space,
G = 6.67428 x 10^-11 m^3/(kg s) =
1.069117097 x 10^-9 ft^3/(lb s).

(Thank you TI-36X Pro. )

Baseball and WAR

In attempt to get a further understanding of Sabermetrics, the analysis of baseball and softball. We all know that part of the game of baseball includes stats galore, and at least in the United States, shaving cream pies and Gatorade baths to game day heroes. I wish there was a golly stat for pies, that would be awesome... OK I am getting off topic.

I took a look the ever vaunted stat, the WAR, or Wins Above Replacement. Basically, if a player's WAR is high, at least a 4, he is doing well. WAR is defined as a measurement of a player's "value" over a scrub (low-level minor-league) player. The goal of WAR is to assign one major value to every player that takes into account everything possible.

Thankfully, sites like www.fangraphs.com has a WAR score for just about everyone who has played baseball (at least in the US).

There are two types of WAR, one for the batters and one for the pitchers.

Generally, the batter's WAR consists of a weight batting average weighed against a dynamic league average, UBR (baser inning measure which is not a rigid formula but made of a lot of judgement calls, whose I don't know), and UZR (fielding rating calculated of the type of play and difficulty factor). None of the formula is straight forward, and as I if understand it, the weights change over time.

I didn't get much into how a pitcher's WAR is calculated, but I imagine it is complex as a batter's WAR.

First of all, where do these analysts get the time to manage the massive amount of calculations? Do they ever enjoy the game? Second, how are the weights determined? So far I have not seen anything on how the weights are calculated - are they determined by complex formulas or arbitrarily?

A Word of Thanks

Thank you to everyone who reads my comments and leave comments. I am very pleased to read that many people are enjoying this blog. This blog is one of favorite things to do. I appreciate the compliments and comments.

Enjoy the day,
Eddie


This blog is property of Edward Shore. © 2012