Wednesday, November 9, 2011

License Plate Rules

My home state of Maryland does not use the letters I, O, Q, and U on its standard issue passenger license plates. Presumably the I and O are not used to avoid confusion with the numbers 1 and 0, but I don't know why the Q and U are avoided. They do sound similar, but that is true of many of the letters that are used. Other states do not follow these rules. The data below shows which of these letters I have seen on non-vanity license plates from other states and gives some examples of plates using these letters. The standard format of the license plate is shown enclosed in parentheses where "d" stands for a digit (0-9) and L stands for a letter (A-Z). Examples are enclosed in double quotes.

Wikipedia has more information on standard issue license plates. Samples of current standard plates are available here, including Q's for CA, FL, GA, IN, IO, KS, ME, MI, MS, OH, OK, OR, RI, and TN; I's for GA, NE, and SC; and possibly an O for CT.

This site has some notes about invalid letters on standard issue passenger plates, including no I, O, Q, or U for Maryland; no O (or 666) for MS; no I, O, Q, or U for PA; and no I, O, or Q for VA.

While in Texas, I saw an Arkansas plate with an I.

(dLLLddd) All letters are used, but the I, O, and possibly Q are only found in the middle letter. The Q has an unusual shape. The first digit indicates the age of the plate (lower values are older).

"6RIT751", "3XOV871", "6SOX164"

(ddd - LLL) Uses 0 and O.

(dddddd) -- no letters.

Uses I, Q and U.

(LLL dddd) Uses Q
"ARQ 4169"

(LLL dddd) Uses I
"FIP 7374"

(ddd LLL) Uses Q and U
"RQJ 882", "845 CUL"

(dLL Ldd; LLL dddd) Uses Q and U, but not I or O. Does not use front plates.
"3KQ L39"

(LLL dddd) Uses I and Q
"EIY 6441", "DEQ 7994"

(ddd LLL) Uses Q.
"622 EVQ"

"SLI 061"

South Carolina
(LLL nnn) Uses I and Q

"GIQ 157"

(ddd - LLL) Uses Q.

I spent four days in Austin and never saw an I, O, Q, or U.
Texas may be avoiding all vowels.


"WLQ-804" is an old plate from 1989 that added new letters to expand available combinations

Thursday, March 25, 2010

Seeding March Madness

Each of the teams in the NCAA Men's Division I basketball tournament is seeded so that the best teams are likely to meet late in the tournament. In 1985 the number of teams was increased to 64, and a play-in game was added in 2001. There are 4 regions, and the strongest team in each region is given the 1 seed and the weakest the 16 seed. How well does the relative seeding of two teams predict the outcome of a game? It is well known that no 16 seed has ever defeated a 1 seed, but part of the attraction of the tournament is that the higher ranked teams do not always win. I have examined the results from the 2007 through (most of) the 2010 tournaments to learn the effectiveness of the seeding process. The first figure below plots the winning margin for the favored team versus the ratio of the seeds. For example, since in 2008 Kansas, a 1 seed, beat Davidson, a 10 seed, by 2 points, there is a point with an x-value of 10.0 (10/1) and a y-value of +2 (positive because the favored team won). I have ignored the 4 times when equally seeded team play, which can only happen when the regional winners play in the "Final Four". The plot shows that the favored team usually wins (about 75% of the time), and a linear trend line has a correlation coefficient of 0.30. But there is a wide range of winning margins -- typically about ± 20 points, and the range is roughly independent of the ratio of the seeds. This is why there are many upsets.

 The second figure shows the distribution of winning margins after correcting for the trend line.  The standard deviation of the distribution is 11.0 points, and by construction the histogram is centered near 0. The standard deviation without correcting for seeding is 131. points. Once the trend line exceeds 11.0 points (at a ratio of about 5.7), the favored team is very likely to win. In fact, there is only one example of such an upset in the above figure (9-seed Northern Iowa defeating the No. 1 seed Kansas in 2010). There may be factors other than seeding that correlate with the winning margin, but I have not investigated them.

Sunday, November 22, 2009

Swift 5-Year Conference Celebration

The Swift mission celebrated its 5th anniversary with a 3-day conference at the Pennsylvania State University. Since UVOT team had their own meeting prior to the conference, I spent the entire week in State College. This was an opportunity to sample the local restaurants including the Cozy Thai, the Indian Pavilion, the Golden Wok, Herwig's, and the Berkey Creamery. While returning from the Indian Pavilion, we passed the pig sculpture (photo below) celebrating the 100th year of State College. After the conference banquet Thursday night, many of us went to hear Maxwell Strait at the club Phyrst. The beer was cheap, the band was loud, the place was jumping,  cigarettes were found in surprising locations, and the band did not quit until 2 a.m. Their lead guitar player resembled the PI of one of the Swift instruments. Attendance was down at the start of the Friday morning session.

The final day of the conference was exactly 5 years after the launch of Swift, and several cakes (left photo) celebrated the occasion. For some reason, everyone wanted a picture (right photo).

Monday, November 9, 2009

Elihu Boldt Memorial Symposium

About 100 of Elihu Boldt's friends and colleagues gathered at the American Center for Physics in College Park, MD, on November 6, 2009, to celebrate his life and legacy. In addition to those of us from the X-ray Astrophysics Branch at GSFC (which Elihu founded), there were also friends from as far away as Italy and Mexico and several people who knew Elihu as a student at MIT. There were a series of short talks about the wide range of topics that Elihu worked on during his long career. I was honored to contribute a talk on Galactic Ridge X-ray Emission. Elihu first published a paper on the topic in 1969 and was still suggesting observations a couple of years ago. An agenda for the symposium and links to some of the talks are available here.

Wednesday, August 26, 2009

Mary Ann Mears Sculptures

Mary Ann Mears is a sculptor who lives in Baltimore, Maryland. Many of her sculptures grace public areas such as bike paths in Maryland (where I first encountered them), but they are also found in other states and even in Japan. The sculptures are typically large, brightly colored abstract shapes made of aluminum or steel. The table below provides information about all the public sculptures that I know about. Unfortunately, there are rarely expository plaques with the sculptures. Another list of her sculptures can be found here. There is now an official Mary Ann Mears web site with an extensive list of her sculptures at public and private sites including the new Spun Grace at St. Agnes Hospital in Baltimore.

This interactive Google map gives accurate locations for those in Central Maryland that I have viewed.

Click on the photo links to see images of the sculptures.

Title /
Location / (Marker on Google Map) Links Comments
Beacon 1

Metro Station


A major work in the large plaza at the station entrance.
Gyre & Gimble

Imagination Stage
4908 Auburn Ave.
Bethesda, MD

a whimsical collection of
Floating Garden
Spring 2004

3003 Hospital Dr., Cheverly, MD (C) information inside Cheverly Health Services Building

Southern Ave. Metro Station
Callooh Callay

Baltimore & Annapolis Rail Trail
Glen Burnie, MD

adjacent to bike path

Snowden Center
Oakland Mills Road
Columbia, MD

An odd, out-of-the-way location.
Red Buoyant

100 E. Pratt St.
Baltimore, MD
(across from Harbor Place)

Duplicated in Kawasaki, Japan
Red Buoyant II
June 1984

Nikko Hotel
Kawasaki, Japan
An expression of friendship
between Baltimore and Kawasaki
Northeast Middle School
Baltimore, MD

Ft. Worthington Recreation Center
Baltimore, MD
Notre Dame Prep School
Towson, MD

? White Marsh Mall

Conn. Dept. of Mental Retardation
Norwalk, CT

Oasis Diffraction
1219 Broad St.
General Assembly Hall
Durham, NC

a mobile inside the Hall
Sky Dancing
Student Recreation Center
UNC-Chapel Hill

Caged Heuristics
Meyerhoff Gallery

Friday, August 14, 2009

Another Year of No Mercy

The last regular game in 2009 for No Mercy, Building 2's coed team in the GSFC Slow-Pitch Softball Association, was Monday, August 10th. Once again the team avoided being "mercied" (the other team scoring 10 runs in one inning) for the whole year, although we did give up 7 runs in the first inning of the last game before coming back to make it a respectable 7 to 5 loss.

Surprisingly I played the whole year after sitting out 2008 with shoulder pain. Physical therapy followed by a steady regimen of exercises made throwing pain-free once again. As in 2007 and 2008, there was the traditional No Mercy cheer, and then a trip to Side Pockets to celebrate another season.

Two weeks later No Mercy played in the co-ed tournament with teams from both the Monday and Tuesday leagues. The games were shortened to 4 innings, and there were some minor rule changes to speed things up. We handily won the first game, but were shut out in the final games. Since our regular pitcher was unavailable, I pitched all 3 games. I set another personal record in the second game by giving up 3 home runs to the same batter. Two easily cleared the center field fence. On the second one, I gave the pitch the most arc ever, but he still crushed it. This adds to my other pitching "accomplishments": a 4-pitch inning and a full 7-inning game with no fielding chances. Sadly, it was the final game for our star "ringer", who is taking a post-doc position in Massachusetts. At least she went out with a bang -- a bases-loaded homer in the first game. We later gave her an appropriate send off.

Sunday, September 14, 2008

Atholton High School Soccer

My daughter is once again playing on Atholton High School's junior varsity soccer team. She played well (left photo) in the team's first three games and scored goals in each victory including a header against Howard High (right photo). The soccer program had its annual "play day" Saturday morning, Sept. 12th. Players from both the boys and girls teams, junior varsity and varsity (above photo), played 7 vs. 7 games all morning. Each team had players from all four school teams. There was a wide range of skills and sizes, but the ball was passed around to all the players, and a good time was had by all. At the end of the morning, the parents got to show their moves (at least what was left of them), and played the high school players to a nil all draw.