Catherine Hood Consulting

Welcome to the first quarter 2013 newsletter from Catherine Hood Consulting.

X-13ARIMA-SEATS

The U.S. Census Bureau has released to the public X-13ARIMA-SEATS.

The biggest difference between X-12 and X-13 is the capability to generate ARIMA-model-based seasonal adjustment using a version of the SEATS procedure originally developed by Agustin Maravall at the Bank of Spain. However, all the original capabilities of X-12 are still in the program, including the non-parametric adjustments from the X-11 procedure, regARIMA modeling, and all the diagnostics.

We are currently working on updates to the web pages to reflect the addition of X-13ARIMA-SEATS to the arsenal of seasonal adjustment programs. We are also working on updates of our documentation to help everyone get started with the new program.

Fun Facts for March

As a mathematician, one of my favorite not-official holidays is Pi Day. This holiday only works in the United States because, in most other countries, the 14th day of March is written as 14/3. However, in the U.S. where we put the number of the month before the day, we happily celebrate 3/14 (or 3.14) as Pi Day. In the Hood house, Pi Day is celebrated by eating as much round food as possible, including cinnamon rolls, cookies, and pizza. One of our favorite Pi Day dishes is a ravioli casserole made with round cheese ravioli, pepperoni, and zucchini cut into circles. Yum!

March 15 is the Ides of March, made famous by Julius Caesar. (Or maybe by William Shakespeare?) Did you know that April 15th is not the Ides of April? The Ides was one of three dates each month (the Kalends, the Nones, and the Ides) calculated for the Roman calendar. The Kalends always fall on the first of the month. The Nones fall on the fifth of the month, except as described by the following poem:

• In March, July, October, May,
• The Nones are on the seventh day.

The Ides fall eight days after the Nones. Therefore, the Ides generally fall on the 13th, except in March, May, July, and October.

Comments?

Comments and suggestions are welcome. Please email "info" at catherinechhood.net with your ideas.