Sunday, August 16, 2009 7:53 PM
F# Discoveries This Week 08/16/2009
This week we have some user group meeting announcements, WPF dependency properties, first class composable events, and a few interesting statistical modeling techniques.
We'll be having an interactive, hands-on session where we'll actually get to code some F#. All levels of knowledge are welcome, and there will be food!
Robert Pickering will be speaking on why F# is the way it is.
This is a quick post demonstrating how to create WPF Dependency Properties in F#. There is a bit of a trick to it as you have to use the val keyword to define a field and that field must be mutable and you also have to use explicit interface access.
Event-based programming is a pretty common scenario in .NET programming today, especially used in user interface programming. These events are a way of a class to notify when something of interest happens to an object, such as clicking a button on a form. Just as you would do in C#, programming with events is fairly straight forward to add and remove event handlers from an object.
In the general linear regression model, one of the assumptions is that the variance is constant across all observation points.
The question here is to see how sensitive coal consumption is the relative price of coal versus natural gas. For example, it is interesting to know how easily electric utilities can swap coal for gas depending on their relative prices.
In my last post I set up an example dataset and then showed how use the Durbin-Watson statistic to test for serial correlation. Once we have recognized that serial correlation exists, we need to make the appropriate adjustments because OLS is no longer the best estimation technique. We need to rely on GLS to perform our estimation.