What to do when your model results are ridiculous?
Experienced analysts and modelers know that “Oh shit!” moment all too well. You inspect the first results from your new model and they are obviously wrong. They are an order of magnitude off from what you expected. Or...
More »Testing hypotheses about causation
In 2002, I developed a statistical framework for testing whether your data provides statistically significant support for the hypothesis that A causes B. I published only one conference paper with some colleagues on the idea before moving on to other things,...
More »Efficient estimation of the expected value of information (EVI) using Monte Carlo
The expected value of information (EVI) lets you estimate the value of getting new information that reduces uncertainty. At first blush, it seems paradoxical that you can estimate the value of information about an uncertain quantity X before you...
More »Lumina at INFORMS 2018 in Phoenix
We'll have a have a few events at this year's annual INFORMS meeting, held in Phoenix, AZ this November. In addition to our Lumina Decision Systems booth #56 in the Exhibition Hall (come by and say hello!), we'll...
More »How the strange Cauchy distribution proved useful
On Tuesday I had an interesting exchange with Jorge Muro Arbulú, a professor in Peru, about the Cauchy distribution, which also called the Lorenzian distribution. Unlike most probability distributions you encounter, the mean and variance for strange distribution...
More »Using Python to parse a Shapefile
A shapefile (*.shp) is a binary file format used by Geographic Information Systems (GIS). I used an existing Python library (Fiona) to read and parse a shape file, and then imported that data into Analytica. Here I'll show how...
More »How to call a Python function from Analytica
I found it pretty easy to call a Python function from Analytica using COM automation. The COM integration functionality comes included with the Analytica Enterprise edition. In this blog posting, I'll show you the basics...
More »Analytica and Cognitive Radio
The more I learn about our Analytica users, the more I discover that "those who like it, like it a lot" (to borrow a slogan from a brewery back home in Canada). I would add "those who like...
More »World Cup Soccer. How much does randomness determine the winner?
Yesterday France beat Croatia in the World Cup final. Congratulations to France for winning the world championship! And also to Croatia for making it to the final after a spectacular sequence of surprise upsets! Also yesterday, I overheard...
More »How to limit entry to specific cells of an edit table
Netflix's basic subscription plan was introduced in May 2014. In a Netflix business model that I created, I have an edit table where I can enter the number of subscribers of each plan time in each month. Since the...
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