Ain’t I Got a Right to be Wrong?

Never Tell Me the Odds?

March 7, 2013 by Robert D. Brown Leave a Comment

In my last post, I discussed the meaning of expected value (EV) and how it's useful for comparing the values of choices we could make when the outcomes we face with each choice vary across a range of probabilities. The discussion closed by comparing the choice to play two different games, each with different payoffs and likelihoods. Game 1 returns an EV of $5, even though it could never actually produce that outcome; and Game 2 returns an EV of $4, also being incapable of producing that outcome. But let's say that you hate it when C-3PO tells you the odds, so you commit to Game 2 because … [Continue reading...]

Filed Under: Risk Analysis Tagged With: Analytica, expected value, Risk Analysis, uncertainty analysis

A Brief Explanation of Expected Value

February 8, 2013 by Robert D. Brown Leave a Comment

When helping people analyze the risks they face in complex decisions, I frequently receive requests for an explanation of expected value, as expected value is a measure commonly used to compare the value of alternate risky options. I've found that by now most people understand the concept of net present value (NPV) rather well, but they still struggle with the concept of expected value (EV)*. Interestingly enough, and fortunately so, the two concepts share some relationship to each other that makes an explanation a little simpler. NPV is the means by which we consistently compare cash flows … [Continue reading...]

Filed Under: Risk Analysis, Uncategorized Tagged With: expected value, Risk Analysis

Displaying indexes in balloon help

January 19, 2013 by Lonnie Chrisman Leave a Comment

In a meeting today, Paul Sanford suggested that it would be nice if Analytica would show the indexes of a variable when you hover over its node. "I know how I can do that right now," I volunteered. I thought I'd share this with other Analytica users here. The help balloon with my modification shows the indexes on the last line. The indexes come from the computed result, so it only shows them if the result is already computed. If the result has already been computed and is scalar, then it shows the value, allowing you to hover over nodes and see their scalar values (text or … [Continue reading...]

Filed Under: Analytica Tips and Tricks

Greenhouse Gas Emissions and Energy Expenditure from Santa’s global tour

December 20, 2012 by Lonnie Chrisman 1 Comment

In four days, Santa Claus will embark on his annual Christmas eve ritual, delivering presents to the good little boys and girls around the world. In this article, I look at the net energy expenditure and greenhouse gas emissions attributable to this magical tour. Many aspects of Santa’s amazing technology are not publicly available, so it will be necessary to make numerous educated guesses to complete the analysis. I will derive an estimate for the total distance traveled, velocities obtained, work expended to reach the implied kinetic energies and energy losses due to air friction. Then … [Continue reading...]

Filed Under: Energy Analysis, Green Analytics, News and Current Events

Odd Couples: How Ice Skaters and Fireflies Tell Us Something About the Language of the Universe

December 3, 2012 by Robert D. Brown Leave a Comment

Dark matter: Credit NASA, ESA and M.J. Jee, 2007. Hubble image from 2004.

The universe has always possessed the language it needs to conduct its own affairs. I don't think it could be otherwise. Because my daughter participates in competitive figure skating, my wife and I spend a lot of time at the ice rink. Well, to be accurate and fair, my wife spends a lot of time at the ice rink. Today is different. The recent Thanksgiving holiday activities disrupted regular free skate schedules, so I volunteered to take my daughter this morning to the special free skate sessions that were offered at the rink. Sitting in the upper bleachers where the air is a little warmer, … [Continue reading...]

Filed Under: Uncategorized Tagged With: Analytica, coupled oscillators, emergent systems, mathematics

Seeking Principal Analyst and Consulting Lead

September 14, 2012 by Nick Kretz Leave a Comment

Lumina is seeking an experienced consultant in energy or environment to be a leader in our consulting group. You must have: A graduate degree in science, engineering, operations research, or other quantitative discipline Several years experience working as a lead consultant in energy or environmental technology and policy. Outstanding analytic and quantitative skills. Outstanding communication skills in writing and working with clients. Experience building substantial computer models of real world systems. A passion for developing practical solutions to move our World onto a … [Continue reading...]

Filed Under: News and Current Events

Analytica 4.4.3 Patch Release

August 28, 2012 by Lonnie Chrisman 2 Comments

Today we announce the Analytica and ADE 4.4.3 patch release. The patch has an extensive number of fixes and improvements since the 4.4.2 release. We recommend that all Analytica and ADE 4.4 users install and start using 4.4.3. When you already have an earlier 4.4 installed, installing the patch takes about a minute. If you have an internet connection and use Analytica 4.4, it will automatically detect the new patch within the next few days, download the installer, and then the next time you run Analytica, it will ask you if you want to install it. To update ADE, or if you need to … [Continue reading...]

Filed Under: Analytica Tips and Tricks, News and Current Events, Software News

Fear and Loathing in Las Vegas with Reverend Bayes

August 6, 2012 by Robert D. Brown Leave a Comment

A trip to Vegas, an evil clown, a bizarre coin, and a minister. What could go wrong? I commented in a footnote of an earlier post that one of my favorite - no, morally obligated - questions to ask when faced with imposing assertions or risky plans is: “How do you know that?” If we could but practice the discipline to ask this question more often with greater courage and rigor, I think it would lead us to less intrusive and ineffective public policy decisions, assertions of power over those we distrust, or costly commitments to action based solely on untested gut feel or intuition … [Continue reading...]

Filed Under: Analytica Tips and Tricks, Risk Analysis Tagged With: Analytica, Bayes' Theorem, Risk Analysis

Desperately Diving for Pearls of Great Price

July 2, 2012 by Robert D. Brown 3 Comments

You would be shocked to learn how fast you can make it to the bottom of a lake with a cinder block tied to your leg. I know this rate, by my own empirical investigation, to be thirty feet per second, give or take. If you’re in the mind to disconfirm this experimentally determined value, I will tell you how to repeat this experiment for yourself. First, convince yourself there are freshwater pearls in the mussels that live in your grandfather’s lake… I grew up in a rural area of middle Georgia on my grandfather’s retirement farm. It wasn’t a big farm - sixteen acres to be … [Continue reading...]

Filed Under: Case Studies, Risk Analysis, Uncategorized Tagged With: Risk Analysis, uncertainty analysis