80% Now or 100% Later

Given a choice, should you take the 80% solution you can do now or the 100% solution you have to wait for?

The bottom line here is, clearly, available time and effort. Assuming you have the resources to make either happen, it comes down to which one can you get done prior to any relevant deadlines and whether or not the difference in time and effort will impact negatively other projects (recall the 80/20 Rule).

The awful truth is we don't always get to do the best thing every time nor can we always put out our best effort on what we do. A simple example is this: you have two projects to get done, A and B. Project A is due in a week, Project B is due in 10 days (calendar days and weeks, not business days and weeks). Project A needs a week's worth to do really well, but three days to be a satisfactory result. Project B has the same setup. Late is very bad (like you don't get paid, lose a contract, or fail a class). What do you do?

I'd plan for eight days days of work (four days in on each) and have an extra "emergency" day for each and live with a better than minimal but less than optimal result on both. Should I get more done than I thought, that's great (but not likely). On the other hand, I have two days to help get all the requirements met to at least a satisfactory level.

How does this relate? 80% now versus 100% later is all about priorities and bottom lines. In the above case the point is get the job done, not get it done perfectly. It says, in short, take what you can get and move on to the next priority item. It is, in short, slash and burn project planning.

Sometimes its more important to get the job done than getting it done well.

Random Chat Connects

Perhaps my largest problem with IM is the inability to know who you're talking to without some other form of either authentication or identity confirmation.

For instance, this afternoon two people contacted me on IM who refused to give their real name (one was posing as Hillary Clinton . . . ) or a legitimate reason contacting me (not an exclusive or). It's just common courtesy to provide one or the other. Anyone who doesn't do one or the other I block out of hand.

My best advice: get in touch via another method first, then if warranted go for chat. For instance, I am on the Ubuntu Forums and have my IM's up. If you want to IM me to ask an Ubuntu question, please PM me through the forums first with an explanation of why and the nick you'll use to contact me so when you IM me I know not to kick you out of hand.

Bilingual Programming

For class I'm being made to code in Mathematica, but I'm most conversant in R and actively using it in parallel for a research project. The problem I'm having is every time I get told to code something, I immediately think of how to do it in R and all the "extra" features I'd build in to make things easier later by subsuming more of the work into the method.

I can't image working in three or four or even five languages in parallel. Hopefully it doesn't get any worse.

Seeing Parrallels

As I sit here in my Applied Mathematics course learning about cumulative energy, Shannon Entropy, and wavelets, I'm starting to see some parallels to statistics. Cummulative energy looks like a Cumulative Density Function. Shannon Entropy looks like a Likelihood function (of sorts). Maybe if I knew more about statistics, probability, and information theory I'd understand what is is that I'm looking at.

Grrr . . .

Bang Per Buck in Carbon Emission Reduction

In economics, there's a principle colloquially known as the "Bang Per Buck" principle. In short, at the equilibrium (also the maximum profit/utility), the cost per additional unit of every output is equal.

It turns out there is nothing special about this fact. The mathematics indicates it's true for any local maximum or minimum. So, if we want to get maximal carbon reduction, we need to adjust the mix of measures until the cost per unit of additional reductions is equal across all methods. In this way we can be confident we're getting the most reduction for our money.

In practice, the way to do it is to start with those approaches which cost least per unit of reduction until it's equal to the next cheapest and then use whichever one of those is cheapest and so on. If you're buying sponges on a budget, all the sponges are equally good, and you need more than any one store has, then you start at the cheapest store (ideally taking transportation and time costs into account), buy them all, and then move on to the next cheapest store. What works for sponges works for carbon.

So before you go out and buy yourself a $4 lightbulb, at least do this math:

1. Add up how much the old fashioned kind would cost over the expected life of the $4 bulb.
2. Add up the energy cost of using those old bulbs.
3. Add up the energy cost of the $4 bulb.
4. Add lines one and two. Call this "A".
5. Add $4 to line 3. Call this "B".

B-A is the total cost you are paying for any extra environmental benefits, at least in terms of the price you pay for bulbs. I sincerely hope sincerely the number is negative, because then you are being paid (over the life of the bulb) to be more energy efficient and reduce your carbon footprint.

Constant Temperatures Means no Warming? A Question of Type-2 Error

I just heard on the radio today global temperatures have been statistically stable since 2001. As someone who said he's become a believer, what am I to make of this?

I'll admit I'd like to know what the margins of error are. I'll also admit those errors are type-1 errors (they measure the probability that we falsely reject the null hypothesis of no change) and are not reflective of the error that we incorrectly reject the alternative, that warming is happening.

Do I like that we don't know the type-2 error probabilities? No. On the other hand, I know mathematically it has been minimized though the use of valid statistical testing. But remember--"minimized" could mean a 95% of incorrectly saying there is no warming.

It's time we remember R A Fisher established 95% Type-1 errors as significant without any hard statistical reasons. Of course, the above link also notes there is a case to be made for a line in the sand (although 95% is merely one line amongst many we could chose), I would argue it is not as important to stick dogmatically to one line in the sand as to simply be clear about the significance level of the results and let the user draw their own conclusion. Perhaps I am, given my ambivalence about Type-2 errors, ready to accept global warming at the 90% or even 85% levels.

PT This Morning

Odd workout today.

1.5 mile run in 9:51
85 sit ups
71 push ups.

If your guessing it was max each, you'd be right. This was for an evaluation, so I rested the last few days.