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Decision trees and self-challenges: how my laptop’s recent battery failure is a great excuse to think

The battery on my Lenovo X61 tablet refuses to hold a charge, and there seems to be no way to fix it. The battery is no longer covered under warranty, so I’ll need to replace it on my own if I choose to. An easy algorithm for decision-making is be to postpone spending money until I can demonstrate really good benefits for doing so. (Or in this case, nine business days before I really need a new battery.) Because I’m curious about the way I might think about other choices, I’m going to think through some of the strategies I use to make decisions. =)

Decision trees

I like breaking things down into decision trees, similar to the technique described by Ken Watanabe in his kid-friendly book Problem Solving 101. It’s useful to figure out what the options are and what their costs and benefits might be. I realized that I actually have two independent choices: what to do with the battery, and what to do with the laptop. Here is my current decision tree.

  • CHOICE A.1: Buy a new battery for my Lenovo X61T
    • Will need this if I sell or give the laptop to someone
    • CHOICE A.1.1: Lenovo battery
      • CHOICE A.1.1.1: Lenovo.com – trustable but more expensive; $160-200
      • CHOICE A.1.1.2: Craigslist – potentially $80-100, risk of getting older batteries
      • CHOICE A.1.1.3: Other Internet sources – risk of getting the wrong kind of battery
    • CHOICE A.1.2: Third-party battery $70-90 – risk of scams, unreliable batteries, hazards
  • CHOICE A.2: See if I can get by without one
    • Make my work laptop my main laptop for the moment.
    • Draw with the power cord plugged in.
    • Keep track of the instances when I’d like to plug in, and buy the battery when it gets on my nerves or when I notice myself using the computer much less. Currently using the tablet practically every day, so drop-off should be noticeable.
  • CHOICE B.1: Save up for X220 tablet
    • Longer battery life
    • 12.5″ outdoor-viewable display, more horizontal resolution: 342 extra pixels, widescreen aspect ratio
    • 3.9 pounds with 4-cell battery
    • Dual-array digital microphones – possible use for Skype, podcasting?
    • 2.7 GHz processor option
    • Rapid Drive for faster bootup/access?
    • Instant resume for wireless (up to 99 minutes)
    • Warns when walking away from stylus (heh, nifty; haven’t lost mine yet, though)
    • Gorilla Glass – scratch-resistance could be useful
    • CHOICE B.1.1: Give X61T to J-
      • May still need to buy a battery unless we want to treat it like a PC.
      • She’ll like the drawing bit.
    • CHOICE B.1.2: Resell X61T on Craigslist
      • Will need new battery anyway
      • Will need to sell at a discount because of wear and tear
  • CHOICE B.2: Stick with X61T until I reach the end of my two-year self-upgrade cycle, or until I have strong reasons to upgrade
    • 4.2 pounds, UltraBase, etc.
    • Doesn’t use new buttonless trackpad
    • Bigger wrist rest space
    • Could potentially scoop up X220T on secondary market, or wait for promos

I’m probably going to go with choice A.2 for the short-term choice, and we’ll see how my savings work out for choice B. We’re saving for a fair bit of travel this year, so B.2 is more likely than B.1. Fortunately, I work with two laptops, so it’s fine. My basic choice is good. Here’s another technique I use to examine that more closely:

Estimating option value

Hmm. Well, I can still use my battery-less X61T for drawing, writing, and coding. I’ll need to properly hibernate it before transferring locations, or leave it mostly in one place. I just won’t use it out and about as much. I don’t spend that much time in cafes, so it’s really more the shift between the kitchen and the living room or the basement.

So, what’s the estimated gap between the expected value of a fully-functional laptop and a battery-less one? In my case, probably not as much as it would be for other people, because I’ve got my work laptop in addition to this. The upper bound on value for me must be $5/day – definitely can’t be more than that, and is probably nowhere near that number. The cost is probably just a few more extra minutes starting up and shutting down, and a little less flexibility, which doesn’t translate into a large cost because I can use that time for something else. It might even be a net benefit if it encourages me to use a sketchbook during our upcoming trip. =) Worst-case scenario is that it might cost me an hour of work if I forget to save something, but that’s just about discipline.

The value gap might be bigger for J-, but we’ll see if she can handle it. It’s going to be a big gap if we sell this, but then it’s okay to get a new battery closer to that day. Besides, I usually run my laptops into the ground anyway. This one was an exception. I replaced my Eee after a little less than a year), but that was mainly because J-’s need for a computer coincided neatly with my curiosity about tablet PCs.

Setting up challenges

Another way to find out if I’m sufficiently interested in something is to ask questions and set myself challenges. For example, if I want to double-check the potential benefits of the fancy new X220 tablet compared to, say, the lower-prices X220 laptop or my current X61T, I can ask the following questions:

  1. Will I draw often enough to make the tablet worthwhile?
  2. Will I need more than 3 GB often enough to make the upgrade to a 64-bit OS worth the hassle?
  3. Will I run into CPU processing limits often enough to make sense to switch?
  4. Will I need the battery life often enough to make the extended battery life worthwhile?

Answers 2 and 3 seem to be “no” at the moment. VMs would be a good use of additional memory and processing power, but I’ve been doing fine with two computers. If I can cope with a battery-less life, the answer to 4 is probably not significant, unless I find myself going to way more conferences and meetings (and if my scanner proves unwieldy). The answer to question 1 is the most interesting.

I’ve taken lots of sketchnotes, but I’ve done fewer illustrations than I’d hoped I’d draw with the X61T. The workflow isn’t as smooth as keyboard + Cintiq, but it’s (semi-portably) fun. I haven’t figured out how to stop GIMP and Inkscape from jittering so much, although MyPaint and OneNote make beautifully smooth lines. I tend to do my sketchnotes plugged in, but I have a few sketchnotes from meetings where power outlets were few and far between. If I use paper notes for the portable sketches (maybe index cards or notebooks?), then I’ll get a better idea of the incremental value of A.1 or B.1. I can set myself an arbitrary threshold – maybe fill a notebook full of out-and-about sketches and notes – and reconsider my decision when I’ve achieved it. Result: Better drawing skills, a habit of drawing, and an idea of how much I might benefit from the infinitely scrollable paper and the multiplicity of colours on a digital canvas.

I’ve exaggerated the level of thought I usually go to for something like this. There’s room in my “dream/opportunity/kaizen” fund for a new battery if it turns out I absolutely must have one. But it’s fun to think through the techniques I might use to decide something, and writing it down now for something that isn’t critical may help me remember it later when I need to decide something more major. And who knows, it might get you thinking about something… =)

(I might end up getting a lot of value out of not having a battery for this notebook. Look, a blog post, and more reasons to draw/sketch on paper! Stay tuned for progress.)

More thoughts on time analysis: correlations and revealed preferences

People often ask about the time analyses I do as part of my weekly review. My weekly time tracking reports go back to about December 11, 2010, when I started tracking my time using the free Time Recording app on the Android. I do it because of the following reasons:

  • I need to track my project-level time for work anyway,
  • I want to see where I spend my time and if that’s in line with my priorities,
  • I want to know how much time it takes me to do certain things, in order to improve my estimates and get better at planning,
  • I want to avoid burning myself out
  • I want to make sure I allocate enough time to important activities instead of, say, getting carried away with lots of fun work and flow experiences, and
  • I want to cultivate other deep interests and relationships.

Fatigue and burnout are particularly big concerns for developers. There’s always the temptation to be unrealistic about one’s schedule, either through over-optimistic estimates or through business pressures. However, sustained crunch mode decreases productivity and may even result in negative productivity. Sleep deprivation severely cuts into cognitive ability and increases the chance of catastrophic error. I like what I do too much to waste time burning out.

Development is so engaging for me. I could keep writing code and building systems late into the night, at the expense of other things I could do. Tracking time helps me keep a careful eye on how much time I spend programming. Like the way a good budgeting system helps me make the most of my expenses and gives me the freedom to take advantage of opportunities, a good time budgeting system helps me make the most of my focused work time and allows me to also focus on other things that matter (the care and feeding of relationships, the development of new skills, and so on).

So here are some new things I’ve learned from time tracking:

  • I sleep a median of 59 hours a week, which is about eight and a half hours a day. This is more than I expected, but I manage to get a lot done anyway, so it’s okay.
  • I work a little over 40 hours each week, except for the occasional week of crunch time or travel. I don’t make a habit of 50-hour weeks, and I get a little twitchy when I work too intensely several weeks in a row (46 hours or so). This means that when I estimate timelines or project my utilization, I should assume 38 or 40-hour weeks instead of 44 hours.
  • I spend most of my time sleeping (44%), working (31%), or connecting with people (11%). Regular routines take up 9% of my time, while my favourite hobby (writing) takes only 5%. I enjoy my work and I sleep well at night, so this time allocation is fine.

In economics, there’s the idea of a revealed preference, which is basically what your actions show compared to what you might say or think you prefer. I may think I’d like to sew or learn languages or do the piano, but if I spend time playing LEGO Star Wars III instead, then that tells me that sewing, Latin, and Schumann are lower on my priority list. (Rationalization: LEGO Star Wars is awesome and it counts as bonding time with W- and J-, so it’s not all that bad.)

So, how do I really trade my time? Which activities are positively or negatively correlated with other activities? I made a correlation matrix to see how I spent my time. I used conditional formatting to make high correlations jump out at me. I found some interesting patterns in how I shift time from one category to another.

Activity 1 Activity 2 Linear correlation coefficient (r) Notes
Prep Personal 0.87 Getting things in order means I can give myself permission to learn something new
Cooking Prep 0.86 Makes perfect sense. Big chore days.
Break Drawing 0.75 More relaxing time = more drawing time
Travel Work 0.69 When I commute to work, I probably tend to work longer. Also, I needed to go to the office for some of the crunchy projects.
Sleep Break 0.67 Relaxed days
Sleep Writing 0.60 Nice to know writing isn’t conflicting with sleep
Social Drawing -0.50 The Saturday afternoons or weekday evenings I spend with people instead of sketching
Routines Drawing -0.65 Lots of chores = less drawing time
Personal Drawing -0.55 Learning other things = less time spent on drawing
Travel Cooking -0.60 Lots of travel = live off home-made frozen lunches
Sleep Cooking -0.62 Late weekend mornings = less cooking?
Sleep Prep -0.58 Likewise
Sleep Personal -0.57 More sleep = less time spent learning other things

I can guess at the causality of some of these relationships, but the others are up in the air. =) Still, I’m learning quite a lot from this exercise. For example, I thought I was giving up sleep in order to write more or draw more. It turns out that sleep cuts into cooking, prep, and other personal interests (sewing, piano, etc.), and doesn’t have much effect on work, writing, or drawing. I do sleep quite well, though, so it may be interesting to experiment with that.

I’m also happy to see I don’t give up too much because of travel – a median of 3.4 hours / week, much of which is spent reading, brainstorming, or listening to audiobooks with W-. Travel time reduces cooking time, but that’s okay because we batch-cook in order to minimize weekday cooking. It’s good to see that it doesn’t affect my other activities a lot.

The same dataset lets me analyze my sleeping patterns, report project-level breakdowns at work, and review quick notes on my day. I’m in consulting, so I need to track and bill my time per project. Time Recording makes it easy to do that, and I’m thinking of tweaking my workflow further so that I can use task-level times to improve my estimates.

So that’s where I am, tracking-wise. It takes me a few seconds to clock into a new category, and the habit is handy for making sure I know where my phone is. Tracking my time also helps me stay more focused on what I’m doing. If you’re curious about the idea and you have a smartphone or other mobile device, find a time-tracking application and give it a try. Have fun!

2011-03-29 Tue 21:54

Spousonomics: Using economics to master love, marriage, and dirty dishes

I love research-backed books that help us understand why we do what we do. Paula Szuchman and Jenny Anderson’s Spousonomics: Using Economics to Master Love, Marriage, and Dirty Dishes was no exception. The book takes a look at common marital conflicts and situations, showing the underlying economic principles that influence our actions. For example:

  • Division of labour: Splitting chores equally may not result in the most efficient or the happiest of marriages. Specialize, remembering that payoffs can change over time.
  • Loss aversion: People hate to lose, which can result in really drawn-out fights. The advice to “never go to bed angry” can backfire. It’s okay to have time-outs.
  • Supply and demand: If you want something to happen more often, don’t make it costly or risky.
  • Moral hazard: It’s easy to take good things for granted. It’s also easy to end up trying to avoid any sort of conflict. The sweet spot is in the middle, where you’re not taking your relationship for granted, but you’re not paranoid about your spouse quitting.
  • Incentives: Think about the incentives you use and if they’re really effective. Trust can be much more useful than nagging.
  • Trade-offs: Think at the margin: consider the costs and benefits of small changes. Ignore sunk costs when making decisions. Get over the “it’s not fair” fixation.
  • Asymmetric information: Communicate clearly. Don’t play games by hiding or withholding information. Figure out the essentials of what you need to share so that you don’t overload your spouse.
  • Intertemporal choice: It’s easy to make good decisions for the future, but hard to stick with those decisions in the present. Use commitment devices to help you stick with your resolutions or good ideas.
  • Bubbles: Non-bubbly married life is normal, so don’t stress out if you’re no longer infatuated. Beware of being unduly influenced by groups – just because everyone else seems to be doing something doesn’t mean it’s right for you, too. Don’t get overconfident.
  • Game theory: Don’t let the urge to retaliate or overcompensate lead to you to wildly polarized positions. Work together to get optimal results, not just individually-optimal results, and use commitment devices to help you stick with it.

The book goes into far more depth, and is an excellent read. It’s illustrated with case studies (problem couples who usually end up patching things up) and lots of research.

Here are some thoughts I particularly like:

If there are areas you care about but you feel helpless in, put in the time and effort to develop the comparative advantage in at least one of them. The authors tell the story of one economist who put the time into at least learning how to bathe an infant so that his wife wouldn’t end up with all the child-rearing tasks – and so that he wouldn’t get tempted to take advantage of that kind of a division.

Looking for things to read? In terms of marriage research, I’d recommend “Spousonomics” and Susan Page’s “The 8 Essential Traits of Couples who Thrive”. What do you like?

Using behavioural economics to motivate yourself when working on risky projects

We’re scrambling to respond to a request for a proposal (RFP). We’re not sure if the RFP is a formality and the client is already planning to choose a different vendor, or if it’s a real request, but the powers that be say it’s worth exploring. My manager thinks it’s a good opportunity to develop architecture skills. I like working above my pay grade, so I’m doing this even if it means stretching quite a bit.

It’s interesting to see the applications of the behavioural economics principles I’ve been reading about in “The Upside of Irrationality.” For example, there’s a chapter on finding meaning in work. The perceived meaning of work greatly influences our motivation to do it. If you know there’s a chance your work will come to nothing (cancelled projects and so on), you might be less motivated to work on it, and more drawn to projects where you think you’ll make a difference. Makes sense, right? (Ah, that’s why school projects bored me…)

Recognizing this bias means that I can understand my motivations and tweak them. It’s natural for me to want to spend more time on my other project. I experience flow on it – meaningful engagement. Although this proposal is riskier and I more often run into the limits of my understanding, it needs to be worked on.   Here are some possible approaches for motivating yourself when working on risky, uncertain projects: 

Break it down into small wins and celebrate those. Don’t wait for that all-or-nothing decision. You might not even reach it. Instead, work in stages so that you can successfully complete and celebrate each step. Share as much as you can during the process, too, while you’re excited about what you’re accomplishing. It’s much harder to harvest assets when you feel like a failure. 

Exaggerate the odds of winning. Irrational optimism can be useful. Imagine that you’ve got a great chance of succeeding, and you just might. You’ll still want to have a backup plan in case you lose, of course.  

Focus on additional benefits. For example, whether or not you succeed on a stretch assignment, you’ll still learn a lot. Can you find meaning in the skills and relationships you’re building and the experiences you’re collecting? 

Balance speculative or uncertain work with solid contributions. Spend some time working on things that make you feel happy and fulfilled. You’ll have the energy and confidence to tackle new challenges. 

How do you keep yourself motivated and focused when you’re not sure of results?

Mr. Fluffers: Stray or not stray?

I have a soft spot for cats. Our cats are all indoor cats, never allowed out except on a leash. There are a number of neighborhood cats who turn up on our deck for food or company. Some of them are definitely housecats let loose to run outdoors. Others, we’re less sure about. Housecat or stray? It can be hard to tell. We feed them some food, set out water, pet them if they’re amenable. Sometimes they even get dishes of warm milk.

Of the cats who visit us, we think one cat is either stray or somewhat neglected. Mr. Fluffers (as J- has named him) is a collarless gray tuxedo medium-hair domestic cat and a regular visitor. Medium-hair cats need a lot of brushing to keep their coats unmatted, and Mr. Fluffers obviously hadn’t been brushed in a while. W- combed away many of the mats in his fur, and even trimmed the most stubborn ones. But if Mr. Fluffers is a stray or neglected cat, it would be good to have that situation sorted out.

We’ve been thinking of taking Mr. Fluffers to the vet or to Animal services to have him scanned for a microchip, but we need to think through the decision tree first.

  • If Mr. Fluffers has a microchip
    • If the registered owners are reachable
      • Hooray! Cat reunion, or at least clarity on the situation
    • If the registered owners are not reachale
      • See decision tree for no-microchip case.
  • If Mr. Fluffers does not have a microchip
    • Take him to Animal Services as a lost pet?
      • Owners who lost him may not claim him there, considering impounding fee
    • Check for spay/neuter and then release him back into the neighbourhood?

For Mr. Fluffers and other potentially stray cats, I’m tempted to try the first step of attaching a safety collar with a tag that says: Not a stray cat? Please call us at XXX-XXX-XXXX… =)

2011-04-10 Sun 11:18

Stuff or experiences

Soha wanted to know what I thought about the differences between spending on stuff and experiences. This took me several drafts to figure out, and I don’t think I’m all the way to a clear understanding yet, but I’m trying to say something I haven’t really found in the personal finance books and blogs I read.

Stuff or experiences? Neither. It’s a false dichotomy, and one that often starts with the wrong question: “What will make me happy?” If you aren’t happy, it’s very difficult to buy happiness. Probably impossible.

What will make me happier than I am now?” – is that a better question? Not really. What’s “happier”, anyway, but something that draws an ever-moving line between you and some ideal?

I like this question instead: “What do I want to learn more about?” No guarantee of happiness, no pursuit of happiness, just curiosity. Happiness doesn’t have to be pursued. It just is. Happiness can be a chosen, developed response. So what I decide to spend money or time on is determined more by what I’m curious about.

I confess to having a strong distrust for people trying to sell me ways to happiness. A designer handbag won’t make me happy (or happier). Neither will a three-week vacation of idle relaxation on a pristine beach. Quite possibly even an enlightening weekly course on meditation wouldn’t do the trick. My life will be a good life even if I never stay in the best suite in a five star hotel, see the aurora borealis, or learn to fly a plane (ideas from Richard Horne’s “101 Things to Do Before You Die”, which does have amusing forms). It will simply be different if I do, and that only matters if I can do something with the experiences and ideas I pick up and recombine.

In fact, I’d rather spend on stuff – the raw ingredients of an experience – than on pre-packaged experiences. I’d rather spend on groceries for experiments than on a fancy meal at a restaurant or a cooking class with a famous chef. I’d rather spend on lumber and tools to build a chair, than spend on a cottage rental. Turns out this is based on sound psychological principles: we value what we work on more than what we buy. (For more on this, read Dan Ariely’s “The Upside of Irrationality.”)

You can’t untangle good stuff from experiences. The bag of bread flour I buy leads to the experience of making home-made buns, the experience of enjoying them with W-, and the lasting enjoyment of developing skills and relationships. Fabric and thread become simple gifts accompanied by stories.

Besides, it doesn’t have to be the question of what you want to spend money on. That’s just a matter of budgeting. Many things are possible, but you may save up a little longer for things that require more money. What it really comes down to is a question of time: do you want to do this more than other things you could do? (For example: yes to cooking and gardening; a theoretical yes to improv, but it’s not as high as other things on my list, so I focus on other things; no to the massage deals I see on dealradar.com when I wander by.) If yes, then budget appropriately. Don’t get distracted by low-cost, low-value activities or expenses. (Or worse: high-cost, low-value ones.)

If you feel you’ve made a mistake about spending, don’t beat yourself up over it. Learn and make better decisions next time. Not saddling yourself with consumer debt helps, as debt has a way of multiplying regrets. Stuff can be second-guessed more than experiences can, but it’s even better to break the habit of second-guessing yourself. Think of your sunk costs as tuition. You’ve paid for the learning, now go and use it.

Money can be considered in terms of time, too. Is the incremental benefit you might get worth the opportunity cost of enjoying other things earlier, the compounding growth you may give up, or the corresponding days of freedom in the future? (For me: yes to some wedding photography in order to reduce friction, but no need to get the top wedding photographer; yes to a wonderful bicycle I feel comfortable with; no to the latest version of the Lenovo tablet, although I may reconsider in a year or two.)

Stuff or experiences? Start with what you want, not what other people want to sell you. Treat it as an ongoing experiment. Evaluate your purchases and improve your decisions. Think about what you want to spend your time on, not just money. Good luck!

2011-04-24 Sun 16:45