13 March 2019

Voting Systems

Ranked Choice (RC) vs Instant Runoff (IRV) vs Approval

RC and IRV are technically different. RC is a way of expressing preference, IRV is a method of tabulating votes from RC ballots.

This is an important distinction.

IRV, which seems pretty good can solve one problem (e.g. Gore v Bush) but introduce others. Technically IRV is nonmonotonic. That is, a shift of public opinion toward a candidate can cause that candidate to lose, and a shift of public opinion away from a candidate can cause that candidate to win.

A different and probably superior method is one called Condorcet. It eliminates most of the IRV issues but introduces a few other, but less likely, issues. IRV is to Condorcet as single elimination is to round robin.

Superior to both of them is Approval voting, in which you select all candidates that would be acceptable to you. It’s simple to tabulate and does not have the issues of either IRV or Condorcet.

There’s a website that has wonderful graphics of how these different systems can work or not depending on the positions of the candidates. http://zesty.ca/voting/sim/

The author of the site is Ka-Ping Yee.

Our election method makes it virtually impossible for third parties to gain a significant foothold. The electoral system is an added complication for presidential races, but the same holds true for state and local races as well as primaries with crowded fields.

25 January 2019

CPAP Machines and Taking Control of Your Health

In 2010, I wrote about CPAP machines and sleep apnea.

I wanted to update things, much has happened since then.

First, I got a new machine in 2013 immediately before a move to Houston from Oakland. The former machine was pretty old, and it was time for an update. I got my sleep test, found a mask that I really liked, and changed from CPAP to APAP.

CPAP is Continuous Positive Airway Pressure, APAP is Automatic Positive Airway Pressure. With CPAP, the pressure is set at a constant level and stays there until the machine is shut off. APAP, on the other hand, has a range of pressures over which it operates and increases the pressure the minimum amount required to prevent apnea. The advantage of APAP for users is that it is more comfortable to sleep without continual max pressure, which allows for higher pressure on demand.

The doctor prescribed an APAP and set the pressure range from 5 - 15 psi. The sleep test showed that 15 psi would be adequate for me. I received the machine only a few days before we left to drive to Houston.

The New Machine Isn't Working
I tried the machine the first night and it worked fine. But the second night.was horrible! Every time just as I was going to sleep, my airway closed, and it woke me up. Once that happens a few times, I can't even try to sleep again. I called the sleep doc the next day who looked at the data from the machine. His response was that it all looked fine. (apparently, as long as you have fewer than 5 apneas per hour, it is considered successful). When I pointed out that I only slept for one hour or something, he kind of shrugged.

He was kind enough to write me a prescription for Provigil in hopes that I didn't die on the trip to Houston.

The first night we stopped in Reno. We had gotten a late start and Reno worked for us. My machine worked a little better and we set out for Salt Lake City. Between Provigil and taking cat naps in the car, I was pretty alert and the day went well.

The Crisis
We arrive at the hotel, and I started to look for my APAP mask. Well, it was white, and the only thing we could figure is that I had left it on the sheets in the Reno hotel. Now the fun began. I started making calls and searching the net looking for help with someone who could provide the mask (we were not driving back to Reno).

Finally, I found someone, they sold me one. All good.

The Insights
But, in the process of looking for the mask, I ended up talking to a number of pretty knowledgeable APAP machine techs. I got a really important insight from one of them. If the low pressure is set too low, sometimes the machine can't ramp up the pressure fast enough to open the block. That fit perfectly with what was happening on the night I didn't sleep. I asked how I could adjust the pressure and he couldn't give me that information because it was only for doctors and techs to set that. I believe he told me that it was illegal for patients to program their own machines.

The Challenge Successfully Accomplished
I took that as a challenge. If that tech manual existed on the internet I was going to find it. I started digging and exercising my considerable google-fu skills. I finally came across a website called The Apnea Board.

They have a list of manuals and even a page with instructions on how to get into the clinician settings for a number of popular machines.

There's also a link to download software that can read your sleep records from your machine. I use Sleepyhead software. Here's a link that may work only of you register with the Apnea Board.

So using the software on my mac and tracking my results, here is how I have progressed.

You can see the progression from the original 5-15 psi setting on the bottom. My Apnea-Hypopnea Index was up there around 2-5 originally. When I started my own therapy, it immediately went to 1.47, and it has improved since. AHI is how many apneas or hypopneas you have every hour. My current rate of 0.42 means that I have one event every 3 hours or so. Remember, my doctor thought my initial settings were fine. I'm killin' it.

The FL column is flow limitation and my new machine does not measure that metric, so the zero is not meaningful.

Recent Changes

The machine I had at the start was getting old and you can get a new one every 5 years on insurance. I wanted to have a spare because I really rely on the machine and a week or longer without it would be bad.

I initially tried the same brand as I had, but an updated model. I previously used a Phillips Respironics System 1Remstar Auto with A-Flex. I tested a Philips Respironics DreamStation for one night, which worked really well. It is the brightest green one on the above chart. It had a problem though. It was extremely noisy.(1) I took it back and got the Resmed Airsense 10 Autoset and have been very happy with it.

The E4E Take on This
  1. My doctor did not understand APAP technology well. He went by the book and as long as the metric was ok, he was happy. It wasn't good enough for me.
  2. Don't believe BS from people who don't know what they're talking about. Just because someone says it's illegal for you to program your own CPAP machine, doesn't make it true. It sounds thin and it is. Ok. I actually don't know, but I was willing to risk a little civil disobedience, and frankly, I don't care about the law, it's my health. Maybe it is illegal for a tech to provide instructions?
  3. The electronic world has opened a tremendous set of resources for self-care. If you are a quick learner, and especially if you are willing to apply a little engineering thought and self-experimentation, in some cases you can far outdo medical professionals. In my case, I suspect the doctor was not up to date on the newer APAP technology, and perhaps was not willing to take the time to fine-tune my results beyond the minimum acceptable.

(1) I took the Respironics Dreamstation back to the store and worked a little with the tech, who was not happy with me. When I hooked up the machine and tried to show her how much noise it was making, she was not at all impressed. Nor was I. It had been MUCH louder previously. It turns out the machine has a water reservoir on it if you want to use the humidifier feature. But if you don't, you can take it off. It makes the machine more compact, and that is how I had used my previous machine. Unfortunately, it turns out that the reservoir provides sound buffering, even more so when there's water in it. So once I took off the reservoir container, it was loud again. She switched me to the other machine.