I’m Trying To Understand Hedonic Adjustments

Brent Donnelly is a senior risk-taker and FX market maker at HSBC New York and has been trading fore
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  1. Another hedonic adjustment is how much more pleasurable life is in 2020 than it was in 1990.

  2. CPI is cost of living any time that making it such keeps the government from paying out more of our money to us. All other times it’s definitely not cost of living. Schrodinger’s CPI.

  3. The truth is what we need it to be —-and this , to me, is the biggest example of all. The real inflation rate cannot be known - the Government’s solvency rests on it.

    More and more missionary’s are speaking on the subject and it’s the thing that can bring the whole house of cards down.

    Of course they and their renfields in the media will blame the markets and capitalism for the crash and use the whole crisis to consolidate their power. Our road to serfdom will then be complete.

  4. First question: who benefits from CPI as measured? Second question: who benefits from CPI being under reported? Third question: which societal group has had their share of national income under structural pressure over the post Volker years?

  5. Wouldn’t evenly applied hedonic quality adjustments increase the adjusted ‘cost’ of goods which get worse in quality? I’ve never heard that flow rate limiting shower nozzles which cost the same dollar value as good shower nozzles had a huge upward hedonic ‘cost’ adjustment.

    Ditto for paper-thin jeans, un-flushable toilets, clothes dryers you have to run three times per load, bloatware-encrusted cheap computers, the thing in cars that beeps at you when it’s angry…

    Rather than accept the entire premise and argue with the implementation, I’m going to reject the premise that hedonic quality adjustments are a valid way of measuring constant standard of living. Fortunately, there’s an even simpler reason why we can reject the entire concept. If you assume that overall happiness remains constant across this period of hedonic growth, there’s no reason why we should accept a downwards ‘cost’ adjustment.

    Happiness associated with material goods is largely zero-sum. Humans look to those around them for cues about how valuable our possessions are. It doesn’t really matter to my day-to-day life that I live better than Louis XVI if my neighbor gets a new car and I’m still driving my college POS.

    Furthermore, we still have to pay the prices out of our pocket. Additionally, as one gentleman memorably put it a few years ago, “we can’t eat iPads!”.

    Accepting this simplifies things a lot. Ignore the hedonic adjustments, just do an apples to apples comparison. I’d suggest percent of median income; real income runs into problems if CPI is incorrect. Lets call this new measure subjective inflation and see what it tells us.

  6. I always thought that would make a great thesis for some graduate student.

  7. My God is this just beautifully written and 100% correct.

  8. An under-appreciated issue here is how CPI must be rigged to damp feedback effects. When payments are indexed to inflation metrics (such as social security and union rates), and good/service costs are indexed to inflation expectations via consumer price increases and contractual rate adjustment schemes, you get a self-reinforcing feedback loop. Higher costs → higher income → higher costs. Accurate inflation-measuring combined with automatic contract indexing makes the system dynamically unstable from a control-theory standpoint. It is thus mechanically necessary for system stability that either the inflation adjustments don’t fully compensate for measured inflation, or the inflation metric systematically under-reports real inflation.

    Everybody seems to have forgotten the CPI system was DESIGNED to under-report cost of living inflation.

  9. Avatar for MJ304 MJ304 says:

    Is that after adjustment for COVID? :wink:

  10. Avatar for Pat_W Pat_W says:


  11. Avatar for Pat_W Pat_W says:

    In Latin America all countries I am aware of simply tract a basic “basket of goods” for a family of 4. This includes X quantities of rice, beans, powdered milk, salt, and a few other things. they track the things that matter to people then compare increases in prices month by month and year by year.

    Other commentators pegged the actual intent o the VPI very well. It’s purpose is to keep the U.S government solvent.

  12. To be fair, being old enough to remember my families 1974 Chevy Nova that had its front passenger floorboard rust out to allow direct street ventilation, at less than 60k miles BTW, things do improve and some sort of adjustment is necessary. Does making these adjustments cause other distortions? Sure. But not doing them at all isn’t helpful either. Here is a quote from a recent article, which discusses the “aging American car fleet” which only happens because cars today are much better.

    “In the mid-’90s, 100,000 miles was about all you would get out of a vehicle. Now, at a 100,000 miles a vehicle is just getting broken in,” said IHS Markit’s Todd Campau.


    Another thing to consider. When you dated a girl in the 1970s you knew she was interested in a long term relationship if she had her data “work on the car together”. The dad wanted to know if a future son in law could do basic auto maintenance, which would include changing tires, changing oil and lube, changing spark plugs and point, along with timing the ignition, cleaning and adjusting carbonators, etc. Because if you couldn’t do these things, he knew he would be drafted to do such things. Not only are some of these things not even on cars anymore, spark plug changes occur once or twice in a car’s lifetime. Yes cars cost more, but maintenance is much easier too.

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