<story><title>I’m trying to understand hedonic adjustments</title><url>https://www.epsilontheory.com/im-trying-to-understand-hedonic-adjustments/</url></story><parent_chain></parent_chain><comment><author>dragonwriter</author><text>So, the author is trying to understand hedonic adjustment, and does it via the BLS CPI series for new car purchases.&lt;p&gt;Which is rather clearly a fatal error since BLS uses cost-based, rather than hedonic, quality adjustments for new car and truck purchases. [0] The author is trying to understand a process by examining an area in which the process is not applied.&lt;p&gt;[0] &lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;www.bls.gov&amp;#x2F;cpi&amp;#x2F;quality-adjustment&amp;#x2F;&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;www.bls.gov&amp;#x2F;cpi&amp;#x2F;quality-adjustment&amp;#x2F;&lt;/a&gt; (see ELI TA011)</text></comment>
<story><title>I’m trying to understand hedonic adjustments</title><url>https://www.epsilontheory.com/im-trying-to-understand-hedonic-adjustments/</url></story><parent_chain></parent_chain><comment><author>biren34</author><text>I work with data a lot, and my main issue with hedonic adjustment is that anytime I&amp;#x27;ve ever made any such adjustment to &amp;quot;improve&amp;quot; a metric that wasn&amp;#x27;t purely mechanical (like a moving average or a ratio to another number), it&amp;#x27;s just one step away from making the number say &lt;i&gt;anything&lt;/i&gt; I want it to.&lt;p&gt;The entire concept of &amp;quot;fixing&amp;quot; a metric relies on an inhuman level of self-truthfulness to not just lead you down the path of hearing only what you want to hear.&lt;p&gt;The point of metrics is that they should slap you in the face with objective reality, and improvement is just too subjective a concept.</text></comment>