Aren’t “quality adjustments” by definition “hedonic adjustments”? How are these not hedonic adjustments? From the linked PDF:
“BLS adjusts for structural and engineering quality changes such as:
• Changes that affect the safety of occupants of the vehicle as mandated by legislated federal or state standards, and for purposes of IPP export items, applicable foreign market standards. Changes in safety features not required by legislated standards will be evaluated on a case-by-case basis.
• Changes in mechanical or electrical features that affect the overall operation or efficiency of the vehicle, or the ability of a component to perform its function, such as changes affecting steering, braking, stability, engine horsepower, traction control, transmission, battery life, and fuel systems and/or electrical systems.
• Changes in design or materials that affect the length of service, durability, need for repairs, or strength or performance of the item, such as stronger bumpers, HID headlamps, flexible body panels, platinum-tipped spark plugs, or warranty changes.
• Changes that affect comfort or convenience, if supported by evidence of a functional or software improvement, such as redesigned seat belts, remote door locks, theft deterrent systems, navigation and communication systems, satellite radio hardware, drive assist systems, backup cameras, sensors or changes in storage capacity.”