In the past, only successfully completed repairs were included in our analysis of responses to the Car Reliability Survey. This was done to provide the most precise results possible given our often small sample sizes. Problem was, this excluded the worst problems–those that lead a person to get rid of a car–from the analysis. So, starting with this month’s survey,… More →
Category: Research Methods
Research Methods
Changes to the Car Reliability Survey
Entering the second quarter of 2009, we’ve made three changes to the Car Reliability Survey. First, major preventative maintenance, most notably timing belts and water pumps, now should be reported on the repair survey. This change has been made to equalize results between engines with timing belts and those with timing chains. Those with timing chains generally cost less to… More →
#1 threat: spam filters
Nothing provides more challenges for TrueDelta’s Car Reliability Survey than email, specifically getting it to the inboxes of people who’ve signed up to participate. Too often, it gets trapped by a “bulk” or spam filter. Some filters are better than others. The worst routinely identify TrueDelta’s email as spam, even though we send no spam and are on no blacklists.… More →
No, we’re not expecting multiple responses each month
I’m recently learned that some members think we expect multiple responses to the Car Reliability Survey each month, so they haven’t been responding. Apparently, things have gotten twisted entirely around. Hopefully this post will help untwist them. The reason for the misperception: these members have been receiving three or four emails each month that say, “Response needed even if there… More →
Water pumps and timing belt tensioners
I’ve written before about timing belts vs. timing chains. I strongly prefer the latter, because they don’t have to be replaced every 60,000 to 100,000 miles at a cost of 300 to 600 dollars (nearly all of it labor). But TrueDelta’s repair rate analysis has disadvantaged engines with timing chains. Because most of the cost of replacing a timing belt… More →
January challenge
After noting the dates of the Chicago Auto Show, I realized that the February results will have to be released on the 5th to avoid that media frenzy. Which will be tough, since the current survey won’t end until late at night on the 2nd. Actually, it’s even worse. The press release firm we use requires a two-day lead time.… More →
Ball fumbled just short of the goal line–will anyone pick it up?
Every January, April, July, and October I closely watch the responses as they come in, a flood the first couple of days, a trickle towards the end. How many people will respond this time? Well, for October 2008 (which technically ends tomorrow morning), a bit over 7,700, up from a bit over 7,000 last time. The response rate this time: 35.4… More →
Crunch time for the August results
We start each round of surveys on the first Tuesday of the month. So a few days remain to gather responses for the August results, which will cover members’ repair experiences through the end of June. This has been a difficult month. Response rates have been down compared to previous quarters. Just a few percentage points, but that represents hundreds… More →
A UK vehicle reliability survey
This morning I received an email from Britain’s Auto Express magazine, announcing that the results to “Britain’s top car reliability survey” had been posted here. Intrigued, I clicked through to check it out, and found that some European models do quite well. At the model level, the top four are the Skoda Octavia (related to the VW Jetta), Land Rover Discovery… More →
Tweaks to the repair survey
Starting this month, I’ve added a new outcome to the repair survey: successful repair without replacing parts. I’ve done this because a small but not insignificant portion of repairs involve cleaning, lubricating, adjusting, or otherwise improving the function of a part rather than replacing this part. Months ago I wondered whether these should be considered repairs. I’m still not sure.… More →