Ok, so a couple of more views.
<b>
1. About CAB vs Coupe.</b>
Jeff said, and I think others chimed in, that Cabs sell for 10-20% more. Well I sure would like to see the data on that. In any case, this sample of cars-for-sale does not support that claim. The data from this sample clearly indicates that both cabs and coupes are equal in value. I updated the one chart (here) using a power curve trendline to see if it adds some clarity, but the results are the same.
Statistically in this sample:
- Cabs: 24, average sale price: $15,374
- Coupes: 11, average sale price: $15,550
<b>
2. About tips vs manual transmission</b>
I went through the listings and captured that information in the data.
Statistically in this sample:
- Tips: 16, average sale price: $15,715
- Manual: 19, average sale price: $15,189
Here is a visual on tips vs manual. Most likely we would conclude there is no difference between tip vs manual, with small price advantage for tips on average, but slight advantage for manuals in the high price range.
<b>So.... now where does that leave us? (need help here)</b>
- first point must be to question is this sample is truly representative of "all 968 sales". I am not sure how to answer that question, but it is a valid one, since so many experienced forum members claim that cabs are more valuable than coupes, and manuals are more valuable than tips. We probably need more data to confirm one way or the other. In the absence of other data, given the recent state of this sample, we might want to consider it more representative than people's memory or intuition from the past.
- I have a theory why tip cars are not lower in price. The reason is that many may be in better condition than a peer 968 with a manual transmission. Let's assume our intuition is right, the tip cars may be owned by people who are: gentle drivers, occasional drivers, do not track their car, do not install performance enhancements, etc. The result may actually be a car that is less worn and generally in better condition that a comparable 968 with a manual transmission. So, on the other hand, we can argue that this is an unfair correlation between condition of the car and the presence of the tip, but at some level the data may make it obvious that a "tip car" is no less valuable than a manual transmission car (at least in this sample).
Other comments or interpretations?
Roland
updated sheet for inspection: