znod

Well, I'm not sure the question was ever really stated - at least not in this thread. Regardless, I'd argue that reliability is nothing by itself - it's only a representation of other things. When talking about automobiles, reliability is nothing more than a metric - a loose measure (sometimes a guesstimate based on reputation) used to forecast the frequency that your car may break down (the occurence of one or more threats that could cause this to happen). So risk is core to the discussion. Your car is at risk for alternator failure in very hot weather. The threat is that it will break, causing you to be stranded. If this happens, you may decide that brand x's alternators are not very good, or unreliable.

Tires are a source of break downs. We carry spares and join the auto club. In more recent years, we've come to rely on assistance dispatched via telematics and the use of runflats so we can keep moving. Heck, you can even purchase insurance for your tires in case you hit something and damage them. The argument that calls for absolute reliability is like asking for tires that will never fail. It's unrealistic and unfair to demand.
[/quote]
I think he did ask What makes a car reliable and gave his own opinions. As I said we all have different views on this and I accept your points as well.
[/quote]


Sure. I'm not blind - I do accept and agree that this is one way to interpret reliability. However, I feel the definition given would be absolute reliability, and argued many points around risk, threats, reliability, etc... Unfortunately, I did not articulate the logic behind my statements.


Here goes...

If we can all agree that it is reasonable to expect failure in components - be it tires, alternators, etc... then why not some amount of repairs for a car? All cars -do- need them. I think we're quibbling over single digit percentages - deltas between marques that are either imaginary, or small enough that they are statistically insignificant (read Freakonomics for more on statistically unfounded or insignificant things getting too much public attention). Every car -will- break down. Talking about absolute perfection - zero repairs - is well... not grounded in reality. Please forgive my inability to overlook this.

If we can accept that all cars will need repairs, then the only step or remedy is to mitigate risk. It would be nice to have ironclad perfection that never ever broke, but it's simply not realistic. Get ironclad warranty coverage and be done with it.
[/quote]

A BRIEF THEORY OF AUTO RELIABILITY AND ITS DECISION CONSEQUENCES


Before I give the theory I want to mention that ipse d just gave the starting points for his concepts of "scales" of (1) auto reliability and (2) cost of auto unreliability. Below, in quotes, is what he said with my comments juxtaposed in orange. In this regard, he did not attempt to define auto reliability nor did he attempt to define cost of auto unreliability.

"Reliability, for me, is 'free of problems'". This statement defines his auto-reliability scale's natural zero point--where a car does not break period.

"Reliability, for me, is not 'free cost of repair to fix problems'". This statement defines his costs-of-auto-unreliablity scale's natural zero point--where a car generates no breakage costs.

Consideration of these two scale concepts provides the basis for the "theory." They are implicit in my post #7 replies. And, the theory also is based on UUronl's addition ofr risk to our discussion of auto reliability.

Two factors need to be considered when when talking about risky things--the probability distribution of the phenomenon of interest (which is individualized) and the individual's attitude towards towards the distribution. For example, consider the probability distributions of the returns from portfolios of securities. One measure related to such a distribution is its expected return. If an individual is risk neutral, then he or she could rank portfolios in terms of desirability on the basis of their expected returns. However, most individuals are risk averse and, thus, ranking on expected returns is not appropriate. Such individuals will value sequential increases in equal amounts of expected return less and less as portfolio risk (which is individualized) becomes larger and larger. This framework applies precisely to reliability, althought I won't flesh it out even as much as above.

(1) There is the individual's probaility distruibution for the monetary consequences of a car breaking. One's attitude towards that distribution governs the amount of risk he or she is willing to accept. If the risk of a large negative total monetary outcome is too large, then he or she will buy a different car or will insure by purchasing an extended warranty.

(2) On the other hand, there is the individual's probability distribution for the inconvenience of a car breaking. In this case, if the risk of a car breaking too frequently is too large, then he or she will buy a different car.

When deciding on a car, "rational" individuals will consider both types of probability distributions implicitly and will somehow muddle through to a decision. Under this view, the breakage probability distributions for the different things that can break on a car provide measures of it reliability for the type of "breakings" being considered. In this regard, it would be meaningless to talk about the overall reliability of a car unless the breakages of different magnitudes were consider to be equal or some sort of arbitrary weighting scheme was applied to the different types of breakage. Meaning comes only when one attaches monetary consequences (and realted probabilities) as discussed under (1) above to the possible breakages and attaches inconvenience consequences (and related probabilities) as discussed under (2) above to the possible breakages.

Please comment. I dreamed the theory up quickly, and I'll go back and revise as you change my mind about what I dreamed.
[/quote]


I find it interesting to see another industry's perspective on risk, etc...


I would suggest three categories of consideration - cost, inconvenience, safety

That's a good idea. It could be added to the theory just like (1) and (2). The factors are probability distributions for the monetary costs of breakage that results in injury to oneself or others and one's related distributional preferences.

I still don't like the use of the word reliability, but I think breakage and defects are interchangeable.


I think in addition to cost, meaning can be assigned in the manner I lay out earlier - in terms of immobilizing and non-immobilizing. These designations are clear and unambiguous, and would carry some amount of implied inconvenience and safety consequences.

I think it would be the other way around inconvenience would be implied by either immobilizing or non-immobilizing breakage. There is more to the incovenience dimension than the dichotomy you mention. For example, there is the time at the dealer whether the breakage is immobilizing or non-immobilizing.

There is yet another unmentioned aspect. There should be a factor representing the propensity of the owner to have small repairs performed. Not all owners will react the same way to defects (some may not even notice certain defects... rattles+deaf=non-issue) Take me for example. I have the "High Battery Drain" message, some squeaks and rattles, and the dealer owes me two interior trim pieces. It has been nearly 9 months since I purchased the car, yet I'm not willing to take it in for these minor defects. Some owners drop the car off when the slightest issue arises. There must be some way to characterize this sort of variance in behavior. I think maybe it makes sense to apply a separate factor for each of the three categories (which would provide some form of individualized value characterization). I don't have children, so my factor for safety-related defects might not be as high as someone's whose passengers are small children. (Remember, I'm the guy whose boss yelled at him to stop riding around on his skinny spare tire on a previous car - it had been months)

In the theory, what you mention is captured by the individuals attitudes toward the inconvenience probability distributions--i.e., some breakages would not be considered to be inconvenience inducing.


Anyway, good idea. Good thread.

Yep, fun. I wonder what happened to ipse d.
[/quote]

ipse dixit

Well, I'm not sure the question was ever really stated - at least not in this thread. Regardless, I'd argue that reliability is nothing by itself - it's only a representation of other things. When talking about automobiles, reliability is nothing more than a metric - a loose measure (sometimes a guesstimate based on reputation) used to forecast the frequency that your car may break down (the occurence of one or more threats that could cause this to happen). So risk is core to the discussion. Your car is at risk for alternator failure in very hot weather. The threat is that it will break, causing you to be stranded. If this happens, you may decide that brand x's alternators are not very good, or unreliable.

Tires are a source of break downs. We carry spares and join the auto club. In more recent years, we've come to rely on assistance dispatched via telematics and the use of runflats so we can keep moving. Heck, you can even purchase insurance for your tires in case you hit something and damage them. The argument that calls for absolute reliability is like asking for tires that will never fail. It's unrealistic and unfair to demand.
[/quote]
I think he did ask What makes a car reliable and gave his own opinions. As I said we all have different views on this and I accept your points as well.
[/quote]


Sure. I'm not blind - I do accept and agree that this is one way to interpret reliability. However, I feel the definition given would be absolute reliability, and argued many points around risk, threats, reliability, etc... Unfortunately, I did not articulate the logic behind my statements.


Here goes...

If we can all agree that it is reasonable to expect failure in components - be it tires, alternators, etc... then why not some amount of repairs for a car? All cars -do- need them. I think we're quibbling over single digit percentages - deltas between marques that are either imaginary, or small enough that they are statistically insignificant (read Freakonomics for more on statistically unfounded or insignificant things getting too much public attention). Every car -will- break down. Talking about absolute perfection - zero repairs - is well... not grounded in reality. Please forgive my inability to overlook this.

If we can accept that all cars will need repairs, then the only step or remedy is to mitigate risk. It would be nice to have ironclad perfection that never ever broke, but it's simply not realistic. Get ironclad warranty coverage and be done with it.
[/quote]

A BRIEF THEORY OF AUTO RELIABILITY AND ITS DECISION CONSEQUENCES

Before I give the theory I want to mention that ipse d just gave the starting points for his concepts of "scales" of (1) auto reliability and (2) cost of auto unreliability. Below, in quotes, is what he said with my comments juxtaposed in orange. In this regard, he did not attempt to define auto reliability nor did he attempt to define cost of auto unreliability.

"Reliability, for me, is 'free of problems'". This statement defines his auto-reliability scale's natural zero point--where a car does not break period.

"Reliability, for me, is not 'free cost of repair to fix problems'". This statement defines his costs-of-auto-unreliablity scale's natural zero point.

Consideration of these two scale concepts provides the basis for the "theory."

Two factors need to be considered when when talking about risky things--the probability distribution of the phenomenon of interest (which is individualized) and the individual's attitude towards towards the distribution. For example, consider the probability distributions of the returns from portfolios of securities. One measure related to such a distribution is its expected return. If an individual is risk neutral, then he or she could rank portfolios in terms of desirability on the basis of their expected returns. However, most individuals are risk averse and, thus, ranking on expected returns is not appropriate. Such individuals will value sequential increases in equal amounts of expected return less and less as portfolio risk (which is individualized) becomes larger and larger. This framework applies precisely to reliability, althought I won't flesh it out even as much as above.

(1) There is the individual's probaility distruibution for the monetary consequences of a car breaking. One's attitude towards that distribution governs the amount of risk he or she is willing to accept. If the risk of a large negative total monetary outcome is too large, then he or she will buy a different car or will insure by purchasing an extended warranty.

(2) On the other hand, there is the individual's probability distribution for the inconvenience of a car breaking. In this case, if the risk of a car breaking too frequently is too large, then he or she will buy a different car.

When deciding on a car, "rational" individuals will consider both types of probability distributions implicitly and will somehow muddle through to a decision. Under this view, the breakage probability distributions for the different things that can break on a car provide measures of it reliability for the type of "breakings" being considered. In this regard, it would be meaningless to talk about the overall reliability of a car unless the breakages of different magnitudes were consider to be equal or some sort of arbitrary weighting scheme was applied to the different types of breakage. Meaning comes only when one attaches monetary consequences (and realted probabilities) as discussed under (1) above to the possible breakages and attaches inconvenience consequences (and related probabilities) as discussed under (2) above to the possible breakages.

Please comment. I dreamed the theory up quickly, and I'll go back and revise as you change my mind about what I dreamed.
[/quote]


I find it interesting to see another industry's perspective on risk, etc...


I would suggest three categories of consideration - cost, inconvenience, safety

That's a good idea. It could be added to the theory just like (1) and (2). The factors are probability distributions for the monetary costs of breakage that results in injury to oneself or others and one's related distributional preferences.

I still don't like the use of the word reliability, but I think breakage and defects are interchangeable.


I think in addition to cost, meaning can be assigned in the manner I lay out earlier - in terms of immobilizing and non-immobilizing. These designations are clear and unambiguous, and would carry some amount of implied inconvenience and safety consequences.

I think it would be the other way around inconvenience would be implied by either immobilizing or non-immobilizing breakage. There is more to the incovenience dimension than the dichotomy you mention. For example, there is the time at the dealer whether the breakage is immobilizing or non-immobilizing.

There is yet another unmentioned aspect. There should be a factor representing the propensity of the owner to have small repairs performed. Not all owners will react the same way to defects (some may not even notice certain defects... rattles+deaf=non-issue) Take me for example. I have the "High Battery Drain" message, some squeaks and rattles, and the dealer owes me two interior trim pieces. It has been nearly 9 months since I purchased the car, yet I'm not willing to take it in for these minor defects. Some owners drop the car off when the slightest issue arises. There must be some way to characterize this sort of variance in behavior. I think maybe it makes sense to apply a separate factor for each of the three categories (which would provide some form of individualized value characterization). I don't have children, so my factor for safety-related defects might not be as high as someone's whose passengers are small children. (Remember, I'm the guy whose boss yelled at him to stop riding around on his skinny spare tire on a previous car - it had been months)

In the theory, what you mention is captured by the individuals attitudes toward the inconvenience probability distributions--i.e., some breakages would not be considered to be inconvenience inducing.


Anyway, good idea. Good thread.

Yep, fun. I wonder what happened to ipse d.
[/quote]
[/quote]

Goodness. You guys are much too erudite for me.

All I was trying to do was make a simple point about warranties and reliability -- i.e., that one does not necessarily follow the other.

You guys have taken that point of discussion to another stratosphere.

It's like beginning with the proposition that the "Earth is not flat" and having it evolve into the "Universe is composed of unexplained dark matter ..."

I'm simply not worthy.

cobradav

Hey, that's what we're here for, take an idea and expaaaaaaaand on it. You know you out

znod

Well, I'm not sure the question was ever really stated - at least not in this thread. Regardless, I'd argue that reliability is nothing by itself - it's only a representation of other things. When talking about automobiles, reliability is nothing more than a metric - a loose measure (sometimes a guesstimate based on reputation) used to forecast the frequency that your car may break down (the occurence of one or more threats that could cause this to happen). So risk is core to the discussion. Your car is at risk for alternator failure in very hot weather. The threat is that it will break, causing you to be stranded. If this happens, you may decide that brand x's alternators are not very good, or unreliable.

Tires are a source of break downs. We carry spares and join the auto club. In more recent years, we've come to rely on assistance dispatched via telematics and the use of runflats so we can keep moving. Heck, you can even purchase insurance for your tires in case you hit something and damage them. The argument that calls for absolute reliability is like asking for tires that will never fail. It's unrealistic and unfair to demand.
[/quote]
I think he did ask What makes a car reliable and gave his own opinions. As I said we all have different views on this and I accept your points as well.
[/quote]


Sure. I'm not blind - I do accept and agree that this is one way to interpret reliability. However, I feel the definition given would be absolute reliability, and argued many points around risk, threats, reliability, etc... Unfortunately, I did not articulate the logic behind my statements.


Here goes...

If we can all agree that it is reasonable to expect failure in components - be it tires, alternators, etc... then why not some amount of repairs for a car? All cars -do- need them. I think we're quibbling over single digit percentages - deltas between marques that are either imaginary, or small enough that they are statistically insignificant (read Freakonomics for more on statistically unfounded or insignificant things getting too much public attention). Every car -will- break down. Talking about absolute perfection - zero repairs - is well... not grounded in reality. Please forgive my inability to overlook this.

If we can accept that all cars will need repairs, then the only step or remedy is to mitigate risk. It would be nice to have ironclad perfection that never ever broke, but it's simply not realistic. Get ironclad warranty coverage and be done with it.
[/quote]

A BRIEF THEORY OF AUTO RELIABILITY AND ITS DECISION CONSEQUENCES


Before I give the theory I want to mention that ipse d just gave the starting points for his concepts of "scales" of (1) auto reliability and (2) cost of auto unreliability. Below, in quotes, is what he said with my comments juxtaposed in orange. In this regard, he did not attempt to define auto reliability nor did he attempt to define cost of auto unreliability.

"Reliability, for me, is 'free of problems'". This statement defines his auto-reliability scale's natural zero point--where a car does not break period.

"Reliability, for me, is not 'free cost of repair to fix problems'". This statement defines his costs-of-auto-unreliablity scale's natural zero point--where a car generates no breakage costs.

Consideration of these two scale concepts provides the basis for the "theory." They are implicit in my post #7 replies. And, the theory also is based on UUronl's addition ofr risk to our discussion of auto reliability.

Two factors need to be considered when when talking about risky things--the probability distribution of the phenomenon of interest (which is individualized) and the individual's attitude towards towards the distribution. For example, consider the probability distributions of the returns from portfolios of securities. One measure related to such a distribution is its expected return. If an individual is risk neutral, then he or she could rank portfolios in terms of desirability on the basis of their expected returns. However, most individuals are risk averse and, thus, ranking on expected returns is not appropriate. Such individuals will value sequential increases in equal amounts of expected return less and less as portfolio risk (which is individualized) becomes larger and larger. This framework applies precisely to reliability, althought I won't flesh it out even as much as above.

(1) There is the individual's probaility distruibution for the monetary consequences of a car breaking. One's attitude towards that distribution governs the amount of risk he or she is willing to accept. If the risk of a large negative total monetary outcome is too large, then he or she will buy a different car or will insure by purchasing an extended warranty.

(2) On the other hand, there is the individual's probability distribution for the inconvenience of a car breaking. In this case, if the risk of a car breaking too frequently is too large, then he or she will buy a different car.

When deciding on a car, "rational" individuals will consider both types of probability distributions implicitly and will somehow muddle through to a decision. Under this view, the breakage probability distributions for the different things that can break on a car provide measures of it reliability for the type of "breakings" being considered. In this regard, it would be meaningless to talk about the overall reliability of a car unless the breakages of different magnitudes were consider to be equal or some sort of arbitrary weighting scheme was applied to the different types of breakage. Meaning comes only when one attaches monetary consequences (and realted probabilities) as discussed under (1) above to the possible breakages and attaches inconvenience consequences (and related probabilities) as discussed under (2) above to the possible breakages.

Please comment. I dreamed the theory up quickly, and I'll go back and revise as you change my mind about what I dreamed.
[/quote]


I find it interesting to see another industry's perspective on risk, etc...


I would suggest three categories of consideration - cost, inconvenience, safety

That's a good idea. It could be added to the theory just like (1) and (2). The factors are probability distributions for the monetary costs of breakage that results in injury to oneself or others and one's related distributional preferences.

I still don't like the use of the word reliability, but I think breakage and defects are interchangeable.


I think in addition to cost, meaning can be assigned in the manner I lay out earlier - in terms of immobilizing and non-immobilizing. These designations are clear and unambiguous, and would carry some amount of implied inconvenience and safety consequences.

I think it would be the other way around inconvenience would be implied by either immobilizing or non-immobilizing breakage. There is more to the incovenience dimension than the dichotomy you mention. For example, there is the time at the dealer whether the breakage is immobilizing or non-immobilizing.

There is yet another unmentioned aspect. There should be a factor representing the propensity of the owner to have small repairs performed. Not all owners will react the same way to defects (some may not even notice certain defects... rattles+deaf=non-issue) Take me for example. I have the "High Battery Drain" message, some squeaks and rattles, and the dealer owes me two interior trim pieces. It has been nearly 9 months since I purchased the car, yet I'm not willing to take it in for these minor defects. Some owners drop the car off when the slightest issue arises. There must be some way to characterize this sort of variance in behavior. I think maybe it makes sense to apply a separate factor for each of the three categories (which would provide some form of individualized value characterization). I don't have children, so my factor for safety-related defects might not be as high as someone's whose passengers are small children. (Remember, I'm the guy whose boss yelled at him to stop riding around on his skinny spare tire on a previous car - it had been months)

In the theory, what you mention is captured by the individuals attitudes toward the inconvenience probability distributions--i.e., some breakages would not be considered to be inconvenience inducing.


Anyway, good idea. Good thread.

Yep, fun. I wonder what happened to ipse d.
[/quote]
[/quote]

Goodness. You guys are much too erudite for me.

All I was trying to do was make a simple point about warranties and reliability -- i.e., that one does not necessarily follow the other.

You guys have taken that point of discussion to another stratosphere.

It's like beginning with the proposition that the "Earth is not flat" and having it evolve into the "Universe is composed of unexplained dark matter ..."

I'm simply not worthy.
[/quote]
We just didn't want your highly worthy start to fall into the black hole of undevelopness. Your effort was seminal, and, thus, you get most of the credit (or blame ). How was Phoenix, and where did you eat? Was the trip successful?

I looked back at your relpy to "the" theory and noted that you must of been posting while I was editing. Note that I gave you "credit" for its develpment too. I fixed all of the post where mention of you was left out. I know you really don't care, but you were the one bringing risk into the discussion.

UUronL

Thanks, and you're right - I don't require any sort of recognition, but thank you anyway.


I think I was trying to say the same thing regarding inconvenience, that it was implied already if your car was immobile. Same for safety, there is an implied danger to your person when your car breaks down.

I also agree that there is an amount of inconvenience to which I did not grant treatment. Certainly the inconvenience of taking the car into the shop, and also the inconvenience of living with an unrepaired defect. That cost-benefit exercise also must be squeezed in there someplace.

znod

Thanks, and you're right - I don't require any sort of recognition, but thank you anyway.


I think I was trying to say the same thing regarding inconvenience, that it was implied already if your car was immobile. Same for safety, there is an implied danger to your person when your car breaks down.

I also agree that there is an amount of inconvenience to which I did not grant treatment. Certainly the inconvenience of taking the car into the shop, and also the inconvenience of living with an unrepaired defect. That cost-benefit exercise also must be squeezed in there someplace.
[/quote]
The cost benefit tradeoffs are implicit in the model. Either taking to the shop or living with a defect would be the inconvenience factor for the defect/breakage--depending what action the indiviudal would take given the defect/breakage. That is, the action the indivdual chooses would determine the inconvenience factor for the defect/breakage.