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This doesn't show that biking has gotten safer. It may have, but later adopters of biking are also less likely to engage in risky behavior. Similarly, as the p

This doesn't show that biking has gotten safer. It may have, but later adopters of biking are also less likely to engage in risky behavior. Similarly, as the percentage of folks who use heroin increases, the relative rate of overdoses declines. But that doesn't mean that heroin itself has become any more or less safe.

nowarninglabel 9y ago
I don't know, I mean surely there are some network effects of the more users that are using heroin the more that safe practices are developed, shared, and (socially) enforced. It'd be interesting to see if anyone has studied that. Granted, a counter-argument might be that even if it were safer from greater use it may just be that greater use nearly always leads to greater regulation.
emh68 9y ago
What's missing from the heroin analogy is fact that the dangers faced by cyclists can be changed - if drivers see a cyclist every 5 minutes vs every 1 hour, they'll be looking out for bicyclists constantly.
- CydeWeys 9y ago
  What's also missing from the heroin analogy is that heroin itself is becoming safer as its use becomes widespread. It's made to a higher quality, with more standardized production processes, people know how to measure strength better, and the average person becomes more likely to know a good source for safe heroin that isn't cut with dangerous drugs like fentanyl. Take it to the logical extreme, imagining legalization of heroin and subsequent widespread use and sale in convenience stores, and it'd be way safer, because you'd always be getting a standardized product.
  - Alex3917 9y ago
    > heroin itself is becoming safer as its use becomes widespread That definitely was true for a while, not sure about in the last few years. A less controversial analogy might be with coffee, where the rate of people overdosing is probably lower now that it's no longer mainly used by Sufi mystics in enormous doses for entheogenic purposes.
lkbm 9y ago
That's a really good alternate hypothesis to explain the correlation--and one I hadn't thought of. The best way I can think to reject the risk-aversion hypothesis (without doing a RCT) would be to see a time-lag. If accident rates drop after ridership increases, that would suggest it's not risk-adverse people coming in later, whereas if ridership increases lead the rate drop, that would indicate that it's not a risk-tolerance thing. On the other hand, ridership increase proceeding accident rate dropping might need to account for newer riders being less experienced. I've read/read about other studies that found the same thing as this one, but I'm having trouble finding them right now. I found [0], but the methodology doesn't look like it would address the risk-aversion hypothesis. Personally, I think we should encourage cycling even if it doesn't lower accident rates, but evidence of improved safety makes it a more rational choice for urban planners. [0] https://www.washingtonpost.com/news/wonk/wp/2014/04/17/actually-cyclists-make-city-streets-safer/ https://www.washingtonpost.com/news/wonk/wp/2014/04/17/actua...
tmnvix 9y ago
I take your point, but if we are going to measure how likely it is for an activity to lead to death then total deaths and total participants (or 'participant-time') are what we will look at. Most people would agree that driving has become a safer activity if you could show them that the number of injuries or fatalities per driver or distance travelled has been falling. The same is true for cycling.
mpweiher 9y ago
You are assuming that the only/deciding factor is the behavior of the cyclists. For heroin, this is probably true, for cycling not so much.
- Alex3917 9y ago
  > You are assuming that the only/deciding factor is the behavior of the cyclists. I'm really not. Read what I actually wrote instead of projecting onto it.
  - mpweiher 9y ago
    "but later adopters of biking are also less likely to engage in risky behavior."
    - lkbm 9y ago
      Saying "x is a factor" is not the same thing as saying "only x is a factor".
      - mpweiher 9y ago
        Yeah, but saying this factor is the reason the other factors don't matter means it is the deciding factor.
        Alex3917 9y ago
        I didn't say the other factors didn't matter, or even that the theory in the article was incorrect. I was just saying that the statistical analysis in the article isn't enough to prove the explanation offered.

nowarninglabel 9y ago

I don't know, I mean surely there are some network effects of the more users that are using heroin the more that safe practices are developed, shared, and (socially) enforced. It'd be interesting to see if anyone has studied that. Granted, a counter-argument might be that even if it were safer from greater use it may just be that greater use nearly always leads to greater regulation.

emh68 9y ago

What's missing from the heroin analogy is fact that the dangers faced by cyclists can be changed - if drivers see a cyclist every 5 minutes vs every 1 hour, they'll be looking out for bicyclists constantly.

CydeWeys 9y ago
What's also missing from the heroin analogy is that heroin itself is becoming safer as its use becomes widespread. It's made to a higher quality, with more standardized production processes, people know how to measure strength better, and the average person becomes more likely to know a good source for safe heroin that isn't cut with dangerous drugs like fentanyl. Take it to the logical extreme, imagining legalization of heroin and subsequent widespread use and sale in convenience stores, and it'd be way safer, because you'd always be getting a standardized product.
- Alex3917 9y ago
  > heroin itself is becoming safer as its use becomes widespread That definitely was true for a while, not sure about in the last few years. A less controversial analogy might be with coffee, where the rate of people overdosing is probably lower now that it's no longer mainly used by Sufi mystics in enormous doses for entheogenic purposes.

lkbm 9y ago

That's a really good alternate hypothesis to explain the correlation--and one I hadn't thought of. The best way I can think to reject the risk-aversion hypothesis (without doing a RCT) would be to see a time-lag. If accident rates drop after ridership increases, that would suggest it's not risk-adverse people coming in later, whereas if ridership increases lead the rate drop, that would indicate that it's not a risk-tolerance thing. On the other hand, ridership increase proceeding accident rate dropping might need to account for newer riders being less experienced. I've read/read about other studies that found the same thing as this one, but I'm having trouble finding them right now. I found [0], but the methodology doesn't look like it would address the risk-aversion hypothesis. Personally, I think we should encourage cycling even if it doesn't lower accident rates, but evidence of improved safety makes it a more rational choice for urban planners. [0] https://www.washingtonpost.com/news/wonk/wp/2014/04/17/actually-cyclists-make-city-streets-safer/ https://www.washingtonpost.com/news/wonk/wp/2014/04/17/actua...

tmnvix 9y ago

I take your point, but if we are going to measure how likely it is for an activity to lead to death then total deaths and total participants (or 'participant-time') are what we will look at. Most people would agree that driving has become a safer activity if you could show them that the number of injuries or fatalities per driver or distance travelled has been falling. The same is true for cycling.

mpweiher 9y ago

You are assuming that the only/deciding factor is the behavior of the cyclists. For heroin, this is probably true, for cycling not so much.

Alex3917 9y ago
> You are assuming that the only/deciding factor is the behavior of the cyclists. I'm really not. Read what I actually wrote instead of projecting onto it.
- mpweiher 9y ago
  "but later adopters of biking are also less likely to engage in risky behavior."
  - lkbm 9y ago
    Saying "x is a factor" is not the same thing as saying "only x is a factor".
    - mpweiher 9y ago
      Yeah, but saying this factor is the reason the other factors don't matter means it is the deciding factor.
      - Alex3917 9y ago
        I didn't say the other factors didn't matter, or even that the theory in the article was incorrect. I was just saying that the statistical analysis in the article isn't enough to prove the explanation offered.