In a sense!
But not as a critique of smaller sample sizes—and in practice the population size isn’t ever relevant for surveys of the US, because there are ~zero surveys large enough to take this into account. (Even ACS.)
For statistical purposes you can treat the population of the US as infinite.
(But this doesn’t really matter for the population of the US until your sample size is in the tens of millions.)
Yes, but again because now you are sampling so many that you are starting to do some *counting*.
If you “sample” 490 of a population of 500, the statistical math is no longer the main thing you know.
For some questions you might want a more precise answer than this.
Or you might want information about smaller subpopulations—a sample size of 180 random Americans is plenty to tell you something about Americans as a whole, but not enough to tell you about Native American households specifically.
As an experiment, try a sample size of 180 with the population of the US *or* the population of Portland — the margin of error doesn’t change at all.
www.smartsurvey.co.uk/resources/ca...
Great. To be clear—180 would be perfectly usable sample size for these purposes.
It would give us 95% confidence that the median cash on hand was between ~$7,400 and $8,600.
bsky.app/profile/gend...
Do we?
It’s asking for population size not because you need a minimum percent but because if you are sampling a large enough fraction of a finite population you can rule out some distributions—you’re in effect starting to move from sampling to counting.
en.wikipedia.org/wiki/Margin_...
I have tried many ways of explaining that it is the absolute size of the sample, not the size of the sample relative to the population, that matters for our confidence in an estimate. For example, I point out that we could surely get a pretty accurate estimate of the probability of heads from a few thousand coin flips, even though the population is theoretically infinite. Whether judged by their skeptical looks or their answers to test questions, many students remain unconvinced by these arguments.
The size of the population is functionally irrelevant, but you’re not alone in finding this confusing!
www.tandfonline.com/doi/full/10....
Omelette
I know you don’t want to hear this, but—
There is in theory a citizen-initiated traffic violation enforcement process, although I’ve never heard of it being successfully used:
bikeportland.org/2015/06/09/d...
That said, we could have a usable app to notify city Parking Enforcement without legal changes—& we’ve successfully changed laws to facilitate enforcement before:
bikeportland.org/2022/02/17/b...
Thanks, Terry! Yeah, I assumed issuing tickets directly from public reports would take changing laws—will look through the code you linked.
In fairness I haven’t asked PBOT about any of this and assume there was some plausible operational reason for taking parking off of PDXReporter.
That said I’m confident we can do better than we are.
I am picking this issue up for the campaign. Other cities do it. We can, too.
3. Institute a system where illegal parking reports get a ticket mailed to the vehicle owner, like a traffic camera ticket.
This is a lot harder—requires legal changes, doesn’t cover all circumstances (brief stops in no-parking zones are allowed in some circumstances).
bsky.app/profile/brad...
Pdxreporter.org submission screen for pothole reporting
2. Reinstate a parking violation reporting app/portal.
Take a picture, confirm the location, click “submit.” We used to do this for parking, we still do it for potholes.
You get a confirmation email—so there’s a record you can refer to to document a recurring problem.
So: three levels of improvement, by increasing difficulty:
1. Make the phone number you call to report parking violations let you report parking violations.
No technical or legal changes needed, just have the city list a direct number to make reports.
bsky.app/profile/binn...
Will repeated parking violation reports in the same places shift enforcement priorities? Would they at some level get passed on to someone who could consider infrastructure changes (clearer signage, painted curbs)? Are they tracked in any way?
¯\_(ツ)_/¯
But assuming you successfully left a message with all the required information, including your own name—nothing happens.
Not just in the sense that the driver probably doesn’t get ticketed, but there’s no indication that the information will be used in any way.
Car parked in a crosswalk
Car parked in a crosswalk
The second menu level reads you a list of all the information needed to report a parking violation; the third level reads you the same information again and finally lets you leave a message.
At this point you have probably given up because you need to get your kid to school or whatever.
So you call the number and it sends you through three levels of recordings—the first of which asks you to press a number to hear information about reporting parking violations, *which is the thing you already called trying to do.*
Pdxreporter.org
Parking Enforcement is no longer accepting reports through PDX Reporter. To report an illegally parked vehicle, please call the PBOT Parking Enforcement hotline at 503-823-5195.
Portland has a convenient portal (pdxreporter.org) for reporting city maintenance problems, etc., with an option for reporting parking violations.
But—at some point it stopped letting you report parking violations, and directs you to a phone number.
Low-hanging fruit for Portland leaders would be to make reporting parking violations work, even a little bit. (Thread, I guess.)
I put on “A Love Supreme” this morning and my now 6-year-old kid threw a fist in the air and said “Yes! I love this music.”
Post Hidden by Muted Word
The word is “capitalism”.
Yeah there’s a serious anti-sea-lion constituency in Washington
www.seattletimes.com/seattle-news...
absolutely impossible to overstate how critical Jonathan’s elbow grease has been to the larger local transportation advocacy ecosystem over the past twenty years
I would probably vote for a ballot measure to throw all money raised under other ballot measures into the general fund & trust council to figure out what to do with it.
On the balance I think I’m glad the 25% sidewalk & safety amendment passed.
But I respect EPG for raising the issue & am glad to see council having the conversation.