plastic bag ban has negative effects on local economy (Austin: buying, exemptions)

[Austinite101]

They definitely cherry picked their data. This is a totally worthless "study".

[Trainwreck20]

Plus, they do not address any other potential reasons for the change in sales - population shifts come to mind, for starters......

[OpenD]

The only study that really matters to me is the one where I look at how this would affect me personally:


PLEASE ANSWER THE FOLLOWING:

1) Would you switch to reusable bags if stores stopped giving out disposable plastic bags [ ] No, [X] Already have

2) How far out of your way would you drive to get free disposable bags? [ ] 10 miles, [ ] 5 miles, [ ] 1 mile, [ ] 3 blocks, [X] Are you kidding me?

Thank you for participating in my consumer survey. Your viewpoint is important to me.
Have a nice day.

[scm53]

Originally Posted by Austin97

80 large stores, 700 small stores. Response rate was 3%. 23 stores is not a large enough sample to draw any conclusions.

Yet, presidential polls that have 3,000 responses out of 169,000,000 registered voters are ....?

OK, I get that you and Austinite101 are on a "kill the messenger" mission. Care to share with the rest of us your market research bona fides that give either of you the experience to question the sample size or the "legitimacy" of this survey? Gallup puts their reputation on the line for a .001% response rate, but you throw stones over one that is 3000 times larger?

You might not like the orientation of the self-declared "non-partisan" National Center for Policy Analysis. (sorta like the "non-partisan" Tax Policy Center...). They might not be impartial. But unless you can point to a methodology flaw, accepted by experts, and not just people that don't like the findings, then you are the ones with a "neutrality" problem.

[Dog_Gone]

I use plastic bags as liners for garbage as well. I consciously make that decision when I need them. Otherwise I take my reusable bags.
If you have a grocery list you can plan and estimate the number of bags you will need to take. It only takes a couple of trips to estimate this.
But, it is easy to convince just about anyone today that thinking might just hurt your head. Most people operate with about an 8th grade level of education. The brainwashing is easy when you are dealing with that mentality.

I did see an interview about a year ago and an advocate for the plastic industry said, with a straight face, that that these plastic bags and plastic in general does not harm the environment.

[Austin97]

Originally Posted by scm53

Yet, presidential polls that have 3,000 responses out of 169,000,000 registered voters are ....?

OK, I get that you and Austinite101 are on a "kill the messenger" mission. Care to share with the rest of us your market research bona fides that give either of you the experience to question the sample size or the "legitimacy" of this survey? Gallup puts their reputation on the line for a .001% response rate, but you throw stones over one that is 3000 times larger?

You might not like the orientation of the self-declared "non-partisan" National Center for Policy Analysis. (sorta like the "non-partisan" Tax Policy Center...). They might not be impartial. But unless you can point to a methodology flaw, accepted by experts, and not just people that don't like the findings, then you are the ones with a "neutrality" problem.

The methodology flaw is that from too small samples (23) you cannot draw ANY conclusions. You can go to any stats 101 textbook and find that the minimum sample size to make any kind of judgement is 30 units. Even then you may not be able to because of variance in the samples. 3000 is sufficiently large, but may not be representative. There are two aspects, precision and accuracy. 3000 is actually precise but may not be accurate.

23 is not a large enough sample to be precise, which means accuracy isnt possible.

Moreover they did not cite their standard deviations or their confidence intervals. In statistics if my average before is 80 and my average after is 90, there might not be any statistical difference. Even if the average is 80 before and 160 after there might not be any difference.

This statistical failure is sufficient to completely invalidate their "study"

[austin-steve]

Originally Posted by Austin97

This statistical failure is sufficient to completely invalidate their "study"

Just curious, what studies were done to justify the ban, and were those studies conducted in a way that "passes the test" of good statistics?

Steve

[sxrckr]

I generally don't like the things, but have used them as trash liners.

Why not find a middle ground? There are companies that produce additives that are added to plastics to make them biodegradable. Why not offer only biodegradable plastic bags?
Fast food places should do this with their containers too. And promote it. These days, green sells.

[scm53]

Originally Posted by Austin97

23 is not a large enough sample to be precise, which means accuracy isnt possible.

Guess in your rush to discredit a study you don't like, you blew right past the 80 large stores that made up the bulk of the study?

Besides, the small stire part population was 700 - the response was 23. I have commissioned enough market reserach (vice stats) to know that IS a valid response rate, as long as you fully disclose what the conficence interval is. By my bar math, that comes out to about a 20 confidence interval with that sample size. Even if you figure that interval in, it doesn't change the finding of that part of the study, they did - you just want to shoot holes in it as much because you suspect the politics.

What did you want them to do? Pass an ordinance that the small stores in unincorporated areas had to respond? Oh, wait. That is Austin where people use the power of law to get people to do things they can't educate them into doing. Silly me.

[Austinite101]

Originally Posted by scm53

Yet, presidential polls that have 3,000 responses out of 169,000,000 registered voters are ....?

OK, I get that you and Austinite101 are on a "kill the messenger" mission. Care to share with the rest of us your market research bona fides that give either of you the experience to question the sample size or the "legitimacy" of this survey? Gallup puts their reputation on the line for a .001% response rate, but you throw stones over one that is 3000 times larger?

You might not like the orientation of the self-declared "non-partisan" National Center for Policy Analysis. (sorta like the "non-partisan" Tax Policy Center...). They might not be impartial. But unless you can point to a methodology flaw, accepted by experts, and not just people that don't like the findings, then you are the ones with a "neutrality" problem.

Since when did I "kill the messenger"? I never attacked you. Also, I don't need market experience to know what is questionable and what is not. And this, my friend is questionable. Furthermore, the study is far from comprehensive. It only surveys a small number of businesses in one geographic location of the country. To be accurate, you would need a massive response from multiple cities all over the country who have done the ban. To complicate matters more, you have to account for population change, the root causes for a decline in consumption other the the ban (for instance, economic conditions), etc. Not to mention that most of the bans that have passed are not the same bans. Some are extremely restricting, others are more loose, and each have their own exemptions to the ban. This study is as botched as they come.