David's Posts

Recent posts clearly place me in the camp of “critic” for the sales tax data from Grand Forks. Criticism can be important because it encourages us to make things better, to improve upon the inadequate. With that in mind I offer up some alternatives that might be better than the current system. If we need to remove some of the “ups-and-downs” of the data, for whatever reason, let’s try to keep the some of the features of the data that keep us in the realm of informing policy. This first graph is for a long period of time and may be a bit difficult to see. 

Continue reading Smooth Alternatives: Grand Forks Sales Taxes

Read more

Last week I argued (here) that the city’s use of the rolling twelve month total was not really about accuracy as much as stability. Essentially the two concepts are conflated in the presentation. I still fail to see the virtues of knowing the total sales over the last twelve months, and how it better informs policy decisions. I present the following graphs to demonstrate my points about stability. Here is the monthly collection amount (recall there is approximately a two month lag between sales tax collections and the reported amount).

Continue reading Grand Forks Sales Tax: Accuracy v. Stability

Read more

I used the same data that I used for the map yesterday but plotted the ratio against median total earnings. Partly this was to see if there is a pattern to discern in North Dakota counties such as higher median earnings leading to an increasing or decreasing parity ratio. To assist in this examination, I added a linear regression line and a confidence interval and this is what I found. 

Continue reading Male-Female Earnings Ratio in ND, A follow up

Read more