Here is a new publication that I worked on with a current and two former graduate students. In this study we try to understand the value of reported Covid-19 data (mostly based on positive SARS-CoV-2 test results). Our conclusion is that the data are not terribly useful over short time horizons. This doesn’t call into question the overall value of data sharing, but does call into question the value of daily news reports about the rise and fall of positive Covid-19 tests.