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pedvide

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That depends on what your hypothesis is. If it is that Waymo cars are safer than for-hire (which I guess it's what Waymo claims), then you need enough data to reject the null hypothesis that they are equally safe. Right now there doesn't seem to be enough data to do this, so you can't conclude they are safer. They could be equally safe or more dangerous.

I've taken long exposures using film (analog, so no stacking or any other funny business) and saw the same thing. I always thought they were planes but now it seems they may have been satellites. I'm curious if someone knows why this happens

I've always understood "free as in beer" as: if someone hands you a beer and says it's free, you know that you don't have to pay to consume the beer, but that doesn't mean that you also get the recipe, brewing instructions, factory plans, glass making instructions etc. The only thing that is free is the liquid itself, nothing else.

Part of my PhD involved lots of fluoride synthesis using HF. I always used gloves (changing them very frequently). My advisor never used them for the following reason: if a droplet of HF lands on your glove you won't notice, but HF will go through the glove. If it lands on your bare hand chances are you'll notice it and wash them immediately. I could never follow his advise, but I did change gloves pretty much every step in the synthesis just in case.

Cool idea! I can't seem to be able to find information about the maps though, like date, author or something similar. I'd really like that!

In pandas for example that can happen often: `df["count"] == 5` and `df.count == 5` are logically different expressions that will give different answers