In the last Uncertainty Wednesday post on Sample Variance, I wrote that “Inference from data without explanations is how people go deeply wrong about reality.” It occurred to me that the best way to illustrate this is by writing about spurious correlation. To do that I first have to introduce the concept of correlation though. It may seem surprising that I have gotten this far into the series without doing so, but we spent a fair bit of time on a related concept, namely independence. If you d...

NOTE: One of my goals for 2018 is to bring my book World After Capital to the point where I feel it is good enough to publish in paper form. I have come to realize that if I just keep blogging about other topics at the same time I won’t get there. So going forward every Monday I am planning to post revised pages or whole sections of the book starting today with the sections titled “Work in Progress” and “Preface.” Work in Progress This book is a work in progress. What you are reading now is a...

In the last Uncertainty Wednesday post on Sample Variance, I wrote that “Inference from data without explanations is how people go deeply wrong about reality.” It occurred to me that the best way to illustrate this is by writing about spurious correlation. To do that I first have to introduce the concept of correlation though. It may seem surprising that I have gotten this far into the series without doing so, but we spent a fair bit of time on a related concept, namely independence. If you d...

NOTE: One of my goals for 2018 is to bring my book World After Capital to the point where I feel it is good enough to publish in paper form. I have come to realize that if I just keep blogging about other topics at the same time I won’t get there. So going forward every Monday I am planning to post revised pages or whole sections of the book starting today with the sections titled “Work in Progress” and “Preface.” Work in Progress This book is a work in progress. What you are reading now is a...

Late in 2016 I wrote a blog post titled “Voice Platforms: Open Alternative is an Opportunity.” At the time I learned about a project called Mycroft. This project has just launched its second version, the Mark II, on Kickstarter. If you want voice in your home but are weary of Amazon and Google (and the other tech giants), this looks like an interesting alternative. Here is their intro video, which is super funny in a self deprecating way: I just went ahead and backed the project and look forw...

Late in 2016 I wrote a blog post titled “Voice Platforms: Open Alternative is an Opportunity.” At the time I learned about a project called Mycroft. This project has just launched its second version, the Mark II, on Kickstarter. If you want voice in your home but are weary of Amazon and Google (and the other tech giants), this looks like an interesting alternative. Here is their intro video, which is super funny in a self deprecating way: I just went ahead and backed the project and look forw...

Last Uncertainty Wednesday, I used meteorite impact data to make the point that sample variance may be much smaller than actual variance. Following the post, I was asked a great question on Twitter: “Is there such thing as estimation error on sample variance?” The answer is yes. Just as we saw earlier that the sample mean has a distribution, so does the sample variance. If you have different samples, you will get different variances and those will form a distribution. We are thus faced with e...

Last Uncertainty Wednesday, I used meteorite impact data to make the point that sample variance may be much smaller than actual variance. Following the post, I was asked a great question on Twitter: “Is there such thing as estimation error on sample variance?” The answer is yes. Just as we saw earlier that the sample mean has a distribution, so does the sample variance. If you have different samples, you will get different variances and those will form a distribution. We are thus faced with e...

It appears that some people genetically need only 4 hours of sleep per night. Well, I am not one of them. I also don’t seem to be needing less sleep as I am getting older. Instead, I have come to appreciate how critically important sleep is for me. Looking back, many of my worst decisions, as well as my worst behavior, correlate with periods of insufficient sleep (or excessive jet lag for that matter). The particular effects of not sleeping enough for me areL I become short tempered and easil...

It appears that some people genetically need only 4 hours of sleep per night. Well, I am not one of them. I also don’t seem to be needing less sleep as I am getting older. Instead, I have come to appreciate how critically important sleep is for me. Looking back, many of my worst decisions, as well as my worst behavior, correlate with periods of insufficient sleep (or excessive jet lag for that matter). The particular effects of not sleeping enough for me areL I become short tempered and easil...

Towards the end of last year in Uncertainty Wednesday, I wrote a post about suppressed volatility and gave an example. I ended the write up with:if we simply estimate the volatility of a process from the observed sample variance, we may be wildly underestimating potential future variance This turns out to be true not just for cases of “suppressed volatility” but much more broadly. For any fat tailed distribution, the sample variance will underestimate the true variance. Mistaking the sample v...

Towards the end of last year in Uncertainty Wednesday, I wrote a post about suppressed volatility and gave an example. I ended the write up with:if we simply estimate the volatility of a process from the observed sample variance, we may be wildly underestimating potential future variance This turns out to be true not just for cases of “suppressed volatility” but much more broadly. For any fat tailed distribution, the sample variance will underestimate the true variance. Mistaking the sample v...

We have the USV office closed today in honor of Martin Luther King Jr. day. In his book “Where Do We Go From Here: Chaos or Community” he wrote:In addition to the absence of coordination and sufficiency, the [social] programs of the past all have another common failing — they are indirect. Each seeks to solve poverty by first solving something else. I’m now convinced that the simplest approach will prove to be the most effective — the solution to poverty is to abolish it directly by a now wid...

We have the USV office closed today in honor of Martin Luther King Jr. day. In his book “Where Do We Go From Here: Chaos or Community” he wrote:In addition to the absence of coordination and sufficiency, the [social] programs of the past all have another common failing — they are indirect. Each seeks to solve poverty by first solving something else. I’m now convinced that the simplest approach will prove to be the most effective — the solution to poverty is to abolish it directly by a now wid...

It happened on the second to last day of a wonderful family trip to Southeast Asia. I looked at my mobile phone in the morning and it had an alert that said something like “SIM not recognized.” I should have probably figured out something was remiss right then, but instead I simply assumed that my phone had tried to register on an unsupported network. As I was sitting down for breakfast suddenly 3 emails arrived in rapid succession that made me realize I was being hacked (time order is from b...

It happened on the second to last day of a wonderful family trip to Southeast Asia. I looked at my mobile phone in the morning and it had an alert that said something like “SIM not recognized.” I should have probably figured out something was remiss right then, but instead I simply assumed that my phone had tried to register on an unsupported network. As I was sitting down for breakfast suddenly 3 emails arrived in rapid succession that made me realize I was being hacked (time order is from b...

So I am still away on family vacation and following a self-imposed online diet, but even then it has been impossible to ignore the monster sized vulnerabilities disclosed today known as Meltdown and Spectre. And just to make sure nobody misreads my post title, these are bad. Downright ugly. They are pervasive, exploitable and a real longterm fix will likely require new hardware (one or more extra hardware bits in the CPU). So how can I possibly claim they are good? Here are four different way...

So I am still away on family vacation and following a self-imposed online diet, but even then it has been impossible to ignore the monster sized vulnerabilities disclosed today known as Meltdown and Spectre. And just to make sure nobody misreads my post title, these are bad. Downright ugly. They are pervasive, exploitable and a real longterm fix will likely require new hardware (one or more extra hardware bits in the CPU). So how can I possibly claim they are good? Here are four different way...

As 2017 draws to a close I will be taking a break from blogging, twitter and (for the most part) email until well into January. I have a great set of book recommendations – far too many to get through for quite some time – and I will be traveling with Susan and our children. Given all the craziness of this year in politics, climate change, technology (crypto currencies) and more, I look forward to getting some distance from it all and spending time with family. I feel incredibly fortunate to ...

As 2017 draws to a close I will be taking a break from blogging, twitter and (for the most part) email until well into January. I have a great set of book recommendations – far too many to get through for quite some time – and I will be traveling with Susan and our children. Given all the craziness of this year in politics, climate change, technology (crypto currencies) and more, I look forward to getting some distance from it all and spending time with family. I feel incredibly fortunate to ...