planetwater

ground- water, geo- statistics, environmental- engineering, earth- science

What are Random Numbers?

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I did a wonderful #statistics experiment with students in stats class the other day on random numbers:

I divided the class into two groups. I gave a coin to one group and told them to flip this coin 20 times and record the resulting sequence of heads and tails. I asked the other group to come up with sequence of heads and tails in their heads and record the best sequence they can come up with. I told them I would leave the room and come back after five minutes, look at both sequences, and tell them which was created by the coin and which one in the heads of the other group.

These are the two sequences they came up with

HTTTTHHTHHHHTTHHHHTT

and

HTHTHTHTHTHTTHTHTTTH

missing
Two “random” sequences created during statistics-class. Which one was created by a coin-flipping experiment?

Can you guess which sequence was constructed by what group?

Here is some background:

Written by Claus

June 24th, 2019 at 4:25 pm

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ssh fun

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I have setup a raspberry pi as a measurement computer. Now I can access it

a) on my Mac by mounting a directory, using SSHFS 2.5.0 via

sshfs -o volname="<MOUNT_NAME>" <USER>@<IP_ADRESS>:<directory_on_raspberry> <directory_on_my_mac>

b) on my iPad! I use OpenTerm to ssh into the machine, run scripts, and I use ShellFish (currently in beta) to basically mount the directory with the output into the file system (I mean into the Files App) on my iPad.

Whoooopeee!!

Written by Claus

June 14th, 2019 at 1:41 pm

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Starting a New Blog

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I had linked to a post by Peter Rukvina’s last time. I am doing it again – this time he linked to Rosie, who started a blog in 2019 called “press pound”.

I can’t applaud Peter’s comment enough:

I’m happy to see the corner turn from “why did blogging die when we loved it so?” to “I’m going to start a new blog!”

Written by Claus

June 11th, 2019 at 12:57 pm

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Moving to Personal

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Since I while I have a new job at the Research Facility for Subsurface Remediation (VEGAS) at the University of Stuttgart (link to newly setup webpage and twitter presence). I’ve been thinking about it for a while and came to the conclusion that both this blog and the associated planetwater twitter presence will move to more private conversations, although still associated to water.

As a first, I want to give a shout out to Peter Rukvina at ruk.ca. There is a lot of talk about a renaissance about the open web. A renaissance of RSS. A renaissance of blogging. Peter has been there since before I started to be there — and he is still there, stronger than ever! His recent post, My Own Private Underhay, is an orbitruary on surface. Really, he is laying out his way of life. He boils it down to this:

What I have started to do, in my daily life, is that when I’m faced with small forks in my road–take the car or take the bike? watch TV or join a committee? have a nap or call my mother? order pizza or learn to make pizza? –- I will take the fork that, while it might be a little harder, require a little more effort, might take me out of the realm of things I’m comfortable doing, is the fork that’s best for my family, my community, and the planet.

I encourage everyone to go to Peter’s site and check out his humanitarian- printing- open- (source) and overall kind- ness!

Written by Claus

May 20th, 2019 at 4:20 pm

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Ein Regengenerator der anderen Art… nicht multi-site und nicht vektor-autoregressiv, aber trotzdem schön… 🙂 https://rainbowhunt.me

Written by Claus

January 3rd, 2019 at 11:13 am

Posted in pw.micro.blog

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Hello World from micro.blog!

Written by Claus

November 8th, 2018 at 11:12 am

Posted in pw.micro.blog

come to AGU18 session “H114: Space-Time Data and Models”

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I would like to invite you to the following session at #AGU18:

The problem of estimating a variable at unobserved locations and/or times is important for many areas of research, including geosciences, civil-/ environmental engineering, soil sciences, agriculture, ecology, forestry, meteorology / climatology, oceanography, health / epidemiology.

The amount of data gathered is increasing (e.g., advances in measurement technologies, remote sensing, or citizen science). Challenges remain related to the interplay between heterogeneous measurements and improvements in models that can make use of the various types of data. This session aims to bring contributions together that demonstrate how to improve datasets and maximise their use through measurement techniques, statistics, and modelling, e.g., via

  • innovative ways to measure data in the environment;
  • the incorporation of innovatively measured data into modelling (usefulness, relevant scale);
  • the inclusion of as much information as available to improve prediction (secondary / heterogeneous data, data on different scales);
  • the consideration of the variability in the quality of the measurements;

Please find a pdf about the session here.

(cross-posted from claus-haslauer.de)

Written by Claus

July 30th, 2018 at 4:41 pm

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Tagged with ,

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How to Filter a List in Python; also: how to compare two results of %timeit

Written by Claus

May 16th, 2018 at 9:02 pm

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Breaking Twitter?

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Twitter might soon be broken (#BreakingMyTwitter). Really, third party clients might be broken, due to API changes. More details are available at apps-of-a-feather.com, a website from a group of third party twitter clients.

I am happy with Twitterrific, both on the mac (both before and after the revival) and on iOS. I have never used a native twitter client on any OS. I am not sure since when it is known that the end of the third party clients could be near. Version 5 of Twitterrific has been out since October 2017. Was it known then?

Now, as I have posted before, I appreciate the free web. The existence of this website is evidence of this. I guess, a lot of things can happen until June. It would be nice if open alternatives (e.g., micro.blog, mathstodon) would gain more users. On the other hand, on work-related topics, it seems like Twitter has recently stepped over a critical mass threshold, and I do enjoy the conversations there. Yet again, I know people who leave twitter, because of trolling and because of being not open. As they say, the future remains interesting!

Written by Claus

April 9th, 2018 at 8:05 pm

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Getting Ready for #hymod18

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To get ready for the “Integrated Hydrosystem Modelling 2018″ Conference”s, about to start in a couple of hours, I played with a watershed on my sofa and a bivariate Gaussian distribution on my coffee table

Both apps are enabled via Apple’s ARKit:

  • GeoGebra has an app called “GeoGebra Augmented Reality” that allows you to plot functions of two variables on a surface that you can pick, like my coffee table. You can then rotate, walk around it, look on top of it and explore in other ways those functions. Great fun!
  • The WWF Free Rivers app puts a simple watershed on a surface you can define (like my sofa). Then clouds move in, and you can paddle down the river. Maybe more for kids. Still fun.

Great to see such nice use cases, and let’s get ready for integrated hydrosystem modelling #hymod18!

A watershed on my sofa
A watershed on my sofa.

a bivariate Gaussian density function on my coffee table
A bivariate Gaussian density on my coffee table.

Written by Claus

April 3rd, 2018 at 6:48 am

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