The Monty Hall Problem

December 2nd, 2015 | Brain

The Monty Hall Problem - 3 doors

The Monty Hall Problem is a famous statistical brain teaser that has caused never-ending debate over the past 30 or 40 years. It is based on the old TV gameshow “Let’s Make A Deal,” which was hosted by Monty Hall, and it goes something like this:

There are 3 doors. Behind 1 door is a fancy car, and behind the other two doors are goats. You first make a choice of one of the three doors. Then Monty Hall open up one of the remaining doors with a goat behind it and then asks you if you want to switch your guess to the remaining door or keep with your originally guessed door. So the question is: should you switch?

The answer is not very intuitive and sort of messes with most people’s basic understanding of statistics.

Here’s the quick answer: YOU SHOULD ALWAYS SWITCH!

Here’s the longer explanation:

The door you originally picked has a 1/3 chance of having the car both before and after Monty gets involved. When Monty picks one of the remaining doors to open with a goat behind it, that doesn’t change the statistics of the scenario. Crazy, right!?

So that means there is a 2/3 chance that the two doors you did not pick have the car. From those two, Monty eliminates a bad door. The remaining unpicked door still has a 2/3 chance of having the car, even though you are staring at just two unopened doors. That’s higher than 1/3, so you switch.

Most people forget the the host knows where the goats are. If you pick door 1, you have a 33% chance of getting it correct and a 66% chance of being wrong. Essentially what you’re being offered at the 2nd part is that if there is a car behind either of the doors you didn’t pick you win. Which is 66%.

Here’s the 3 possible scenarios that can be played to make it even more clear:
You pick door 1. The car is behind door 1. The host opens a door with a goat behind it (either door 2 or 3, since they both have goats).

You switch, you lose.
You stay put,you win.

2)

You pick door 1. The car is behind door 2. The host opens a door with a goat behind it (thus has to be door 3, since the car is behind 2, and you’ve chosen door 1)

You switch, you win.
You stay put, you lose.

You pick door 1. The car is behind door 3. The host opens a door with a goat behind it (thus has to be door 2, since the car is behind 3, and you’ve chosen door 1)

You switch, you win.
You stay put, you lose.

Switching = 66% success rate
Sticking = 33% success rate

If you are still not convinced, you can play around the the odds at this online simulation

http://www.montyhallsimulation.com/

 

-RSB

Saturn V Cutaway by Stephen Biesty

November 24th, 2015 | Space

Saturn V cutaway

(Click to enlarge)

The Saturn V was a NASA rocket used between 1966 and 1973. It is the only launch vehicle that has been able to transport humans beyond low Earth orbit, making it responsible for bringing 24 different astronauts to the Moon.

I love these sort of infographics because they give you a sense of the design and engineering that went into these colossal machines. This illustration comes from a Stephen Biesty Incredible Cross-Sections book. Looking through these books is giving me a strong rush of nostalgia for the countless hours spent in my youth pouring over all of these intricate details.

-RSB

New Martian Spacesuit Revealed

November 11th, 2015 | Space

New Martian Spacesuit

NASA recently released a new prototype spacesuit for future Martian exploration. The Z-2 design can effectively “dock” with a Mars rover or with some sort of habitation placed on the surface. A little like this:

New Martian Spacesuit 2 docking

A major advantage of this sort of design is that you can keep the Martian dirt on the outside and never track it through an airlock.

Of course, this design will likely go through many more iterations in the next two decades leading up to launch. If you want to get involved, NASA is looking for new astronauts! The job application opens in December, 2015. You need to have at least a bachelor’s degree in Science, Engineering, or Math with a few years of experience in those fields. Best of luck!

-RSB

Biisuke Ball’s Big Adventure

October 28th, 2015 | Robot

Biisuke Ball's Big Adventure

Rube Goldberg machines are all about taking as many steps as possible to do something really simple. In this clip from the Japanese educational television program, PythagoraSwitch, a small red ball called Biisuke travels through a Rube Goldberg machine to rescue his yellow and green-colored brothers from the ball prison. It’s a pretty neat idea to turn the classic RG machine into an epic quest.

You can find more small machines on the program’s YouTube page.

-RSB

[via Colossal]

Namib Dessert via the ESA Satellite

October 12th, 2015 | Space

Namib Dessert ESA Satellite

Fire & Ice… The red hue comes from the iron oxide which is plentiful in this area of the Namib dessert of Namibia. BUT, the colors are not quite realistic. This is one of the European Space Agency satellite photos that have been recolored as part of an art/science collaborative exhibition called Spaceship Earth.

Here the location via Google maps if you are curious: link.

And here a few more of my favorite images from taken from ESA satellite:

ESA photo 2

Ganges’ Delta

ESA photo 3

Peruvian Landscape

ESA photo 4

Agricultural crops in Aragon and Catalonia

-RSB

Blue Brain Project Simulates 30,000 Neurons of Rat Brain

October 9th, 2015 | Brain

FIGURE 13_Spontaneous activity v3

The European Blue Brain Project to simulate the rat brain has finally bore its first fruit. Researchers spent over 20 years of biological experimentation and 10 years of computational science work to get to this point. The project has been hotly contested across the science world. Last year, more than one hundred neuroscientists threatened to boycott the project unless significant changes were made. More than 1 billion euro was funneled into the project by the European Commission, and many scientists wondered if anything useful would be created.

But alas, the first findings were published October 8 in the journal Cell, in an article entitled, “Reconstruction and Simulation of Neocortical Microcircuitry.”

“[We] find a spectrum of network states with a sharp transition from synchronous to asynchronous activity, modulated by physiological mechanisms,” wrote the authors. “The spectrum of network states, dynamically reconfigured around this transition, supports diverse information processing strategies.”

This first simulation is meant to represent a “scaffold” on which many more layers of complexity can be added. I think it’s a good first step and hopefully this work can lead to a deeper understanding of the human brain.

-RSB

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