Correlation vs. Causation

I think the first thing people think of when talking about correlation and causation is that they are the same thing. But they really aren't. Correlation, according to dictionary.com, is  the extent of correspondence between the ordering of two variables. Correlation is positive or direct when two variables move in the same direction and negative or inverse when they move in opposite directions. Causation on the other hand, is when two variables directly effect one another. For example, in you put your dog outside at night and it gets sick, it is likely that it got sick from being put outside. However, the cause of it getting sick could be a virus or a bacteria. 

If one action causes another, then they are most certainly correlated. But just because two things occur together does not mean that one caused the other. For example, many studies are actually designed to test a correlation, but are suggestive of “reasons” for the correlation. People learn of a study showing that “girls who watch soap operas are more likely to have eating disorders” — a correlation between soap opera watching and eating disorders — but then they incorrectly conclude that watching soap operas gives girls eating disorders. 

The most effective way of establishing causality is through a controlled study. In a controlled study, two groups of people who are comparable in almost every way are given two different sets of experiences, and the outcome is compared. If the two groups have substantially different outcomes, then the different experiences may have caused the different outcome.  

Without clear reasons to accept causality, we should only accept correlation. Two events occurring in close proximity does not imply that one caused the other, even if it seems to makes perfect sense.

 

Who's Responsible?

Malaria is caused by a parasite that is transmitted from one human to another by the bite of infected Anopheles mosquitoes. In humans, the parasites travel to the liver, where they mature. They enter the bloodstream and infect the red blood cells. The majority of symptoms are caused by the massive release of the parasites into the bloodstream, the anemia resulting from the destruction of the red blood cells, and the problems caused by large amounts of free hemoglobin released into circulation after red blood cells rupture.

Malaria can also be transmitted from a mother to her unborn baby and by blood transfusions. Malaria can be carried by mosquitoes in temperate climates, but the parasite disappears over the winter. The disease is a major health problem in much of the tropics and subtropics. The CDC estimates that there are 300-500 million cases of malaria each year, and more than 1 million people die. It presents a major disease hazard for travelers to warm climates.In some areas of the world, mosquitoes that carry malaria have developed resistance to insecticides. In addition, the parasites have developed resistance to some antibiotics. This has led to difficulty in controlling both the rate of infection and spread of this disease.

In the book, Silent Spring, Rachel Carson's main purpose is to stop the use of insecticides and pesticides. By doing this, it will increase the rate at which diseases become more and more prevelant in countries such as Africa, the Indian sub-continent, Indonesia, etc. It makes mosquitos more resistant to the insecticides, which could result in an epidemic. Hence, we can say that in a way, Rachel Carson is responisble for the deaths of millions of Africans each year.

What are the Chances of...

1. Dating a supermodel? 
     
     88,000 to 1


2. A male ever being diagnosed with breast cancer?


    1 in 909.1


3. Dying from a shark attack?


    1 in 300,000,000


4. An adult being afraid of spiders or insects?


    1 in 3.7


5. An adult never uses swear words in a conversation?


    1 in 4.76


6. A black adult believing that most Americans are racist?


    1 in 2.17

Mitochondrial Eve

In human genetics, mitochondrial eve refers to the most recent common female ancestor from which all human beings came from. The mitochondrial DNA is passed down from mother to the offspring, and so every living person is somehow descended from this mitochondrial eve. Mitochondrial eve is estimated to have lived around 200,000 years ago, in east Africa.

South African Actress, Charlize Theron 

 Woman from Sub-Saharan Niger

 An Indian woman

 A chinese kid

 An Irish Actress

 There may be a lot of differences between these six people, but one similiarity they do share is the fact that they all have a common ancestor: mitochondrial eve. A lot of the differences they have may have occurred due to adaptation of their new surroundings. Who knows? Maybe a thousand years from now, humans may have evolved and may look different than what they look like now. 

Amphioxus

Amphioxus means when both of the ends are pointed, like the lancelet. It is a small branch under the Animal Kingdom called the cephalochordata. Its important to us because scientists believe that this was the first of the vertebrates, and we, most likely evolved from it.

Polywater

It all started with the Soviet physicist, Nikolai Fedyakin, who performed experiments on the properties of water that had been forced through a narrow capillary tube. The experiments resulted in a new type of water with a higher melting point and a lower freezing point. It also had a higher viscosity than that of ordinary water. 

Boris Derjaguin, a physicist in Moscow, heard about Fedyakin's experiments and improved the production of the new water, even though it was in small quantities. Although his work was published in journals and scientific magazines, no one took notice of it until he went to England and presented his work at a conference. In two years time, the United States was studying polywater as well. 

The main debate between Russian and American scientists was the authenticity of polywater- whether or not it truly existed. Some said that polywater was simply water with small amounts of biological impurities. Others said that the high level of boiling point and low freezing point was due to the impurities present in the water. It took the Russians a little longer to come to the notion that polywater did not exist because they still wanted to cling to the idea. 

http://en.wikipedia.org/wiki/Polywater

http://www.cs.cmu.edu/~dst/ATG/polywater.html

Save the Pacific Northwest Tree Octopus from Extinction?!

This website looks pretty legit when you go onto it for the first time. When I was reading it, there was a tiny part of me that actually thought tree octopuses existed. But then I scrolled down to the bottom where they had some additional links and articles and found the following:

- Save the Mountain Walrus, another species in danger of extinction (and of course, the original link to that was down)

- Rock Nest Monster, Known only from its rocky nests and porcelain-like eggs, Cryptogorgo petronidus is so endangered that existential environmentalists wonder if it ever existed at all. (sounds a lot like something else if you ask me)

However, while doing some reseach on the website, I found that there were many people how fell for the website like I did. In reality, all it was was an internet hoax created by Lyle Zapato, who first started posting about the Tree Octopus in 1998, providing images of purported sightings along with general information about the habits and habitat of the Pacific Northwest Tree Octopus. Lyle's hoax was so well constructed that many people fell for it and continue to fall for, and the hoax even inspired the term “Tree Octopus Problem” to refer to Internet literacy issues.

And oddly enough, the website I went to was http://zapatopi.net/treeoctopus/faq.html, probably created by Lyle Zapato.

I think its amazing what people can make you believe on the internet. Anything can look credible, but I guess its up to you to recognize whether or not it really is true.