Stress and Headaches “In the study, researchers… found that the greater the stress in a person's life, the more intense and frequent their headaches were.”
Correlation A = amount of stress B = strength and number of headaches A is positively correlated with B B is positively correlated with A
Explanation for Correlation Possible causal structures: • A causes B • B causes A • Some other variable C causes both A and B.
Researcher’s Explanation for Correlation Possible causal structures: • A causes B • B causes A • Some other variable C causes both A and B.
Explanation for Explanation Stress causes headaches. ↑ Why?
The Article Does Not Say! “Although headaches can be triggered by many factors, ranging from muscle strain to exposure to noxious gases, stress clearly plays a major role.” Clearly? Why?
Posit a Mechanism • Stress causes an increase in the hormone adrenaline. • Adrenaline opens blood vessels for faster flowing blood, and quicker reaction. • Elevated levels of adrenaline over long times can cause the blood vessels in the head to send pain-signals to the brain. • That’s why Stress causes headaches.
Facebook and Body Image Problems “Female students who spend a lot of time on the social networking site tend to be more body conscious and to suffer from more anxiety.”
Facebook and Body Image Problems “They also tend to give greater significance to the number of comments and ‘likes’ on their pictures and status updates. They are more likely to ‘untag’ themselves in pictures.”
Correlation A = time that young women spent looking at pictures on facebook B = unhealthy body image A is positively correlated with B B is positively correlated with A
One Explanation A → B Looking at pictures longer on facebook causes an unhealthy body image in young women.
Mechanism A → X → B Looking at pictures longer on facebook causes women to compare themselves with others and this causes an unhealthy body image.
NOT a Different Explanation A → X → B Providing a mechanism is not the same thing as providing a different explanation for the correlation. This is still the A → B explanation.
Tracing Causes Back X → A → B Having easier access to computers causes looking at pictures longer on facebook, which then causes an unhealthy body image in young women.
NOT a Different Explanation X → A → B Tracing the causes back further is not the same thing as providing a different explanation. Here we are still assuming that A causes B, we are just explaining what causes A.
Widening the Target A → B Facebook and twitter and instagram and tublr and… all cause looking at pictures longer on, which then causes an unhealthy body image in young women. X
Also NOT a Different Explanation A → B Again, this explanation still says that A causes B, it just lists a bunch of other causes of B. X
Sex and Money “[P]eople who had more money, reported more sexual satisfaction.”
Sex and Money “[P]eople who had more money, reported more sexual satisfaction.”
Sex and Money A = socioeconomic status ($$$) B = sexual satisfaction A is positively correlated with B B is positively correlated with A
Tracing Back the Causes X → A → B Being educated causes one to acquire wealth. Wealth attracts better sexual partners.
True Common Cause A ← C → B Being educated causes one to acquire wealth. Being educated also causes one to have a better awareness of one’s need and thus to have better sex.
Doesn’t Always Make Sense A ← C → B Living in a prosperous country causes one to acquire wealth. Living in a prosperous country also causes one to have a better awareness of one’s need and thus to have better sex.
Doesn’t Always Make Sense A ← C → B Everyone in the study was from Spain!
Problem #1 After the nuclear disaster at Fukushima, lots of people rushed out to buy iodized salt. These people thought that “three men make a tiger” and if enough people say something is true, then it is. This is just the appeal to popularity, and it is a bad way to form your ideas.
Problem #1 That is why I know that iodized salt does not protect from nuclear radiation. Based on the information we learned in class, what is the main flaw with this argument?
The Fallacy Fallacy This is a bad argument: • You have presented argument A for your claim C. • A is a fallacious argument. • Therefore, C is false.
Problem #2 Imagine that a school decides to try a new way to teach reading to its students. They use the new teaching method over an entire term and discover that 80% of the students test better in reading proficiency at the end of the term, compared with how they tested at the beginning. The school concludes that the new way of teaching reading works, and they decide to keep using it in the future. Based on the information that we learned in class, what is the main problem with the conclusion the school reaches? What should they have done instead?
There’s No Control Group Of course students will get better at reading after an entire year of teaching. What we want to know is whether the new method works better than the old method. So we need two group: the experimental group using the new method and a control group using the old method.
Problem #3 Neglecting to follow a dentist’s directives can lead to heart disease, high blood pressure, and stroke — and that’s only a glimpse of the possible adverse effects of ignoring the importance of good oral health.
Problem #3 “The scary part is that 40 percent of people with heart conditions have gum disease,” Dr. Kabour said. “The big question they ask is how it happens: Bacteria that grows on the gums affects the inner layer of the heart, which builds up plaque over the years.”
Problem #3 • According to this story, which two variables are correlated? • What is the researcher’s explanation for the correlation? • Please offer an explanation of the correlation that differs from the one provided by the researcher.
Correlation A = gum disease B = heart disease A is positively correlated with B B is positively correlated with A
Researcher’s Explanation There’s a common cause: gum disease is caused by bacteria that grows on the gums. This bacteria also affects the heart, and causes it to build up plaque over many years.
Correlation A = doing what the dentist says B = heart disease A is negatively correlated with B B is negatively correlated with A
Researcher’s Explanation A causes B. Not doing what the dentist says causes bacteria to grow on your gums. This bacteria then affects the heart, and causes it to build up plaque over many years.
Alternate Explanation There’s a common cause: sugar. Consuming sugar causes bacteria to grow on your gums and then causes gum disease. But tooth-decay is NOT what causes heart problems. The sugar does. Sugar causes weight gain and this strains your heart.
Researcher’s Explanation You can tell this is a different explanation because what it recommends is different. Good oral hygiene will not prevent heart disease, if this explanation is true: only removing sugar from your diet will.
Problem #4 Using figures from the last election, researchers discover that districts in Hong Kong that were wealthier (higher average income) were also districts that voted more for pro-democratic politicians from the Civic, Democratic, and People Power parties. Districts that were poorer voted more for pro-Beijing politicains from DAB, FTU, and NPP. Using the information that we learned in class, explain why these results should not lead us to believe that wealthier people are more likely to be pro-democratic.
Ecological Fallacy States with the highest average incomes have a higher percentage of democratic voters. So does this mean that people who are wealthy are more likely to vote democrat? No! The opposite is true.
Nanotips Gloves that work with touchscreens aren’t new, but they’re usually sold at a premium and have to be bought separately from your existing gloves.
Nanotips A new technology claims to solve this problem by letting you turn any pair of ordinary into touchscreen ones simply by painting the fingertips with a special liquid. Called Nanotips, the liquid is made of conductive polyamide that soaks into the fabric and builds a conductive 'bridge' between your finger and the screen.
Nanotips A Nanotips pack costs $20 (£12) but can be used on multiple gloves. Shipping costs $3.50 and it is due to go on sale on 20 March. The company does ship internationally.
It’s an advertisement disguised as news! http://www.dailymail.co.uk/sciencetech/article-2580983/Now-ANY-gloves-work-touchscreen-12-paint-transforms-woolly-fingertips-prosthetic-limbs.html