6 more posts in this thread. [Missing image file: F5.png]
Wondering if someone can help me out and solve this. If not, cool. Someone asked me to do it, and Im far too lazy/dumb to figure it out at the moment.
Questionnaires were mailed to 5,000 people who were selected randomly. Each person was asked to list age, sex, smoking habits, and respiratory symptoms during the preceding seven days. About 80% of the questionnaires were completed and returned, making the final completed sample of 4,000.
There were 1,100 total smokers in the sample. There were 1,000 respondents who had respiratory symptoms. About 700 of the respondents reported having upper respiratory symptoms and also smoked. There were 2,600 respondents who neither smoked nor had any respiratory symptoms. But there were 400 who smoked but had no respiratory symptoms.
Calculate the odds ratio of the disease and exposure.
13 more posts in this thread. [Missing image file: Fuel Economy.png]
Can we discuss the history of fuel economy in cars and trucks?
Refer to the pic. In response to the oil crisis in the early 1970s, Congress passed some standards that called for doubling the passenger-vehicle efficiency within 10 years in 1975. This can be seen in the figure with car fuel economies going from about 13 to around 26 mpg. But then from about 1985 to 2005, fuel economy remained constant. I'm finding it hard to believe that for 20 years, no progress was made on technology that could make cars more energy efficient. I'm wondering why you think this is the case. Here's a couple of my ideas. Please discuss them and also present your own.
1) Fuel prices remained relatively low so there was not much pressure to increase fuel economy.
2) Energy companies subsidize research of the auto industry. As such, if some company comes out with a 50 mpg car, for example, they cease to fund this company, making it harder for this company to compete. This may seem like a 'conspiracy,' but really it's just pure economics. Why would an energy company spend money to see more efficient vehicles? This would result in them selling less fuel.
3) Car companies intentionally keep fuel economies low for sake of ensuring their long term success. Ex: Say an alternate fuel vehicle hits the market with lower fuel prices. Car companies can then compete by improving their fuel economies, effectively making their fuel prices lower and out competing the new technologies/new fuels.
Do you think any of these theories hold water?
Source for pic: http://www.pewenvironment.org/uploadedFiles/PEG/Publications/Fact_Sheet/History%20of%20Fuel%20Economy%20Clean%20Energy%20Factsheet.pdf
Education system and validation
50 more posts in this thread. [Missing image file: Philosoraptor.jpg]
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Here are some of my thoughts on the education system and how it rewards certain types of students. Please tell me what you think.
Tl;dr: I dont think it is good for test scores and grades to be rewarded because it makes recipients validate themselves. And, those who dont
get the high test scores and grades feel ashamed and inferior. The students who don't recieve high grades/test scores are no less important than the students who do. The high scoring student is just as human (and potentially just as useful to society) as a low scoring student.
I think it is important to ask ourselves why we reward these high test scores.
Is it to motivate other students to do better?
This would imply that success in the world is directly determined by how well you do in school. They may be related, but
I do not believe that- beyond doubt - it can be proven that high scores and high grades cause success in society. One can make
an important contribution to society without having high test scores.
Often, the opposite is what happens. In order to rationalize their apparent inferiority, students will begin to tell themselves
that school, and more importantly inquiry and knowledge, are not important.