Class #2: Biostatistics

It's Wednesday, hard to believe that this week is already coming to a close (or that August is just a few days away) -- so here's what's cooking this Friday:

We are honored to have Dr. Naihua Duan offer an Introduction to Sampling presentation this Friday at 9:30 AM. Please plan to be here around 9 AM, so that we can start promptly. If you are curious about his recent work, here are some of his online publications:

• Sample Size Determination for Studies with Repeated Continuous Outcomes
• Missing Data in Longitudinal Clinical Trials Part A: Design and Conceptual Issues

We will then be attending Grand Rounds with Linda Fried at 11 AM.

Please read this excerpt from the book, "Designing Surveys" to become more familiar with the science of surveys for this Friday.

Bye for now!

What sort of careers use sampling techniques?

So we've finished our first class. In the future (like next week), here's the procedure to follow for each class:

• Check this blog on Wednesdays to learn about what that week's Friday class will be about.
  
• Be prepared at the beginning of class to complete any "pre-assessment" requirements posted on the blog
• After each class will be a writing assignment, designed to help you with your final writing requirement concerning pursuing a career in science. You will save your work to the class wiki

For this class, I would like you to do three things:

1. Post a comment to this blog concerning my summary of your interests in science we discussed two Fridays ago. Let me know if I should revise your summary in any way, or if I should add any additional interests.
2. As a group, I would like all of you to describe how we reached a consensus that there are 11,215 tombstone in Trinity Cemetery. Post your reflections on the wiki page. Feel free to edit other students' text if you feel it is inaccurate or missing an important detail. The full set of instructions are listed on that page.
3. Finally, I would like everyone to choose a scientific career that uses sampling techniques from the list of links below. I would like everyone to choose a different career path for investigation. If you have a burning desire to research a career not listed, email me a link with a description/example of the career you want to research and I'll make sure it's OK to research. Here are the links to the various scientific careers that use sampling techniques in the job:
   

• Internet survey methods
• Fashion adoption | Ethnic consumption
• Scent marketing
• TV and fast food eating behavior
• Surveying homeless populations
• Iraqi civilian deaths
• Measuring unemployment

Once you have read the information in the link, go to your wiki page, and answer the questions listed on the page. To edit a wiki page, click on the 'Edit' button on the top right side of the page, and type in your comments. Most importantly, please remember to click the 'Save' button on toolbar to save your comment. Clicking File | Save from the menu will not save your work, so don't do that.

Here are the summaries, so please post a comment at the bottom of this posting if I should change your summary in any way.

Jakob Layman

Expressed interest in "neuroeconomics." Additionally, how are space age "green" polymers different from their original chemical structures (e.g., biodegradable, create more efficient laminar flows).

Maritza Montanez

Selected as an area of interest language formation. Specifically, what are the effects when immigrants losing the ability to use their native language on their connection to their native culture. Along a similiar line, what are the contrasts between large city medical institutions, and small town folk remedies. Finally, what are the relationships between stress and not having health insurance.

Geraldine Diaz

Generally speaking, what is the relationship between criminologists and urban populations, focusing on the sociological aspects.

James Rini

Has an interest in the relationship between brain morphology and psychological disorders, such as neorogentica of schizophrenia, transgenic mutations, reverse engineering of the 1918 flu. Additionally, he listed some technological interests, such as cold fusion, batteries of the future, and opposing theories to global warming.

Kennesha Dickson

Offered a most generalist perspective. Her question was, "what is the relationship between (boring) research and (interesting) applications, such as social services and counseling?" She also mentioned interest in the relationship between juvenile delinquency and genetics and crime.

Dayna Heckstall

Addressed more ethical, rather than purely scientific concerns, Generally speaking, "what is the role of public health? What actions are ethically justified in a scientific investigation?"

Soulkya Agana-Woodbine

Has a personal interest in gentrification, specifically of Bedford-Styvesent. Maybe this would be a good place to have a GIS module.

Here's how you post a comment to this blog:

• Scroll to the end of this posting, on the line that starts, "posted by terminus," and click on the 'comments' link.
  
• On the right side of the screen, type your name in the text box.
  
• Answer the questions listed above, under your name.
  
• Below the text box, click on the 'Anonymous' radio button.

That's it! Please check back on Wednesday to find out what's up this Friday.

Class #1: How many tombstones are in Trinity Cemetary?

Welcome to Stimulus Science!

Hopefully this storm will clear out by morning, and we'll able to sun ourselves at Trinity Cemetery. New York City cemeteries are fascinating objects of study. The original solid state databases, you could spend your life mining their data-rich substrates. We will invest a simple question, and apply a basic scientific technique this Friday. Your mission, should you choose to accept it, is to figure out how many tombstones are in Trinity Cemetery.

If you take "Biology 101" in college, you'll likely experience some field work, where field really means walking a field, and your work will be trying to figure out the number of some species living in the field. You may smirk at the simple minded task, but take a moment to think about what sort of scientific procedures you may have to implement in order to establish a valid number. People spend their lives, writing books about this seemingly simple task.

The key issue in this sort of investigation is finding a scientifically credible way to be lazy, that is, not count all of the objects of inquiry, and yet claim to know to a reasonable degree of certainty, what the total number of objects is. In other words we need to sample a limited number of objects of interest, and project from that number, what the total number of objects in the field is.

The biggest problem to sampling is making sure your sample isn't biased. We could overlay a grid on the field, and count the number of objects in every third square of the grid. But systematic sampling isn't necessarily representative sampling. Can you think of a case where picking off every third object would lead to a biased result? Here's an example.

The key, therefore, is to develop a random sampling technique. What I'd like you to think about between now and our field trip, is what sort of scientifically credible way could we sample a number of tombstones from Trinity Cemetery, and deduce the total number of tombstones in the cemetery. You don't have to read everything in the links provided, but think about the question, and get ready to develop a scientific procedure on site tomorrow!