2.3 Designing a Study

We’ve spent some time now programming and working with data structures. Let’s start our delve into statistics!

The Sample Frame (slides)

What are some important things to keep in mind as we design statistical studies? We will discuss sample frames, as well as issues that may arise.

⊕ observational samples, correlation vs causation
⊕ sample frame
⊕ coverage bias
⊕ probability vs nonprobability sampling
⊕ selection bias

Once we have chosen our sample frame, how do we actually obtain samples?

⊕ quota, convenience, voluntary
⊕ simple random, interval, stratified, cluster
⊕ non-response and response bias

Choose one of the following situations:

A 3rd grade teacher is interested in childhood literacy development. They’ve noticed that some students tend to perform better when asked to do reading tasks. The teacher is curious about what reading activities these students are doing at home.
An outdoor enthusiast recently went hiking, and found that some blueberries on the side of the trail were extremely sweet. However, other bushes on the same trail produced tasteless blueberries. The hiker is intrigued by what could be causing this difference.
An independent publisher is looking at printing presses to partner with. They are focused on newspapers and want to find a company that is experienced with newsprint paper. The publisher is thinking about what qualities to look for.

Then, for your chosen situation, write a response to the following:

Identify a statistical question you could ask in that situation.
Identify the population you would study to answer the question. What information about the population would help answer your question?
Identify a feasible sample frame, and explain your reasoning.
Identify the sampling method you would use, and explain your reasoning. What makes this method better than the others?
What biases may come up, and how would you address them?