Activity 2

MATH 216: Statistical Thinking

Sampling Methods & Study Design Analysis

Time Allocation: 15 minutes total

Part 1: Sampling Bias Analysis (5 minutes)

Scenario: A university wants to understand student opinions about campus dining services. They send an online survey to all students via email.

Questions:

  1. Identify two potential sources of sampling bias in this approach

  2. For each bias identified, explain how it might affect the survey results

  3. Suggest one specific improvement to the sampling method that would reduce bias

Part 2: Survey Question Design (5 minutes)

Original Question: “Do you support the university’s efforts to address climate change through sustainable dining practices?”

Analysis:

  1. Identify two ways the wording of this question might influence responses
  2. Rewrite the question to be more neutral and less leading
  3. Explain why your rewritten version is more statistically appropriate

Part 3: Experimental vs. Observational Study (5 minutes)

Research Scenario: To examine whether farm-grown salmon contain more omega-3 oils if water is more acidic, researchers collect samples of salmon and water from multiple fish farms to see if the two variables are related.

Questions:

  1. Classify this study as either Experimental or Observational
  2. Provide two specific reasons supporting your classification
  3. If this were an experimental study instead, describe one key change researchers would need to make to the design