1.3 – Introduction to Experimental Design Vocabulary Census Sample Simulation

Basic guidelines for planning a statistical study: 1.First, identify the individuals or objects of interest. 2.Specify the variables as well as protocols for taking measurements or making observations. 3.Determine if you will use an entire population or a representative sample. If using a sample, decide on a viable sampling method. 4.In your data collection plan, address issues of ethics, subject confidentiality, and privacy. If you are collecting data at a business, store, college, or other institution, be sure to be courteous and to obtain permission as necessary. 5.Collect the data. 6.Use appropriate descriptive statistics methods/ inferential statistics methods. 7.Finally, note any concerns you might have about your data collection methods and list any recommendations for future studies.

Experiment vs Observation Observational Study: Experiment:

Experiments and Observation Placebo Effect: Control Group: Lurking/Confounding Variables: Replication: Bias:

Experiments Randomized Two-Treatment Experiment: Double Blinded Experiment:

Guided Exercise #5 With table partners, turn to page 22 – Cover answers – Discuss answers Check – Whole group clarification

Surveys Survey Keep in mind: Are questions asked in a neutral way? Are biases built into wording? Is the interviewer giving subtle feedback that influences the response? How can you make sure the respondents are being truthful? Is the sample representative of the population?

Surveys Likert Scale: Pitfalls: – Nonresponse: – Voluntary Response: – Hidden Bias: – Other Variables – Generalizing Results:

Guided Exercise #6 With table partners, turn to page 24 – Cover answers – Discuss answers Check – Whole group clarification

Checkpoint  Explain the importance of random samples  Construct a simple random sample using random numbers  Simulate a random process  Describe stratified, cluster, systematic, and convenience sampling.

Homework Read Pages – Take notes on what we have not covered Do Problems – Page 25 (1-4) Not multiple choice! Check odds in back of book Read and preload Review information – Page Know vocabulary Try Chapter Review Problems (not graded, but helpful)