1. Unit 10
Statistics
Part 1

2. Basic Concepts asking questions to subjects
– recording information that has already been made available
– apply treatment to the subjects and record/compare results

3. Three principles of experimental design
– Use chance to assign experimental units to the treatments.
– Assign multiple subjects/experimental units to each treatment
– compare multiple groups, ensure realistic setting, use a control group and/or placebo group, blind/double blind your study

7. Basic Concepts
__________________- in statistics, all of the items of interest.
Ex. All students at CHS
____________- in statistics, some of the items in the population.
Ex. Students in this class

8. Sampling Concepts
every individual in the population has an equal chance of being chosen
- break the population down into smaller groups (clusters) and randomly select clusters to make up your sample
– Break down the population into smaller groups that have something in common, and then randomly sample from each group.

9. Sampling Concepts continued
- every Kth individual is chosen.
- a selection of individuals based on ease of reaching them.
– individuals who decide to participate in response to an open interview.

13. Sample Populations avoiding Bias
Individuals in a sample population
Must be a fair representation of the entire pop.
Therefore sample members must be randomly selected (to avoid bias)
Example: if you were looking at strength in students: picking students from the football team would NOT be random

14. Is there bias?
A cage has 1000 rats, you pick the first 20 you can catch for your experiment.
A public opinion poll is conducted by interviewing students at the local college.
You are conducting a study of a new diabetes drug; you advertise for participants during the Super bowl.