## 1/25/2023

## Discussion of Random Rectangles Activity

## The Importance of Randomization

## Different types of Bias

## Major Statistical Concepts from Section 1.4 Reading

- Treatment versus Control Group
- Placebo and Placebo Effect
- Double-blind Experiment

## Step-by-Step Process for Planning an Experiment

- Identify your objective.
- Decide what information to collect.
- Decide how to collect the information.
- Decide how many experimental units are needed.
- Use randomization to assign experimental units to treatments.
- Collect the data.
- Analyze the data.

Gummi Bear Experiments - Conduct an experiment and summarize your results (descriptive stats and visual summaries) in a pdf with the name Design-yourname.pdf. Drop the pdf in your HW folder.

# Descriptive Statistics (with data from Data Survey - Open DescriptiveStats.R)

- Measuring Center
- Measuring Spread or Variability
- Range
- Interquartile range
- Variance
- Standard Deviation

- Measuring Position
- Percentiles
- Five-number Summary
- Boxplot
- Standardized Scores

- Identifying Outliers
- 1.5 x IQR Criterion
- 2 or 3 standard deviations away from the mean

## Class Exercises

The responses on the day 1 data collection survey can be found in the file Google Drive\Stat106-ElementsofStatistics-S2023\!Class-csv-Rscripts\ClassDataS23_Updated.csv. Use this file for the exercises below.

- Compare the amount of texting completed by varsity athletes with those students who are not varsity athletes using descriptive statistics and at least two different graphical displays.
- Compare the pulses for cat and dog lovers using descriptive statistics and at least two different graphical displays.
- Are there any outliers according to the 1.5xIQR criterion for the variable Footlength? PulseRate? Age?
- Are athletes better at guessing the length of the white (black) string than non-varsity athletes? Explain.

## Please read Section 2.2 for class on Friday.