# SOCR Courses 2011 2012 Stat13 1 Lab3b

## Contents

## Stats 13.1 - Laboratory Activity 3

### Summary

This lab is going to serve as a review of what we did in the previous three labs.

### Part 1: Histograms

Follow these steps:

- Go to the SOCR Charts, and click on the arrow next to Bar Charts then XYPlots. Then click on
**HistogramChartDemo**and go to the DATA tab. - Open up another window (or another tab in the same browser window), go to the SOCR Modeler, and click on the
**Data Generation**button. - Choose the
**Normal Distribution**from the drop-down menu. Let’s make the sample size 100 and standard deviation 75. Mean stays 0. - Check the
**Raw Data**check-box on the left side – this step is the simplest yet most important. - Hit the
**Sample**button and click on the Data tab next to the Graphs tab. - Select all the data by holding
*Apple+A*for Macs or*Ctrl+A*for PC. Press the COPY button at the top. - Go back to the window with the
**HistogramChartDemo**. Click on the**DATA**tab and press the**PASTE**button on the left hand side of the screen. - Click on the
**MAPPING**tab, and click on**Add**when C1 is highlighted. Then click on**UPDATE_CHART**at the top. - Click on the
**GRAPH**tab and play around with the bin size at the bottom. Take a picture of the histogram you created by using the Print Screen command. Comment on the changes you see as you increase/decrease the bin size.

### Part 2: Probability

- Go to the SOCR Experiments. We’re going to do the Coin Die Experiment again, so select it from the drop-down menu.
- Set the distribution of both dice to skewed left (6 should have the most probability).
- Set p = 0.8 and run 100 trials. Count the number of 6’s and take a picture of the graph.
- Repeat Step 3 with p = 0.2. Make sure you take a picture.
- Change the distribution of only the green die to skewed right (6 should have the least probability), and repeat steps 3 and 4. You should comment on changes and have 4 pics.

### Step 3: Binomial Distribution

- Go to the SOCR Experiments. Select Binomial Coin Experiment.
- Make sure n=20 and p=0.50.
- Choose the Stop 10 option and press fast-forward. This will generate 10 simulations of 20 flips of the coin. Take a picture.
- Choose the Stop 100 option and press fast-forward. This will generate 100 simulations of 20 flips of the coin. Take a picture. Compare the histogram with the histogram from Step 3.
- Compare the histogram with the histogram of normal distribution.

### Step 4: Coin Toss

- This portion does not require you to do any calculations on SOCR.
**Without**using the equations of binomial distribution, solve the following problem: Let X equal the number of heads when you flip the coin 3 times. Calculate \(P(X \ge 2)\).

Translate this page: