# SOCR Courses 2012 2013 Stat13 1 Lab3b

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## 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

1. 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.
2. Open up another window (or another tab in the same browser window), go to the SOCR Modeler, and click on the Data Generation button.
3. Choose the Normal Distribution from the drop-down menu. Let’s make the sample size 100 and standard deviation 75. Mean stays 0.
4. Check the Raw Data check-box on the left side – this step is the simplest yet most important.
5. Hit the Sample button and click on the Data tab next to the Graphs tab.
6. Select all the data by holding Apple+A for Macs or Ctrl+A for PC. Press the COPY button at the top.
7. 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.
8. Click on the MAPPING tab, and click on Add when C1 is highlighted. Then click on UPDATE_CHART at the top.
9. 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

1. Go to the SOCR Experiments. We’re going to do the Coin Die Experiment again, so select it from the drop-down menu.
2. Set the distribution of both dice to skewed left (6 should have the most probability).
3. Set p = 0.8 and run 100 trials. Count the number of 6’s and take a picture of the graph.
4. Repeat Step 3 with p = 0.2. Make sure you take a picture.
5. 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

1. Go to the SOCR Experiments. Select Binomial Coin Experiment.
2. Make sure n=20 and p=0.50.
3. Choose the Stop 10 option and press fast-forward. This will generate 10 simulations of 20 flips of the coin. Take a picture.
4. 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.
5. Compare the histogram with the histogram of normal distribution.

### Step 4: Coin Toss

1. This portion does not require you to do any calculations on SOCR.
2. 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 $P(X \ge 2)$.