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📚 Python for Introductory Statistics: Lab Workbook
Chapters ▾
1. Introduction to Python2. Python List3. Python Syntax4. Python Loops5. Frequency Distributions and Graphs6. Measure of Center and Variation7. Measures of Position8 Discrete Probability Distributions9. Continuous Probability DistributionConfidence Intervals11. Hypothesis Testing12. Linear Regression and Correlation13. Analysis of Categorical Data14. Advanced Statistics TopicsLab AnswersReferencesAppendix 1Appendix 2: Random Integer GeneratorAppendix 3: FactorialsResources

8.1 Expected Value and Standard Deviation

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Lab 8.1.1

The random variable X is defined as the number of times a graduating senior changed majors. The probability distribution of X is given below.

| | | | | | | | | | | | |-|-|-|-|-|-|-|-|-|-|-| |x| 0|1 |2 |3 |4 |5 |6 |7 |8 |p(x) |0.197 |0.212 |0.255 |0.182 |0.09 |0.04 |0.02 |0.003 |0.001

  1. What is the mean number of times students changed majors?
  2. What is the standard deviation of X?

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Adapted from Python for Introductory Statistics: Student's Lab Workbook, by Simon Aman (Truman College, City Colleges of Chicago), licensed under CC BY 4.0. Changes were made: reformatted as an accessible XYZ web edition with live in-browser code cells. License: CC-BY-4.0.