# 1 Introduction to data, variation, and distributions

In this unit, you will learn about data, and the fundamental idea behind statistics: **data have variation.**

Because data vary, a data set is *distributed* across a range of values. A distribution is the primary object that statisticians work with. You will learn how to describe and summarize distributions, including summarizing the “typical” value of a distribution and quantifying the variation in a distribution. Together, these help us determine the *likely values* in a distribution.

Finally, you will learn how to summarize the ways in which the distribution of one variable may be associated with another.

### Outline and goals of Unit 1

The following schematic outlines the course readings and in-class activities for Unit 1.

Unit outline |
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1.1 🔨 Truck braking |

1.2 📖 Variation, variables, and distributions |

1.3 🔨 Describing distributions |

1.4 📖 Describing distributions |

1.5 🔨 Football kicking contest |

1.6 📖 The mean and standard deviation |

1.7 🔨 Statsical association |

1.8 📖 Statistical association |

1.9 📖 Linear regression |

1.10 🔨 Review activity: Happiness |

1.11 📖 Unit 1 summary |