Crash Course - Statistics

Author

Beniamino Sartini

Published

September 24, 2025

Summary

General notations

  • Ω abstract set representing the sample space of a random experiment. The elements in ωΩ are the possible outcomes of the experiment.
  • P(Ω): power set of Ω, the set of all possible subsets of Ω.
  • Most of subsets A,B, will be thought as events.
  • Collection of subsets A,B,.
  • The empty set .
  • B is a σ-field, usually connected with the sample space Ω.
  • B(R) is the Borel σ-field of R.
  • P is a probability measure function P:B[0,1].
  • (Ω,B,P) is a probability space.
  • is a shortcut to denote a disjoint union, for example writing AB means that the sets A and B are disjoint, while writing AB means that the sets A and B are not disjoint.
  • X denotes an univariate random variable.
  • Bold letters, Xn=(X1,X2,,Xi,,Xn) denotes a random vector with n elements, where each Xi is a random variable. Instead, xn=(x1,x2,,xi,,xn) denotes a vector, where each xi is a scalar.
  • X denotes a random matrix. More precisely, X=(X1,X2,,Xj,,Xk), where Xj is a random vector related to the column j with n-elements. In matrix context, the index i denotes a generic row, while j a generic column.

Syllabus