mean Archives - Infinity is Really Big

May 1, 2019January 11, 2020

Curtate Expectation of Life

Studying for Exam LTAM, Part 1.9

Image by Clker-Free-Vector-Images from Pixabay

Means of random variables can be thought of as centers of mass. If the random variable is continuous, think of the region under the graph of its probability density function (PDF) as a thin sheet of metal with constant density. The mean will be at the center of mass

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April 18, 2019April 23, 2019

Measures of Spread in Survival Models

Studying for Exam LTAM, Part 1.6

Image by Gerd Altmann from Pixabay

One of the main lessons students should get out of any statistics course is the fact that quantitative data can be described with summary measures.

Data come with a wide variety of “locations”, “spreads”, and “shapes”. These words refer to the nature of the distribution of a … Read the rest

April 4, 2019April 23, 2019

The Complete Expectation of Life

Studying for Exam LTAM, Part 1.3

Image by Susanne Pälmer from Pixabay

What is your life expectancy? Are you a smoker? A heavy drinker? Male or Female? And how well do you eat and exercise?

These factors can all affect how long you can “expect” to live.

However, the word “expect” can be misleading in this context. It is an … Read the rest

April 1, 2019April 23, 2019

Families of Continuous Survival Random Variables

Studying for Exam LTAM, Part 1.1

Photo by Nick Morrison on Unsplash

Where do we begin? Assuming the reader’s knowledge of the fundamentals of (calculus-based) probability theory, the best place to start is with continuous survival models. This is also a common initial chapter in the textbooks on the subject.

As I mentioned in the post “Studying for Exam … Read the rest