FW552
Applied Sampling

Class Stuff

  • Instructor: Brian Gerber

  • Classroom: Engineering E106

    • Lecture/Discussion/Problem Solving
  • When: Mo/We 3 - 4:15pm

  • My Office: 202A Wagar, Cooperative Research Unit

    • Office hours: We 1pm - 2pm and by appointment

    • brian.gerber@colostate.edu

  • Laptop: Needed for assignments and in class exercises.

My Background

What is this course?

Primarily:

  • connecting things we care about (fish/wildlife/habitat) with sampling principles

What is this course?

Main Objective:

  • to learn to think from a sampling perspective rather than a field logistics or field techniques perspective.

What is this course?

A mix of…

  • Sampling principles
  • Design-based inference
  • Math / notation
  • R coding

What is this course?

Some Important Concepts and Terminology

  • Inference

  • Sampling distribution

  • Sampling variation

  • Sampling bias

  • Sample size

  • Estimator bias and variance

Questions for you…

  • Name / Department

  • What does ‘Sampling’ mean to you?

  • Motivation for taking this course?

  • Experience with the R programming language

  • What is your ideal job, research project, study animal, or study location?

Assessment

Assessment Components Percentage of Grade
Course Engagement 10%
Assignments 25%
Quizzes 25%
Test 20%
Project 20%

Project

An oral presentation on a topic of choice that focuses on the ideas of sampling

  • how to improve a current project
  • designing a future study
  • evaluating sampling options in terms of bias/precision/cost/etc.

Why is this class useful?

  • Thinking from a sampling perspective is a super power!

  • Fundamental to scientific learning

  • Efficient learning about the world

  • Don’t need any damn statistical model!

  • Interpret and frame learning from any “study”

Software

Why learn to code?

  • efficiency
  • transparency
  • flexibility in application
  • shareable
  • marketable skill
  • needed for publications

Why use R?

  • open-source and free
  • small total user base / large in ecology and statistics
  • find help online, e.g., stackoverflow
  • data management
  • statistics
  • plotting / graphics

Why use RStudio?

Statistics in the Modern Age

"The theory and practice of computer-age statistics are, for the most part, a case of new wine in old bottles: The fundamental tenets of good statistical thinking have not changed, but their implementation has."
- Cox and Efron, Sci. Adv. 2017;3: e1700768.

Teaching Philosophy

  • Learning is a choice (in every moment)

  • Words Matter

  • An inclusive environment is paramount for learning

  • Communication is everything

  • Everyone has something to teach and something to learn

  • Struggle is good. Solving problems leads to learning. But….

Website

Most Material

https://bgerber123.github.io/FW552/


Quizzes and Assignments

https://canvas.colostate.edu/

Questions

A ‘Sample’

Brook trout habitat in rivers of Massachusetts

A finite part of a target population whose properties are studied to gain information about the whole (i.e., to infer or gain inference).

A ‘Sample’

Brook trout habitat in rivers of Massachusetts

A selection of rivers (sample) to measure habitat characteristics (e.g. gravel beds) to be used to infer about habitat in all of the state.

Not Sampling

Piping plovers nesting at Watch Hill, RI

Census: a complete enumeration of a target population

Sampling

The process of selecting a representative part of the population for the purpose of determining characteristics of the target population.

Why do we need to sample?

  • logistically/physically prohibitive
  • fiscally prohibitive / waste of time and money
  • timeliness
  • sampling may be destructive

Central paradox of sampling

  • Impossible to know whether a sample is ‘good’ (i.e., representative of the target)

  • The sample itself cannot tell us - only the process

  • Given exact same sample, we treat it differently depending on how it was selected.

  • A sample from a reliable process has credentials

How have you used sampling?