2A: Errors and Biases

Measurement

Trying to get a property of something; always made using an INSTRUMENT, always has magnitude and unit

Uncertainty of Measurement

Doubt that exists about result of any measurement; ALWAYS exists because measurements are never 100%

Error

QUANTIFIED DIFFERENCE between observed values and true info

Accuracy

TRUENESS of an answer/measure

Precision

Spread of data; can be guaranteed (important b/c repetition and falsifiability)

Error Types

1) Random/Indetermined (unpredictable, experimental conditions, judgement, etc.; effects precision) 2) Systematic Error (constant and repeatable, all measurements shift) 3) Gross Errors (human mistakes, invalidate experiment --> start over)

Standard Deviation

Assesses spread of data

Bias

Skews interpretation/data; peer review is the best way to mitigate it

Confirmation Bias

Reinforces Beliefs

Hindsight Bias

"I Knew it" --> overestimates ability to predict

Anchoring Bias

Influenced by the first thing you see

Misinformation Effect

Memories are influenced by things that happened after

Actor-Observer Bias

Idea that your actions are because of external factors, while others are internal

False-Consensus

Tendency to overestimate popularity of beliefs

Halo effect

Initial impression = our overall belief, "attractiveness effect"

Apophenia

Tendency to see patterns when there are none