What, how, why of stats Flashcards
What is statistics?
A piece of info (data) that can be represented numerically
How do you do stats?
Is a particular branch of applied math that collects data and uses probability theory to draw conclusions from that data
Why would we do stats?
To understand the real meaning behind all those numbers
What is NOT the point of doing stats? What is the actual point then?
To decide if an effect is statistically significant. The real point is to quantify scientific evidence and uncertainty
What are the two key words about why we do stats?
Understanding and prediction
Why are stats and probability not intuitive?
We need evidence. Can’t just draw conclusions from a bunch of numbers without stats
What 7 things do us humans tend to do thinking stats and probability are intuitive?
- Jump to conclusions based on what we know
- Be overconfident in something, thinking we’re smarter than we are
- See patterns in data when it’s just random
- Not linking variability to sample size
- Fooled by multiple comparisons
- Ignoring any alternate explanations like biases and placebos
- Crave crisp defined conclusions when they’re mostly just probabilities
What are the 4 goals of stats?
- Estimate values of important parameters
- Test hypotheses about those parameters
- For good scientific practice
- Quantify the uncertainty of measurements
What is the definition of stats?
A technology that describes and measures aspects of nature using samples
What are 4 challenges of doing stats?
- No two individuals are exactly alike
- Unfeasible to measure an entire population
- Sampling leads to uncertainty
- Measurements can be affected by sampling
What is estimation?
Inferring an unknown quantity of a target population based on sample data
Are estimations made with data from samples or from the population?
Samples
What is a parameter?
A quantity that describes a population
What are 4 types of parameters?
Averages, proportions, measures of variation (SD and SE), measures of relationship
How do we estimate a population parameter?
Use measurements from a sample to best estimate parameters
