# [[Variables ]]
### Type of data variable contains
- **Quantitative Variables** representing Amounts
- Discrete aka Integer Variables
- individual items or values
- eg. no. of students in a class
- Continuous aka Ratio Variables
- Measurement of continuous or non-finite values
- eg. Distance
- **Categorical Variables** representing Groupings
- Binary variables
- yes / no outcomes
- eg. heads or tails / win or lose
- Nominal variables
- Groups with no rank or volume
- eg. colours, species names
- Ordinal variables
- Groups ranked in a specific order
- eg. race standings
#### Part of the problem it represents
- **Independent Variables** the cause
- Treatment variables
- manipulate in order to affect the outcome of an experiment
- eg. salt you add to plants water to impact growth
- **Dependent Variables** the effect
- Response variables
- represent the outcome of the experiment
- eg. any measurement of plant health and growth
- **Control Variables** constants
- Constant variables
- held constant throughout the experiment
- eg. temperature and light
##### Other
- **Confounding Variables**
- Hides the true effect of another variable in your experiment
- potentially hold them constant
- eg. pot size and soil type
- **Latent Variables**
- can’t be directly measured, but that you represent via a proxy
- could be inferred / observed
- eg. Salt tolerance
- **Composite Variables**
- made by combining multiple variables in an experiment
- created when analyzing not measuring data
- eg. plant health score
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Tags: #tech
Links: [[Problem Formulations]]