E1 Flashcards
Regression
Attempts to estimate or predict the numerical value of some variable for an individual (e.g. price of Microsoft stock).
Classification
Attempts to predict which of a (small) set of classes an individual belong to.
Usually classes are mutually exclusive (e.g. customers will churn or will not churn).
Regression Mathematical Formula / Rule-based Formula
Mathematical Formula
- Linear Regression
- Logistic Regression
Rule-based Formula
- Regression Trees
Classification Mathematical Formula / Rule-based Formula
Mathematical Formula
- Logistic Regression
- Support Vector Machines
Rule-based Formula
- Classification Trees
Stages of a predictive modeling process
- Define target
- Collect data
- Build a model
- Predict outcomes
- Define target
It has to be a quantifiable target.
a. E.g. what will be the stock price of Microsoft tomorrow? 200
b. E.g. will this client default on her loan? -> not specific enough! You want a time frame such as ‘first five years’ (though it depends on what you want to know)
- Collect data
We need data for the same or a related phenomenon
a. E.g. which customers defaulted last quarter? Think about whether or not this is the same phenomenon. Look at stuff that has happened in the past.
- Build a model
The model will look like a set of rules or a mathematical formula that allow establishing a prediction
a. E.g. rule: if (income <50k) then default, else no default.
b. E.g. mathematical formula: MSFTt+1 = 0.9 – APPLt -> predictive stock market value of Microsoft will be 90% of Apple’s.
- Predict outcomes
The model can be applied to any customer. It gives us a prediction of the target variable.
a. E.g. the customer will default because its income is lower than 50k.
b. E.g. MSFT = $212.