Week 7 + 8: Machine Learning Flashcards
What is machine learning
learning from data without previous programming used to discover hidden patterns/trends enables data driven decisions
4 categories of machine learning
- Classification
- Regression
- Clustering
- Association analysis
Classification is used to predict a…
category
Regression is used to predict a…
numeric value
Cluster analysis is used to
organise simliar items into groups eg customers
Association analysis is used to…
capture assocations between items or events
Name 2 supervised machine learning techniques
- Classification
- Regression
Name 2 unsupervised machine learning techniques
- Clustering
- Association analysis
What is supervised machine learning
Where you have input variables an output variable using an algorithm to learn the mapping function between the input and the output
4 examples of supervised machine learning algorithms
- KNN
- Decision tree
- Linear Regression
- SVM (Support vector machines)
What is unsupervised machine learning? It is where you only have…
input data and not corresponding output variables
What is the goal of unsupervised machine learning?
To model the underlying structure or distribution in the data
2 examples of unsupervised machine learning algorithma
- k-means clustering
- apriori for association analysis
kNN is used to
classify a sample based on its neighbors
What is k in kNN? The value of k determines…
the number of nearest neighbors to consider
kNN 4 distance metrics
- Euclidean Distance
- City Block Distance
- Chi square distance
- Cosine distance
2 pros of kNN
- No separate training phase
- Can generate complex decision boundaries
2 cons of kNN
- Can be susceptible to noise
- Can be slow, since distance is recalculated each time