part 1 Flashcards
AI define
Machines performing jobs mimicking human behaviour
ML define
Foundation of an AI system, learns and predicts like a human
Machines that get better without explicit programming
DL define
Machines that have an artificial NN inspired by the human brain to solve complex problems
Data scientist define
Person with multi-disciplinary skills in maths, stats, predictive modelling and ML to make future predictions
Describe onion diagram of AI, ML, DL
AI contains ML which contains DL
Anomoly detection
Detects outliers or things out of place like a human
Computer vision
be able to see like a human
NLP
Be able to process human languages and infer context
Conversational AI
be able to hold a conversation with a human
What is a dataset
Logical grouping of units of data that are closely related and/or share the same data structure
MNIST
Images of handwritten digits used to test classification, clustering and image processing algorithms e.g. computer vision ML models
COCO (common objects in context) dataset
Contains common images using a JSON file (coco format) that identify objects or segments within an image
- features object segmentation, recognision in context, superpixel stuff segmentation
Azure has a data labelling service which can export in coco format
Data labeling
Identifying raw data and adding one more more meaningful and informative labels to provide context so ML model can learn
data labelling - supervised
Labels are a prerequisite to produce training data. Each piece generally labelled by a human
data labelling - unsupervised
Labels produced by machine, might not be human readable
ground truth
Properly labelled dataset used as objective standard to train and assess the model. Accuracy of trained model depends on accuracy of ground truth
Supervised learning
Data that has been labelled for training.
Task-driven - make a prediction
When the labels are known and you want a precise outcome. You need a specific value returned e.g. Classification, Regression
Unsupervised learning
Data has not been labelled, ML model needs to do its own labelling
Data-driven - recognise a structure or pattern
When labels not known and outcome doesn’t need to be precise.
Trying to make sense of data.
e.g. Clustering, dimensionality reduction, association
Reinforcement learning
No data, there is an environment and an ML model generates data any many times to reach a goal
Decisions-driven - Game AI, Learning Tasks, Robot Navigation
Neural network
Mimicking the brain. Node/neuron represents an algorithm
Data inputted into neuron and based on output, data passed to one of many other connected neurons.
Connections are weighted.
Network is organised into layers
Input layer, many hidden, and an output
How many layers for a NN to be called deep learning
3+
Feed Forward (FNN)
Neural networks where connections between nodes don’t form a cycle (always moving forward)
Back propagation
Moves backwards through the neural network adjusting weights to improve next iteration’s performance. How the Neural net learns.
Loss function
Function comparing ground truth to prediction to determine error rate. Performs calculation at the end, performs calculation and then back propagates.
Activation functions
Algorithm applied to a hidden layer node that affects connected output (e.g. ReLu, part of backpropagation)
Dense
When the next layer increases the number of nodes