Skript Flashcards
(97 cards)
How do we define “artificial intelligence”?- Def.
Intelligence exhibited by non-biological systems
Artificial General Intelligence (AGI))- Def.
Human-level AI. The computer would need to be able to integrate many capabilites
Narrow AI-Def.
Ability to accomplish a narrow & well-defined set of goals (Matching resume to open job positions)
Cognition-Def.
the mental action or process of acquiring knowledge and understanding through thoughts, experience, and the senses. The psychological result of perception and learning and reasoning
Neural Networks -Def.
trained using machine learning approaches form the basis of most attempts at conginitc computing
Neuromorphic hardware -Def
It is being worked on in parallel to purely software.
The largest artificial neutral netwworks may have ca. 200 layern=> size of a frog brain
Artificial intelligence => ML=> DL
[AI] Human intelligence exhibited by machines - terms for (narrow) use cases, includes any simulation of human intelligence => [ML] Computer can learn from data without being explicitly programmes - terms for the technology, Uses numerical and statistical approaches (pattern), Models are built using “training” computation runs, can also train through usage => [DL aka Neural Network] A subfield of ML that uses specialized computational techniques, typically multi-layer (2+) artifical neural network, layering allows cascaded learning and abstraction levels (e.g. line recognition -> shape -> object -> scene ), Computationally intensive enabled by clouds, GPU’s, and increasingly more specialized HW
AI is becoming feasible because of a conflux of several technological advancements. The field is advancing rapidly beyond mathematical proofs because researchers can experiment with data and methods:
Powerful hardware -GPUS/TPUs accelerated training time of DNNs
Digitization & Big data- e.g. IOT, Digital receipts, Technologies like SAP HANA
Cloud computing -access powerful hardware with an Internet connection and credit card
Advances in applied deep neutral networks- Deep learning, new statistical techniques
What are First AI Attempts?
Rules-based “expert systems”:
If-then-else rules or algorithms, highly logical, structures & explainable, use structured, codified data
What is probabilistic machine learning
learn from data without being explicitly programmed (Cat-dog example)
Summary and Key Takeaways
- Intelligence is the ability to achieve complex goals. AI is intelligence exhibited by non-biological systems
- Currently the most feasible approach to AI is machine learning -> learning from large amount of data without beeing programmed
- AI leverages many different statistical modeling approaches from simple regressions to deep learning networks. Many are years old. Rules-based expert systems are still a useful and valid approach
- Feasible today because of ..(you know)
- People are comfy with rules-based systems but less comfortable with probabilistic
- we all train machine learning models every day. Big advantage
Basic ML Workflow
Trainings Data->Learning Algorithm -> Model1
Testing Data->Model2Accuracy Estimated
Model2->Model3 Prediction
Machine Learning is bases on 3 different categories of approaches to learning:
Supervised learning:
We provice the machine with examples of the desired solutiom (most common)
Unsupervised Learning: Data is set unlabeled- machine finds pattern /strucutes, Evaluation is qualitative or indirect
Reinforcement learning: Intelligence agents learn a polivy given neither data nor labels, only rules in their environment, observes environment, performs actions, gets rewards/penalties, Not to be confused with retraining a supervides learning model
Supervised learning:
In supervised the training inputs and desired outputs (called “labels”) are given by a “teacher”
Unsupervised learning
No labels are given to the learning algorithm, leaving it on its own to find the structure (costumer segments)
Reinforcement learning
we don’t start with data, but rather a defined envorinment. The agent trains its own policy throgh a process of trial and error
Classes of problem AI can adress
- Predicition, Forecasting, PAttern detection
- Computer Vision & Sensory Information
- Natural Language Processing and Unstructed Text
Regression (supervised) Def.
The output (i.e. what the machine predicts) is continours rather than discrete. Many kinds of regression models exist e.g. Year an employee will stay with the company
Classification (supervised) Def.
The model assigns inputs into 2 or more discrete classes. Inputs are aaigned to call with a given confidence level-Most machine learning adresses classificaiton problems e.g. employee will churn or not?, customer will choose product A oder Product B (or C)
Clustering Def. (mostly unsupervised) Def.
Divide the inputs into groups. The group are normally not know beforehand, making this typicaly an unsupervised task. E.g Customer Segmentation, Genome squencing
Dimensionality Reduction Def.
Map from higher dimensinal features space to lower dimensions is uses to combine several highly similar features into a singel feature E.g combine several items on a survey into a single “construct” variable
Examples for Models and Tools of statistical Model
Classification Analysis, Regression, Cluster analysis, Time series analysis, Association analysis, probability Distribution, Outlier Detection, Recommender Systems, Link prediction, Statistical Functions, Data prepation
How do you do feature engineering?
Creation of categorical or dummy variables, data cleaning, feature normaliazation /scaling, handle missing values, standardize input format
Misconception: A machine learns immediately after every click
Correction: A model is updated after we retrain model using the entire data set from scratch. Small exceptions include trransfer learning and active learning