Lecture 1
Information science = investigates the properties and behaviour of information, the forces governing
the flow of information, and the means of processing information for optimum accessibility and
usability. It is concerned with the body of knowledge relating to the organization, collection,
organization, storage, retrieval, interpretation, transmission and utilization of information.
The Knowledge Hierarchy
DIKW Pyramid
- Data observations without context (not useful)
- Information observations with context (useful)
- Knowledge information that is selected and organized (more useful)
- Wisdom knowledge that is combined and integrated (super useful)
Types of knowledge
- Personal knowledge
o Knowledge of self
- Procedural knowledge
o Knowledge of how to do something
- Propositional knowledge
o Knowledge of facts about the world
Dangers related to (online) information
- Misinformation (incorrect information by accident)
- Disinformation (incorrect information on purpose)
- Hate speech
- Propaganda
- Filter bubbles
Evaluating information
- Better information leads to better decision making leads to a better world
o Who is behind this information
o What is the evidence for their claims
o What do other sources say
, Practical lecture 1
Information retrieval = finding material of an unstructured nature that satisfies an information need
from within large collections
Search engine = information retrieval system
Database search Search with search engine
Collections of highly structured information Searches the World Wide Web
Retrieved from a database using a structured Contains written text and multimedia, highly
query unstructured
Structured queries are expressed with special Accept natural language queries: no structure
“query languages” required
Information need = the abstract desire for information existing in the user’s own mind
The user expresses that information need as a query
Relevant item = an item (webpage, document, image, video) that satisfies the user’s information
need
The success of information retrieval systems and search engines is measured in terms of their
ability to return relevant items
Precision = relevant items retrieved / retrieved items (deel gedeeld door geheel)
Evaluation of Information Technology
- Qualitative evaluation
o Carrying out an evaluation that involves observation, but no numbers
o Discovering knowledge and formulating hypotheses for further study
- Quantitative evaluation
o Carrying out an evaluation that results in a score that can be used for comparison
o Systematic comparison using a very large number of examples
Intelligent information
- Spell checking
1. Identification = predict that the word is misspelled
o Spell checker uses a limited dictionary of known strings
o Word not in dictionary? – alleged misspelling
Issues with identification
o Spelling error is an existing word
o Word not in the dictionary
o Language of word different than language of sentence
o Non-alphanumeric characters are skipped
2. Correction = suggest the correct spelling of the word
o Assumption: misspellings are mutations of dictionary words
First: find strings similar to misspelling
Then: order them by similarity score
Finally: suggest word that is nearest to misspelling
Issues with correction
Information science = investigates the properties and behaviour of information, the forces governing
the flow of information, and the means of processing information for optimum accessibility and
usability. It is concerned with the body of knowledge relating to the organization, collection,
organization, storage, retrieval, interpretation, transmission and utilization of information.
The Knowledge Hierarchy
DIKW Pyramid
- Data observations without context (not useful)
- Information observations with context (useful)
- Knowledge information that is selected and organized (more useful)
- Wisdom knowledge that is combined and integrated (super useful)
Types of knowledge
- Personal knowledge
o Knowledge of self
- Procedural knowledge
o Knowledge of how to do something
- Propositional knowledge
o Knowledge of facts about the world
Dangers related to (online) information
- Misinformation (incorrect information by accident)
- Disinformation (incorrect information on purpose)
- Hate speech
- Propaganda
- Filter bubbles
Evaluating information
- Better information leads to better decision making leads to a better world
o Who is behind this information
o What is the evidence for their claims
o What do other sources say
, Practical lecture 1
Information retrieval = finding material of an unstructured nature that satisfies an information need
from within large collections
Search engine = information retrieval system
Database search Search with search engine
Collections of highly structured information Searches the World Wide Web
Retrieved from a database using a structured Contains written text and multimedia, highly
query unstructured
Structured queries are expressed with special Accept natural language queries: no structure
“query languages” required
Information need = the abstract desire for information existing in the user’s own mind
The user expresses that information need as a query
Relevant item = an item (webpage, document, image, video) that satisfies the user’s information
need
The success of information retrieval systems and search engines is measured in terms of their
ability to return relevant items
Precision = relevant items retrieved / retrieved items (deel gedeeld door geheel)
Evaluation of Information Technology
- Qualitative evaluation
o Carrying out an evaluation that involves observation, but no numbers
o Discovering knowledge and formulating hypotheses for further study
- Quantitative evaluation
o Carrying out an evaluation that results in a score that can be used for comparison
o Systematic comparison using a very large number of examples
Intelligent information
- Spell checking
1. Identification = predict that the word is misspelled
o Spell checker uses a limited dictionary of known strings
o Word not in dictionary? – alleged misspelling
Issues with identification
o Spelling error is an existing word
o Word not in the dictionary
o Language of word different than language of sentence
o Non-alphanumeric characters are skipped
2. Correction = suggest the correct spelling of the word
o Assumption: misspellings are mutations of dictionary words
First: find strings similar to misspelling
Then: order them by similarity score
Finally: suggest word that is nearest to misspelling
Issues with correction
