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06/26/22 Data Mining: Principles and A lgorithms 1 Data Mining: Principles and Algorithms — Chapter 10.1 — — Mining Object, Spatial, and Multimedia Data— ©Jiawei Han Department of Computer Science University of Illinois at Urbana-Champaign www.cs.uiuc.edu/~hanj

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04/10/23 Data Mining: Principles and Algorithms

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Data Mining: Principles and Algorithms

— Chapter 10.1 —

— Mining Object, Spatial, and Multimedia Data—

©Jiawei Han

Department of Computer Science

University of Illinois at Urbana-Champaign

www.cs.uiuc.edu/~hanj

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Mining Object, Spatial and Multi-Media Data

Mining object data sets

Mining spatial databases and data warehouses

Spatial DBMS

Spatial Data Warehousing

Spatial Data Mining

Spatiotemporal Data Mining

Mining multimedia data

Summary

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Mining Complex Data Objects: Generalization of Structured Data

Set-valued attribute

Generalization of each value in the set into its

corresponding higher-level concepts

Derivation of the general behavior of the set, such as the

number of elements in the set, the types or value ranges

in the set, or the weighted average for numerical data

E.g., hobby = {tennis, hockey, chess, violin, PC_games}

generalizes to {sports, music, e_games}

List-valued or a sequence-valued attribute

Same as set-valued attributes except that the order of the

elements in the sequence should be observed in the

generalization

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Generalizing Spatial and Multimedia Data

Spatial data: Generalize detailed geographic points into clustered

regions, such as business, residential, industrial, or agricultural areas, according to land usage

Require the merge of a set of geographic areas by spatial operations

Image data: Extracted by aggregation and/or approximation Size, color, shape, texture, orientation, and relative

positions and structures of the contained objects or regions in the image

Music data: Summarize its melody: based on the approximate patterns

that repeatedly occur in the segment Summarized its style: based on its tone, tempo, or the

major musical instruments played

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Generalizing Object Data Object identifier

generalize to the lowest level of class in the class/subclass hierarchies

Class composition hierarchies generalize only those closely related in semantics to the

current one Construction and mining of object cubes

Extend the attribute-oriented induction method Apply a sequence of class-based generalization operators on

different attributes Continue until getting a small number of generalized objects

that can be summarized as a concise in high-level terms Implementation

Examine each attribute, generalize it to simple-valued data Construct a multidimensional data cube (object cube) Problem: it is not always desirable to generalize a set of

values to single-valued data

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Ex.: Plan Mining by Divide and Conquer

Plan: a sequence of actions E.g., Travel (flight): <traveler, departure, arrival, d-time, a-

time, airline, price, seat> Plan mining: extraction of important or significant generalized

(sequential) patterns from a planbase (a large collection of plans)

E.g., Discover travel patterns in an air flight database, or find significant patterns from the sequences of actions in the

repair of automobiles Method

Attribute-oriented induction on sequence data A generalized travel plan: <small-big*-small>

Divide & conquer:Mine characteristics for each subsequence E.g., big*: same airline, small-big: nearby region

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A Travel Database for Plan Mining

Example: Mining a travel planbase

plan# action# departure depart_time arrival arrival_time airline …1 1 ALB 800 JFK 900 TWA …1 2 JFK 1000 ORD 1230 UA …1 3 ORD 1300 LAX 1600 UA …1 4 LAX 1710 SAN 1800 DAL …2 1 SPI 900 ORD 950 AA …. . . . . . . .. . . . . . . .. . . . . . . .

airport_code city state region airport_size …1 1 ALB 800 …1 2 JFK 1000 …1 3 ORD 1300 …1 4 LAX 1710 …2 1 SPI 900 …. . . . .. . . . .. . . . .

Travel plan table

Airport info table

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Multidimensional Analysis

Strategy Generalize the

planbase in different directions

Look for sequential patterns in the generalized plans

Derive high-level plans

A multi-D model for the planbase

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Multidimensional Generalization

Plan# Loc_Seq Size_Seq State_Seq

1 ALB - JFK - ORD - LAX - SAN S - L - L - L - S N - N - I - C - C2 SPI - ORD - JFK - SYR S - L - L - S I - I - N - N. . .. . .. . .

Multi-Dimensional generalization of the planbase

Plan# Size_Seq State_Seq Region_Seq …1 S - L+ - S N+ - I - C+ E+ - M - P+ …2 S - L+ - S I+ - N+ M+ - E+ …. . .. . .. . .

Merging consecutive, identical actions in plans

%]75[)()(

),(_),(_),,(

yregionxregion

LysizeairportSxsizeairportyxflight

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Generalization-Based Sequence Mining

Generalize planbase in multidimensional way using dimension tables

Use # of distinct values (cardinality) at each level to determine the right level of generalization (level-“planning”)

Use operators merge “+”, option “[]” to further generalize patterns

Retain patterns with significant support

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Generalized Sequence Patterns

AirportSize-sequence survives the min threshold (after applying merge operator):

S-L+-S [35%], L+-S [30%], S-L+ [24.5%], L+ [9%] After applying option operator:

[S]-L+-[S] [98.5%] Most of the time, people fly via large airports to

get to final destination Other plans: 1.5% of chances, there are other

patterns: S-S, L-S-L

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Mining Object, Spatial and Multi-Media Data

Mining object data sets

Mining spatial databases and data warehouses

Spatial DBMS

Spatial Data Warehousing

Spatial Data Mining

Spatiotemporal Data Mining

Mining multimedia data

Summary

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What Is a Spatial Database System?

Geometric, geographic or spatial data: space-related data

Example: Geographic space (2-D abstraction of earth

surface), VLSI design, model of human brain, 3-D space

representing the arrangement of chains of protein

molecule.

Spatial database system vs. image database systems.

Image database system: handling digital raster image (e.g.,

satellite sensing, computer tomography), may also contain

techniques for object analysis and extraction from images

and some spatial database functionality.

Spatial (geometric, geographic) database system: handling

objects in space that have identity and well-defined

extents, locations, and relationships.

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GIS (Geographic Information System)

GIS (Geographic Information System)

Analysis and visualization of geographic data

Common analysis functions of GIS

Search (thematic search, search by region)

Location analysis (buffer, corridor, overlay)

Terrain analysis (slope/aspect, drainage network)

Flow analysis (connectivity, shortest path)

Distribution (nearest neighbor, proximity, change detection)

Spatial analysis/statistics (pattern, centrality, similarity, topology)

Measurements (distance, perimeter, shape, adjacency, direction)

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Spatial DBMS (SDBMS)

SDBMS is a software system that supports spatial data models, spatial ADTs, and a query language supporting them supports spatial indexing, spatial operations efficiently, and query optimization can work with an underlying DBMS

Examples Oracle Spatial Data Catridge ESRI Spatial Data Engine

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Modeling Spatial Objects

What needs to be represented?

Two important alternative views

Single objects: distinct entities arranged in

space each of which has its own geometric

description

modeling cities, forests, rivers

Spatially related collection of objects: describe

space itself (about every point in space)

modeling land use, partition of a country into

districts

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Modeling Single Objects: Point, Line and Region

Point: location only but not extent

Line (or a curve usually represented by a polyline, a

sequence of line segment):

moving through space, or connections in space

(roads, rivers, cables, etc.)

Region:

Something having extent in 2D-space (country,

lake, park). It may have a hole or consist of

several disjoint pieces.

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Modeling Spatially Related Collection of Objects

Modeling spatially related collection of objects: plane partitions

and networks.

A partition: a set of region objects that are required to be

disjoint (e.g., a thematic map). There exist often pairs of

objects with a common boundary (adjacency relationship).

A network: a graph embedded into the plane, consisting of a

set of point objects, forming its nodes, and a set of line

objects describing the geometry of the edges, e.g.,

highways. rivers, power supply lines.

Other interested spatially related collection of objects:

nested partitions, or a digital terrain (elevation) model.

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Spatial Data Types and Models

Field-based model: raster data

framework: partitioning of space

Object-based model: vector model

point, line, polygon, Objects, Attributes

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Spatial Query Language Spatial query language

Spatial data types, e.g. point, line segment, polygon, … Spatial operations, e.g. overlap, distance, nearest neighbor, … Callable from a query language (e.g. SQL3) of underlying DBMS

SELECT S.nameFROM Senator SWHERE S.district.Area() > 300

Standards SQL3 (a.k.a. SQL 1999) is a standard for query languages OGIS is a standard for spatial data types and operators Both standards enjoy wide support in industry

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Spatial Data Types by OGIS

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Query Processing

Efficient algorithms to answer spatial queries Common Strategy: filter and refine

Filter: Query Region overlaps with MBRs (minimum bounding rectangles) of B, C, D Refine: Query Region overlaps with B, C

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Join Query Processing

Determining Intersection Rectangle Plane Sweep Algorithm

Place sweep filter identifies 5 intersections for refinement step

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File Organization and Indices

SDBMS: Dataset is in the secondary storage, e.g. disk Space Filling Curves: An ordering on the locations in a multi-dimensional space

Linearize a multi-dimensional space Helps search efficiently

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File Organization and Indices

Spatial Indexing B-tree works on spatial data with space filling curve R-tree: Heighted balanced extention of B+ tree

Objects are represented as MBR provides better performance

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Spatial Query Optimization

A spatial operation can be processed using

different strategies

Computation cost of each strategy depends on

many parameters

Query optimization is the process of

ordering operations in a query and

selecting efficient strategy for each operation

based on the details of a given dataset

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Spatial Data Warehousing

Spatial data warehouse: Integrated, subject-oriented, time-variant,

and nonvolatile spatial data repository

Spatial data integration: a big issue

Structure-specific formats (raster- vs. vector-based, OO vs.

relational models, different storage and indexing, etc.)

Vendor-specific formats (ESRI, MapInfo, Integraph, IDRISI, etc.)

Geo-specific formats (geographic vs. equal area projection, etc.)

Spatial data cube: multidimensional spatial database

Both dimensions and measures may contain spatial components

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Dimensions and Measures in Spatial Data Warehouse

Dimensions non-spatial

e.g. “25-30 degrees” generalizes to“hot” (both are strings)

spatial-to-nonspatial e.g. Seattle generalizes

to description “Pacific Northwest” (as a string)

spatial-to-spatial e.g. Seattle generalizes

to Pacific Northwest (as a spatial region)

Measures numerical (e.g. monthly

revenue of a region) distributive (e.g. count,

sum) algebraic (e.g. average) holistic (e.g. median, rank)

spatial collection of spatial

pointers (e.g. pointers to all regions with temperature of 25-30 degrees in July)

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Spatial-to-Spatial Generalization

Generalize detailed geographic points into clustered regions, such as businesses, residential, industrial, or agricultural areas, according to land usage

Requires the merging of a set of geographic areas by spatial operations

Dissolve

Merge

Clip

Intersect

Union

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Example: British Columbia Weather Pattern Analysis

Input A map with about 3,000 weather probes scattered in B.C. Daily data for temperature, precipitation, wind velocity,

etc. Data warehouse using star schema

Output A map that reveals patterns: merged (similar) regions

Goals Interactive analysis (drill-down, slice, dice, pivot, roll-up) Fast response time Minimizing storage space used

Challenge A merged region may contain hundreds of “primitive”

regions (polygons)

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Star Schema of the BC Weather Warehouse

Spatial data warehouse Dimensions

region_name time temperature precipitation

Measurements region_map area count

Fact tableDimension table

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Dynamic Merging of Spatial Objects

Materializing (precomputing) all?—too much storage space

On-line merge?—slow, expensive Precompute rough approximations?—

accuracy trade off A better way: object-based, selective

(partial) materialization

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Methods for Computing Spatial Data Cubes

On-line aggregation: collect and store pointers to spatial objects in a spatial data cube expensive and slow, need efficient aggregation

techniques Precompute and store all the possible combinations

huge space overhead Precompute and store rough approximations in a

spatial data cube accuracy trade-off

Selective computation: only materialize those which will be accessed frequently a reasonable choice

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Spatial Association Analysis

Spatial association rule:A B [s%, c%] A and B are sets of spatial or non-spatial predicates

Topological relations: intersects, overlaps, disjoint, etc. Spatial orientations: left_of, west_of, under, etc. Distance information: close_to, within_distance, etc.

s% is the support and c% is the confidence of the rule

Examples1) is_a(x, large_town) ^ intersect(x, highway) adjacent_to(x,

water)

[7%, 85%]

2) What kinds of objects are typically located close to golf courses?

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Progressive Refinement Mining of Spatial Association Rules

Hierarchy of spatial relationship: g_close_to: near_by, touch, intersect, contain, etc. First search for rough relationship and then refine it

Two-step mining of spatial association: Step 1: Rough spatial computation (as a filter)

Using MBR or R-tree for rough estimation Step2: Detailed spatial algorithm (as refinement)

Apply only to those objects which have passed the rough spatial association test (no less than min_support)

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Mining Spatial Co-location Rules

Co-location rule is similar to association rule but

explore more relying spatial auto-correlation

It leads to efficient processing

It can be integrated with progressive refinement

to further improve its performance

Spatial co-location mining idea can be applied to

clustering, classification, outlier analysis and

other potential mining tasks

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Spatial Autocorrelation

Spatial data tends to be highly self-correlated

Example: Neighborhood, Temperature

Items in a traditional data are independent of

each other, whereas properties of locations in a

map are often “auto-correlated”.

First law of geography:

“Everything is related to everything, but nearby

things are more related than distant things.”

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Spatial Autocorrelation (cont’d)

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Methods in classification Decision-tree classification, Naïve-Bayesian

classifier + boosting, neural network, logistic regression, etc.

Association-based multi-dimensional classification - Example: classifying house value based on proximity to lakes, highways, mountains, etc.

Assuming learning samples are independent of each other Spatial auto-correlation violates this assumption!

Popular spatial classification methods Spatial auto-regression (SAR) Markov random field (MRF)

Spatial Classification

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Spatial Auto-Regression

Linear Regression

Y=X +

Spatial autoregressive regression (SAR)

Y = WY + X + W: neighborhood matrix.

models strength of spatial dependencies

error vector

The estimates of and can be derived using

maximum likelihood theory or Bayesian statistics

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Markov Random Field Based Bayesian Classifiers

Bayesian classifiers

MRF A set of random variables whose interdependency

relationship is represented by an undirected graph (i.e., a symmetric neighborhood matrix) is called a Markov Random Field.

Li denotes set of labels in the neighborhood of si excluding labels at si

Pr(Ci | Li) can be estimated from training data by examine the ratios of the frequencies of class labels to the total number of locations

Pr(X|Ci, Li) can be estimated using kernel functions from the observed values in the training dataset

(X) Pr

Li) | Pr(Ci Li) Ci,|Pr(X Li) X, | Pr(Ci

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SAR v.s. MRF

Li) | Pr(Ci ,Li) Ci,|Pr(X

Li) | Pr(Ci ,Li) Ci,|Pr(X

Li) X,|Pr(Ci

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Function

Detect changes and trends along a spatial

dimension

Study the trend of non-spatial or spatial data

changing with space

Application examples

Observe the trend of changes of the climate or

vegetation with increasing distance from an ocean

Crime rate or unemployment rate change with

regard to city geo-distribution

Spatial Trend Analysis

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Spatial Cluster Analysis

Mining clusters—k-means, k-medoids, hierarchical, density-based, etc.

Analysis of distinct features of the clusters

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Constraints-Based Clustering

Constraints on individual objects Simple selection of relevant objects before

clustering

Clustering parameters as constraints K-means, density-based: radius, min-# of points

Constraints specified on clusters using SQL aggregates Sum of the profits in each cluster > $1 million

Constraints imposed by physical obstacles Clustering with obstructed distance

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Constrained Clustering: Planning ATM Locations

Mountain

RiverBridge

Spatial data with obstacles

C1

C2C3

C4

Clustering without takingobstacles into consideration

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Spatial Outlier Detection

Outlier Global outliers: Observations which is inconsistent

with the rest of the data Spatial outliers: A local instability of non-spatial

attributes Spatial outlier detection

Graphical tests Variogram clouds Moran scatterplots

Quantitative tests Scatterplots Spatial Statistic Z(S(x))

Quantitative tests are more accurate than Graphical tests

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Spatial Outlier Detection─Variogram Clouds

Graphical method For each pair of locations,

the square-root of the absolute difference between attribute values at the locations versus the Euclidean distance between the locations are plotted

Nearby locations with large attribute difference indicate a spatial outlier

Quantitative method Compute spatial statistic

Z(S(x))

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Spatial Outlier Detection—Moran Scatterplots

Graphical tests A plot of normalized

attribute value Z against the neighborhood average of normalized attribute values (W•Z)

The upper left and lower right quadrants indicate a spatial outlier

Computation method Fit a linear regression line Select points (e.g. P, Q, S)

which are from the regression line greater than specified residual error

f

fuififZ

)(

)]([

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Mining Spatiotemporal Data

Spatiotemporal data Data has spatial extensions and changes

with time Ex: Forest fire, moving objects, hurricane

& earthquakes Automatic anomaly detection in massive

moving objects Moving objects are ubiquitous: GPS,

radar, etc. Ex: Maritime vessel surveillance Problem: Automatic anomaly detection

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Analysis: Mining Anomaly in Moving Objects

Raw analysis of collected data does not fully convey “anomaly” information

More effective analysis relies on higher semantic features

Examples: A speed boat moving quickly in open water A fishing boat moving slowly into the docks A yacht circling slowly around landmark

during night hours

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Framework: Motif-Based Feature Analysis

Motif-based representation A motif is a prototypical movement pattern View a movement path as a sequence of

motif expressions Motif-oriented feature space

Automated motif feature extraction Semantic-level features

Classification Anomaly detection via classification High dimensional classifier

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Movement Motifs

Prototypical movement of object Right-turn, U-turn

Can be either defined by an expert or discovered automatically from data Defined in our

framework Extracted in movement

paths Path becomes a set of

motif expressions

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Motif Expression Attributes

Each motif expression has attributes (e.g., speed, location, size)

Attributes express how a motif was expressed

Conveys semantic information useful for classification a tight circle at

30mph near landmark Y.

A tight circle at 10mph in location X

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Motif-Oriented Feature Space

Attributes describe how motifs are expressed

Let there be A attributes, each path is a set of (A+1)-tuples

{(mi, v1, v2, …, vA), (mj, v1, v2, …, vA)} Naïve Feature space construction

n Let each distinct (mj, v1, v2, …, vA) be a feature

n If path exhibits a particular motif-expression, its value is 1. Otherwise, its value is 0.

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Analyzing Naïve Feature Space

Let there be M distinct motifs and V different possible values for each of the A attributes

Size of feature space is

M * VA

V is usually very large due to high granularity of measurements E.g., seconds for time or meters for location

Modest values for A and M could lead to extremely high dimensional feature space

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More on Naïve Feature Space

High dimensional feature space could make effective learning hard

More importantly, high granular features make generalization impossible! (mj, v1, 10:01am, …, vA) vs (mj, v1, 10:02am, …, vA) Learning on one feature has no effect on another

feature Intuition: should have features that describe

general high-level concepts “Early Morning” instead of 2:03am, 2:04am, … “Near Location X” instead of “50m west of Location

X” Solution: Clustering on naïve feature space

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Motif Feature Extraction

For each motif attribute, cluster values to form higher level concepts

Frequency and distribution in learning data dictates the final clusters

Hierarchical micro-clustering Small clusters so concepts are not

merged unnecessarily Hierarchy allows flexibility in describing

objects For example: “afternoon” vs. “early

afternoon” and “late afternoon”

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Feature Clustering

Rough, fast micro-clustering method based on BIRCH (SIGMOD’96)

A micro-cluster is represented by a CF Vector: CF = (n, LS, SS)

Centroid and radius can be calculated from CF vector CF Additive Theorem allows two CF Vectors to be

combined quickly and losslessly CF Tree is a hierarchy of CF Vectors

A parent CF Vector holds information for all descendent CF Vectors

Leaf CF Vector corresponds to a set of actual points

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More on Feature Clustering

Build CF Tree from raw data, much like B-tree

Two parameters in clustering B: branching factor of CF Tree T: radius threshold of CF Vector

Parameters control how fine micro-clusters are constructed

Hierarchical agglomerative clustering on leaves of CF Tree

Entire process is efficient: O(N)

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Extracted Feature Space

Leaf nodes in final clustering become the new features

More general than the original naïve feature space

Dimensionality could still be moderately high

Use Support Vector Machine for classification

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Experiments

Synthetic Data Generated at motif-expression level Abnormal paths are injected with

abnormal motif-expressions Classifiers

SVM using naïve feature space SVM using extracted feature spaces of

varying refinement levels

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Experiment

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Experiment (2)

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Summary: Moving Object Anomaly Detection

Higher level semantic analysis of moving objects yields better results

Automated feature extraction Future work

Automatic determination of t parameter Better use of feature space hierarchy Other analysis, such as clustering and

local outlier detection for anomaly detection

Mining other knowledge for moving objects

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Mining Object, Spatial and Multi-Media Data

Mining object data sets

Mining spatial databases and data warehouses

Spatial DBMS

Spatial Data Warehousing

Spatial Data Mining

Spatiotemporal Data Mining

Mining multimedia data

Summary

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Similarity Search in Multimedia Data

Description-based retrieval systems Build indices and perform object retrieval

based on image descriptions, such as keywords, captions, size, and time of creation

Labor-intensive if performed manually Results are typically of poor quality if

automated Content-based retrieval systems

Support retrieval based on the image content, such as color histogram, texture, shape, objects, and wavelet transforms

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Queries in Content-Based Retrieval Systems

Image sample-based queries Find all of the images that are similar to the

given image sample Compare the feature vector (signature) extracted

from the sample with the feature vectors of images that have already been extracted and indexed in the image database

Image feature specification queries Specify or sketch image features like color,

texture, or shape, which are translated into a feature vector

Match the feature vector with the feature vectors of the images in the database

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Approaches Based on Image Signature

Color histogram-based signature The signature includes color histograms based

on color composition of an image regardless of its scale or orientation

No information about shape, location, or texture Two images with similar color composition may

contain very different shapes or textures, and thus could be completely unrelated in semantics

Multifeature composed signature Define different distance functions for color,

shape, location, and texture, and subsequently combine them to derive the overall result

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Wavelet Analysis

Wavelet-based signature

Use the dominant wavelet coefficients of an

image as its signature

Wavelets capture shape, texture, and location

information in a single unified framework

Improved efficiency and reduced the need for

providing multiple search primitives

May fail to identify images containing similar

objects that are in different locations.

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One Signature for the Entire Image?

Walnus: [NRS99] by Natsev, Rastogi, and Shim Similar images may contain similar regions, but a

region in one image could be a translation or scaling of a matching region in the other

Wavelet-based signature with region-based granularity Define regions by clustering signatures of

windows of varying sizes within the image Signature of a region is the centroid of the cluster Similarity is defined in terms of the fraction of the

area of the two images covered by matching pairs of regions from two images

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Multidimensional Analysis of Multimedia Data

Multimedia data cube Design and construction similar to that of

traditional data cubes from relational data Contain additional dimensions and measures for

multimedia information, such as color, texture, and shape

The database does not store images but their descriptors Feature descriptor: a set of vectors for each

visual characteristic Color vector: contains the color histogram MFC (Most Frequent Color) vector: five color centroids MFO (Most Frequent Orientation) vector: five edge

orientation centroids Layout descriptor: contains a color layout vector

and an edge layout vector

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Multi-Dimensional Search in Multimedia Databases

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Color histogram Texture layout

Multi-Dimensional Analysis in Multimedia

Databases

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Refining or combining searches

Search for “blue sky”(top layout grid is blue)

Search for “blue sky andgreen meadows”(top layout grid is blue and bottom is green)

Search for “airplane in blue sky”(top layout grid is blue and keyword = “airplane”)

Mining Multimedia Databases

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REDWHITE

BLUE

GIFJPEG

By Format

By Colour

Sum

Cross Tab

REDWHITE

BLUE

Colour

Sum

Group By

Measurement

JPEGGIF Small

Very Large

REDWHITEBLUE

By Colour

By Format & Colour

By Format & Size

By Colour & Size

By FormatBy Size

Sum

The Data Cube and the Sub-Space Measurements

Medium

Large

• Format of image• Duration• Colors• Textures• Keywords• Size• Width• Height• Internet domain of image• Internet domain of parent pages• Image popularity

Mining Multimedia Databases

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Mining Multimedia Databases in

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Classification in MultiMediaMiner

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Special features: Need # of occurrences besides Boolean existence,

e.g., “Two red square and one blue circle” implies

theme “air-show” Need spatial relationships

Blue on top of white squared object is associated with brown bottom

Need multi-resolution and progressive refinement mining

It is expensive to explore detailed associations among objects at high resolution

It is crucial to ensure the completeness of search at multi-resolution space

Mining Associations in Multimedia Data

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Spatial Relationships from Layout

property P1 next-to property P2property P1 on-top-of property P2

Different Resolution Hierarchy

Mining Multimedia Databases

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From Coarse to Fine Resolution Mining

Mining Multimedia Databases

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Challenge: Curse of Dimensionality

Difficult to implement a data cube efficiently given a large number of dimensions, especially serious in the case of multimedia data cubes

Many of these attributes are set-oriented instead of single-valued

Restricting number of dimensions may lead to the modeling of an image at a rather rough, limited, and imprecise scale

More research is needed to strike a balance between efficiency and power of representation

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Summary

Mining object data needs feature/attribute-based generalization methods

Spatial, spatiotemporal and multimedia data mining is one of important research frontiers in data mining with broad applications

Spatial data warehousing, OLAP and mining facilitates multidimensional spatial analysis and finding spatial associations, classifications and trends

Multimedia data mining needs content-based retrieval and similarity search integrated with mining methods

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References on Spatial Data Mining

H. Miller and J. Han (eds.), Geographic Data Mining and Knowledge Discovery, Taylor and Francis, 2001.

Ester M., Frommelt A., Kriegel H.-P., Sander J.: Spatial Data Mining: Database Primitives, Algorithms and Efficient DBMS Support, Data Mining and Knowledge Discovery, 4: 193-216, 2000.

J. Han, M. Kamber, and A. K. H. Tung, "Spatial Clustering Methods in Data Mining: A Survey", in H. Miller and J. Han (eds.), Geographic Data Mining and Knowledge Discovery, Taylor and Francis, 2000.

Y. Bedard, T. Merrett, and J. Han, "Fundamentals of Geospatial Data Warehousing for Geographic Knowledge Discovery", in H. Miller and J. Han (eds.), Geographic Data Mining and Knowledge Discovery, Taylor and Francis, 2000

K. Koperski and J. Han. Discovery of spatial association rules in geographic information databases. SSD'95.

Shashi Shekhar and Sanjay Chawla, Spatial Databases: A Tour , Prentice Hall, 2003 (ISBN 013-017480-7). Chapter 7.: Introduction to Spatial Data Mining

X. Li, J. Han, and S. Kim, Motion-Alert: Automatic Anomaly Detection in Massive Moving Objects”, IEEE Int. Conf. on Intelligence and Security Informatics (ISI'06).

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