11/5/2006A Bayesian Network Model...1 A Bayesian Network Model of Stromatolite Formation [Figure adapted from A. C. Allwood et al. Stromatolite reef from.

Slides:



Advertisements
Similar presentations
Writing Suggestions: SAT Essays
Advertisements

Why was stratospheric ozone disappearing above the South Pole?
Relative Dating : Which Came First?
Science Coursework - ISAs
EE 7730 Image Segmentation.
© 2005 The McGraw-Hill Companies, Inc., All Rights Reserved. Chapter 1 Explaining Behavior.
New Hampshire Enhanced Assessment Initiative: Technical Documentation for Alternate Assessments Alignment Inclusive Assessment Seminar Brian Gong Claudia.
1 / x Complex Adaptive systems GRS Introduction Arnold Bregt.
BNFO 602/691 Biological Sequence Analysis Mark Reimers, VIPBG
Automatic Complexity Analysis of Simple Imperative Programs Zachi Mann.
Themes and Elements of Geography
The History of the Earth Dayne Lee Fred Ikeler. Origin of the Universe The universe began about 14.4 billion years ago The Big Bang Theory states that,
Lecture # 6 SCIENCE 1 ASSOCIATE DEGREE IN EDUCATION TEACHING OF SCIENCE AT ELEMENTARY LEVEL.
Genetic Regulatory Network Inference Russell Schwartz Department of Biological Sciences Carnegie Mellon University.
Introduction to Biology
Geology of Australia and New Zealand, HWS/UC Plate Tectonics.
@earthscience92. What is Science? Science – The systematic study of natural events and condition. Anything in living or nonliving world Scientific knowledge.
Introduction to Earth Science
Unit 1 BEDROCK GEOLOGY. The geologic history of the Earth is determined by Earth Science principles such as _________________________ _________________________.
Chapter 1 “The Science of Biology” The goal of science is to investigate and understand, to explain events in nature, and to use those explanations to.
What Is Science? Think Like a Scientist Scientists use many different skills to learn more about the world. Observing Inferring PredictingClassifying Making.
Introduction Osborn. Daubert is a benchmark!!!: Daubert (1993)- Judges are the “gatekeepers” of scientific evidence. Must determine if the science is.
Mr. Boucher. 1 – What is science A – a methodology of thinking B – a way of researching the physical world C – a body of knowledge 2 – Only with all three.
Chapter 1 Sections 1 and 2. 1.What is science? Science is a way of understanding the natural world. 2. What skills do scientists use to understand the.
Define the following terms at the top of your notes for Ch 21!
11/8/2015 Nature of Science. 11/8/2015 Nature of Science 1. What is science? 2. What is an observation? 3. What is a fact? 4. Define theory. 5. Define.
Ch. 23.6: Interpreting the Rock Record
Grade 9 Science SUSTAINABLE ECOSYSTEMS & HUMAN INTERACTIONS
Unit 7 Lesson 2 Relative Dating
Exploring Physical Science Lesson 1 Mrs. Martin. 3 Main Categories of Science Life Science Earth Science Physical Science.
Science Terms TAKS Objective 1.
Intro to Biology Purpose: to introduce the recurring themes of this course and describe the mechanisms by which science is explored.
Key Concepts and Themes of Geography Chapter 1 section 1.
Earth Science Review 6 th Grade. Scientific Inquiry/Methods Scientific inquiry refers to the many ways in which scientist study the natural world and.
Introduction to Life Science. Science is a way of learning about the natural world Scientific inquiry – all the diverse ways in which scientist study.
Scientific Inquiry & Design Scientific Method
ART CRITICISM AND FORMAL ANALYSIS OUTLINE. Defining Art Criticism.
Science is a method for studying the natural world. It is a process that uses observation and investigation to gain knowledge about events in nature. What.
Experimental Psychology PSY 433 Chapter 5 Research Reports.
Geological Time Dating Absolute and Relative. Geologic Time B y examining layers of sedimentary rock, geologists developed a time scale for dividing up.
Rock Relationships and Geological Histories You must have the presentation on Slide Show mode. On opening the presentation, you may be asked to enable.
Fahrenheit 451 / Ralph Steadman In groups, you will analyze a Ralph Steadman Fahrenheit 451 Interpretation These images are from Steadman’s collection:
GEOLOGY Explore how our Earth’s surface is constantly changing. OLD RAG, VA.
Research Methods Systematic procedures for planning research, gathering and interpreting data, and reporting research findings.
Geologic Time. The Geologic Time Scale  A summary of major events in Earth’s past that are preserved in the rock record  Divisions of Geologic Time.
Warm Up 10/8 1) 1) What type of sedimentary rock is formed from weathered particles of rocks and minerals? a. intrusive sedimentary rock b. chemical sedimentary.
Rocks, Fossils, Fossil Fuels
Bell Ringer: 1) Please take out your Flapjack lab
Interpreting Geologic History
Scientific Method.
Experimental Psychology
Visualizing Earth Science
Complete the “Who Dun It” activity at your seat. Be prepared to
Understanding Erosion, Deposition, and Burial
History of Life on Earth
Week 3 Vocabulary Science Scientific Method Engineering Method
DO NOW Pick up notes and Review #11. Turn IN Review #10.
The History of Earth Relative Dating Absolute Dating
The Theory* of Evolution
Qualitative Observation
Metamorphic Rocks Chapter 3, Section 3.4. Science Starter – Write down 5 things you learned in the first 3 weeks of class!
Scientific Method Notes
Geomorphology of Eastern Meridiani Planum
Paleoclimate Proxies A proxy is a natural data set that mimics an environmental change, e.g. increased tree ring width and increased temperature and moisture.
Chapter 1 The Science of Biology.
Bell Work  You will not need to write anything down. We will set up our notebooks Friday. Discuss with your shoulder partner any classroom rules that.
What are systematic reviews and why do we need them?
Scientific Inquiry.
Cylindrical & Spherical Coordinates
Identify the fib (statement that is not true)
Presentation transcript:

11/5/2006A Bayesian Network Model...1 A Bayesian Network Model of Stromatolite Formation [Figure adapted from A. C. Allwood et al. Stromatolite reef from the Early Archaean era of Australia. Nature 441 (8 June 2006), ] Jack K. Horner Science Applications International Corporation

11/5/2006A Bayesian Network Model...2 Problem statement Stromatolites are attached, lithified sedimentary growth structures, accretionary away from a point or limited surface of initiation. Whether stromatolites have a biotic origin is vigorously debated If biotic in origin, the oldest (~3.5 billion years before present) were created by some of the first forms of terrestrial life Because no single piece of evidence at present could decide whether stromatolites are of biotic origin, the debate depends significantly on how to interpret the “evidence as a whole” How do we rigorously represent the notion of the “evidence as a whole”?

11/5/2006A Bayesian Network Model...3 Some requirements (Abstracted from Allwood et al., op. cit.) Cone surfaces have a consistent/inconsistent vertical depth There are systematic differences/similarities between the texture of the cone surfaces and the texture of the laminae between the cones The cones are heterogeneously/homogeneously spaced The cones are absent_from/present_in deep water The cone surfaces exhibit/don’t_exhibit 250-fold enhanced rare earth element (REE) composition The structure of the cone surfaces is consistent/inconsistent with the mat structure of several biotic sources At many sites, individual instances of a given type of cone share/don’t_share common depositional characteristics, over an extended geographic region

11/5/2006A Bayesian Network Model...4 Implementation (Bayesian network) [Origin is the only hypothesis variable, all others are evidence variables. P(Origin = Biotic | X = “upper value”) = 0.9, where X ≠ Types_syndepositional is an evidence variable; else P(Origin = Biotic | X) ~ 0.1N, where N is number of types syndepositional. Argument from Allwood et al., op. cit., is shown.]

11/5/2006A Bayesian Network Model...5 Some results (sensitivity of Origin to evidence variables) Evidence VariableMutual Information Quadratic Score Absent from deep water Similar to biotic mats Cone surface Enhanced REE Constant cone depth Non-uniform cone spacing Types syndepositional

11/5/2006A Bayesian Network Model...6 Discussion Many inference topologies are possible –at present, the literature does not motivate anything more complicated than the model shown above –the Bayesian network method can naturally accommodate more complexity if needed Requirements do not uniquely determine the conditional probabilities –this is a common feature of scientific explanations –the Bayesian network method allows us to rigorously compare effects of probability assignments (e.g., results are almost identical if P(Origin = Biotic | X = “upper value on Slide 4”) = 0.7 (instead of 0.9)