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A STATISTICIAN COLLABORATING WITH ECOLOGISTS: from EXAMPLES to LESSONS LEARNED. N. Scott Urquhart Senior Research Scientist Department of Statistics Colorado State University (June, 2004). This research is funded by U.S.EPA – Science To Achieve Results (STAR) Program Cooperative
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A STATISTICIAN COLLABORATING WITH ECOLOGISTS:from EXAMPLES to LESSONS LEARNED N. Scott Urquhart Senior Research Scientist Department of Statistics Colorado State University (June, 2004)
This research is funded by U.S.EPA – Science To Achieve Results (STAR) Program Cooperative Agreement # CR - 829095 FUNDING ACKNOWLEDGEMENT This talk was developed under the STAR Research Assistance Agreement CR-829095 awarded by the U.S. Environmental Protection Agency (EPA) to Colorado State University. This presentation has not been formally reviewed by EPA. The views expressed here are solely those of presenter and STARMAP, the Program he represents. EPA does not endorse any products or commercial services mentioned in this presentation.
PATH FOR TODAY • Autobiographical Sketch • Some lessons learned • Listed first, then • Illustrated from experience • Questions are welcome at any time
BIOGRAPHY of NSU • Grew up in agriculture in Western Colorado • Very familiar with the business end of dairy cows • Manual labor of 1950’s vintage agriculture • Motivation for higher education = HIGH • Came to CSU in 1958 • Started in math, but considered civil engineering through first year
BIOGRAPHY - continued • Statistical calculation of 1950’s was done on rotary calculators • IBM electronic accounting equipment • Two computers in Colorado then! • Went to work in the CSU “Computing Center” Spring, 1959 • Predecessor of both Computing Center and • Stat Lab • Took the graduate statistical methods course the summer after my freshman year • Been at stat ever since
LESSON LEARNED • Your professional world will change in major ways during your career! • Implication: Plan for it by learning how to think and learn. You will have to engage in learning throughout your career.
STATISTICAL COMPUTATION HAS CHANGED! STATISTICAL COMPUTATION HAS CHANGED! --- SO WHAT? • The more powerful of the two computers in Colorado at that point was an IBM 704 • About 1985 I realized that the IBM XT on my desk • 10M (not gig) hard disk • 8088 + 8087 = processors • More power than the 704 0f 25 years earlier! • Implication = ? • Be prepared for CHANGE • Learn how to learn about all of ecology, statistics, and mathematics
LESSONS LEARNED • Your professional world will change in major ways during your career! • Implication: Plan for it by learning how to think and learn. You will have to engage in learning throughout your career. • Most easy problems have been solved. • Relevant problems will require teamwork. • Corollary: Ecologists, Statisticians and Mathematicians need to understand each others’ perspectives • Ecologists – take collaborating statisticians and mathematicians to the field with you. Statisticians and mathematicians – GO! Invite yourself, if necessary. • Statistics can make a difference • Mathematics can, too, but my examples deal with statistics
ILLUSTRATIONS • Collaboration with plant ecophysiologists in Arctic Alaska • = “North Slope” • Collaboration with the Grand Canyon Monitoring and Research Center (GCMRC), Flagstaff, AZ • Monitoring of the terrestrial plant ecology near the Colorado River in the Grand Canyon • EPA’s Environmental Monitoring and Assessment Program (EMAP) • My major collaboration for the past 14 years
ILLUSTRATIONS • Collaboration with plant ecophysiologists in Arctic Alaska • = “North Slope”
R4D PROJECT ON ALASKA’S“NORTH SLOPE” • FUNDED BY DEPARTMENT OF ENERGY • INCLUDED A STUDY ECOLOGICAL PROCESSES • OF PLANTS • WITH THE VIEW OF PREDICTING LIKELY RESPONSE TO DISTURBANCES, • LIKE THE DEVELOPMENT OF AN OIL FIELD • MAJOR STUDY SITE = IMNAVIAT CREEK
GENERAL GOALS OF R4D • DEVELOP ECOPHYSIOLOGY MODELS FOR PLANTS ON THE NORTH SLOPE • TO SUPPORT MORE GENERAL MODELS TO ALLOW EVALUATION OF LIKELY IMPACT OF ENERGY- RELATED DEVELOPMENT • NSU: ON-SITE EXPERIMENTAL AND SAMPLING DESIGN • FOR MANY STUDIES
R4D PROJECT ON ALASKA’S “NORTH SLOPE”- continued • A SMALL QUESTION IN THE LARGER QUESTION: • “WHAT MAKES STONE STRIPES” • WATER SEEMS AVAILABLE IN VEGETATION BETWEEN STONE STRIPES • ELEVATION DOESN’T SEEM TO EXPLAIN • STUDY: COMPARE PHYSIOLOGICAL PROCESSES OF PLANTS IN STONE STRIPE TO THOSE OF PLANTS IN IMMEDIATELY ADJACENT PLANTS IN HEAVILY VEGETATED AREA • ?? HOW TO SELECT STUDY PLOTS ??
STONE STRIPES AND EQUIPMENT FOR MEASURING PHOTOSYNTHESIS RATE
R4D PROJECT ON ALASKA’S “NORTH SLOPE”- continued - 2 • PREVIOUS YEAR STAKES HAD BEEN SET ON 100m CENTERS (Orange stakes in an earlier image.) • NSU HAD ARRANGED FOR THREE 100m TAPE MEASURES TO BE AVAILABLE • AND TOOK ALONG A LONG LIST OF PAIRS OF RANDOM DIGITS (00 - 99) • DEFINE THE POPULATION - AWAY FROM THE SITE • “WHAT DO YOU WANT TO SAY IN THE INTRODUCTORY PARAGRAPH OF THE PAPER YOU PLAN TO WRITE ABOUT THIS?” • ===> CRITERIA FOR WHETHER A SPECIFIC m2 PLOT WAS OR WAS NOT IN THE POPULATION
FIELD RESULT OF RANDOMLY SELECTED PLOTS “I WOULD NEVER HAVE PICKED THAT PLOT!!!! BUT I SHOULD HAVE!!!”
THE ENTIRE CONTEXT OF INTEREST HOMOGENEOUS CONTEXT SAMPLED
THE ENTIRE CONTEXT OF INTEREST HOMOGENEOUS CONTEXT SAMPLED
THE ENTIRE CONTEXT OF INTEREST HOMOGENEOUS CONTEXT SAMPLED
LESSON LEARNED - I • OPINION: FOR MOST ECOLOGISTS, A “TYPICAL SITE” IS VARIABLE FOR THE FEATURE OF INTEREST, BUT AS HOMOGENEOUS AS POSSIBLE IN ALL OTHER WAYS • ===> MANY “ECOLOGICAL FACTS” ARE BASED ON VERY BIASED SUBPARTS OF THE SITUATION OF INTEREST
ILLUSTRATIONS • Collaboration with plant ecophysiologists in Arctic Alaska • = “North Slope” • Collaboration with the Grand Canyon Monitoring and Research Center (GCMRC), Flagstaff, AZ • Monitoring of the terrestrial plant ecology near the Colorado River in the Grand Canyon
PROGRAM EVALUATION FOR THE GRAND CANYON MONITORING AND RESEARCH CENTER (GCMRC) • OBJECTIVE • REVIEW THE TERRESTRIAL RESEARCH PROGRAM • EXTERNAL PANEL • BIOLOGISTS & QUANTITATIVE SCIENTISTS • ACADEMIC & FEDERAL EMPLOYEES • FROM GLEN CANYON DAM THROUGH GRAND CANYON TO LAKE MEADE • EVALUATION PANEL OF 8 • 11-DAY RAFT TRIP THROUGH GRAND CANYON • ACCOMPANIED BY 9 PEOPLE WHO HAD CONDUCTED RESEARCH ALONG THE RIVER
DESIGNING AND IMPLEMENTING A VEGETATION STUDY FOR GCMRC • OBJECTIVE - LOCATE AND LAY OUT VEGETATION TRANSECTS • NSU SELECTED 100 POTENTIAL SITES • RANDOMLY, SUBJECT TO SPATIAL RESTRICTIONS • EACH POTENTIAL SITE WAS • DETERMINED TO BE VERTICAL FACED, EFFECTIVELY UNVEGETATED, = NO TRANSECT • OR TRANSECT WAS LAID OUT AND DOCUMENTED • RESULT: • 20 SITES TO BE REVISITED ANNUALLY • 40 SITES TO BE VISITED ONLY ONCE IN THREE YEARS