Practical Stats is offering two courses in Tampa this November, just
prior to the SETAC conference the following week. See our website
for more information, instructor qualifications, and to register.
Pass this along to others who might be interested.
Nondetects And Data Analysis
Correctly handle data below detection limits
Nov 11-12, 2008 $795
Mainsail Suites and Conference Center, Tampa, FL
register at http://www.practicalstats.com/new_classes/classes.html
For most environmental professionals, the way to deal with
"nondetects" is less than obvious. Values below detection or
quantitation limits result from measuring trace amounts of a variety
of organic and inorganic chemicals. Methods such as substitution of
one-half the detection limit are still being used and recommended
even though they produce invasive data that result in incorrect
estimates, regression lines and hypothesis tests. This course
presents up-to-date (maximum likelihood and survival analysis)
methods for computing summary statistics, performing hypothesis
tests, regression modeling and trend analysis for data with one or
more detection limits. Example problems are worked in class, so
students can confidently take these methods back to their office.
Routines in commercial software as well as the free R statistical
system are highlighted. A full course outline is available on the
Practical Stats website. This course assumes a knowledge of basic
statistics, including familiarity with t-tests, linear regression,
and simple nonparametric tests like the rank-sum test.
Untangling Multivariate Relationships
Make sense of complex inter-relationships
Nov 13-14, 2008 $895
Mainsail Suites and Conference Center, Tampa FL
register at http://www.practicalstats.com/new_classes/classes.html
Environmental measurements often are simultaneously recorded as a
series of variables or species. Multiple chemicals are analyzed.
Multiple measures of ecosystem health are recorded. If statistics are
computed on each, one by one, the interrelations among variables,
species and locations cannot be seen. Valuable information is lost.
Multivariate methods resolve what at first may look like noise into
recognizable patterns, providing new insight into the field of study.
However, these methods are daunting to many scientists, with acronyms
like PCA, CCA or CANOCO, and with unfamiliar terms like varimax
rotation and detrended correspondence. The learning curve seems
steep, and useful procedures go unused.
UMR covers the multivariate methods of primary interest to
environmental science, focusing on what each method is designed to
do, when to use them, and when not to. Methods for simplifying and
plotting data (ordination) are contrasted with those for establishing
connections between and among source and response variables.
Capabilities of various software packages are reviewed. Example data
sets are analyzed by each student in class. Our goal is that students
leave with a clear understanding of which method to use, and how to
use it, for their own data.
Regards,
Dennis Helsel
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Dennis R. Helsel, Ph.D. Sign up for our newsletter at:
Practical Stats http://practicalstats.com/news
9278 S. Lark Sparrow Dr.
Littleton, CO 80126-5232 [EMAIL PROTECTED]
