Jellyfish Compliance with SQIDEP · MCU15/0122

                                                                                                                                                         7
                                                                                                                      Technical Papers


 Table 10. Number of paired samples            THE AUTHORS                                          McDonald J (2014): Paired t-test, Log Normal
 required to establish CRE% at the                                                                    Transformations and Wilcoxon Ranked Sign Test,
                                                             Charles Kelly (email: charles.
 90% Confidence level and 80%                                                                         Handbook of Biological Statistics, 3rd ed., Sparky
 Power level.                                                [email protected]) has over               House Publishing, Baltimore, Maryland.
                                                             16 years’ experience in the
                       TSS      TP      TN                   construction, consulting and           Neyman J (1937): Outline of a Theory of Statistical
                                                                                                      Estimation Based on the Classical Theory of
 Z-Score (Zα/2)        1.64    1.64     1.64                 manufacturing industries.
                                                                                                      Probability, University College, London.
                                                             He is currently Commercial
 Z-Score (Zβ)          0.84    0.84     0.84
                                               Manager – Humes Water Solutions and is               Olsson U (2005): Confidence Intervals for the Mean
 COV                   0.07    0.44     0.54   undertaking research and development of                of a Log-Normal Distribution, Swedish University
                                               existing and new stormwater treatment                  of Agricultural Sciences, Journal of Statistics
 % Removal             91%     63%      51%                                                           Education, 13, No 1.
                                               products for the Australian market.
 Number of paired                              Charles holds a Bachelor’s degree in                 Park H (2008): Hypothesis Testing and Statistical
 samples required                              Environmental Engineering, and a PhD in
                       0.05    5.57     15.9                                                          Power of a Test, The University Information
 to meet 90%
 Confidence Interval
                                               Mechanical/Environmental Engineering.                  Technology Services (UITS) Center for Statistical
                                                                                                      and Mathematical Computing, Indiana
                                                             Anton Bardak is a Civil                  University, US.
engagement and consultation is required
                                                             Engineer with three years’
to determine the most appropriate                                                                   Privitera G (2011): Chapter 8: Introduction to
                                                             experience in the water
approach for calculating the minimum                                                                   Hypothesis Testing, Statistics for the Behavioral
                                                             engineering industry.
number of required paired samples.                                                                     Sciences, 225, Sage Publications.
                                                             After two years with KBR
CONCLUSION                                                   as a graduate water and                Razali M & Wah Y (2011): Power Comparisons of
                                               wastewater engineer, he joined Humes                   Shapiro-Wilk, Kolmogorov-Smirnov, Lilliefors and
The draft Stormwater Australia
                                               as a Water Solutions Engineer and now                  Anderson-Darling Tests, Journal of Statistical
Stormwater Quality Improvement Device                                                                 Modelling and Analytics, 2, pp 21–33.
Evaluation Protocol (SQIDEP) requires          focuses solely in the area of stormwater
inter alia, statistical assessment of the      management. Anton provides technical                 Seo S (2002): A Review and Comparison of

data presented. It is necessary to engage      support and designs for the national                   Methods for Detecting Outliers in Univariate

with academia and regulators to reach          Humes business and is also heavily involved            Data Sets, Graduate School of Public Health,
                                               in ongoing research and development.                   Pittsburgh University, US.
a consensus on the robustness of a
statistical approach, and this paper is                                                             Shapiro S & Wilk M (1965): An Analysis of
                                               REFERENCES
offered as an exemplar approach to                                                                    Variance Test for Normality (Complete
                                               Bonacci K (2012): Central Limit Theorem, Indiana
help inform the discussion.                                                                           Samples), Biometrika, 52, p 591, Great Britain.
                                                 University Southeast, viewed at homepages.
                                                 ius.edu/kbonacci/HOMEPAGE%20K300_files/            Shier R (2004): Statistics: Paired t-tests,
  The following statistical procedures           K300%206-5.pdf                                        Mathematics Learning Support Centre, www.
have been proposed:
                                               Burton A & Pitt R (2002): Stormwater Effects            statstutor.ac.uk/resources/uploaded/paired-t-
1. Outlier Identification in raw data            Handbook: A Toolbox for Watershed Managers,           test.pdf
  and removal if justified                       Scientists, and Engineers, Lewis Publishers.
                                                                                                    Singh A, Singh A & Engelhardt M (1997): The
                                               Cramér H (1946): Mathematical Methods of                Lognormal Distribution in Environmental
2. Normal distribution validation of raw
                                                 Statistics, Princeton University Press, Asia          Applications, United States Environmental
  data (data transformation conducted            Publishing House.
                                                                                                       Protection Agency, EPA/600/S-97/006.
  if required)
                                               Duncan H (1999): Urban Stormwater Quality:
                                                                                                    Stormwater Australia (2014): Evaluation
3. Statistical significance of influent and      A Statistical Overview (Report 99/3), Monash
                                                 University, Melbourne, Australia.                     Protocol (SQIDEP) for Stormwater Quality
  effluent data (paired t-test, or a non-                                                              Treatment Devices, Consultation Release by
  parametric alternative if not normally       Geosyntec Consultants & Wright Water Engineers
                                                                                                       Stormwater Australia viewed at stormwater.
  distributed)                                   (2009): Urban Stormwater BMP Performance
                                                                                                       asn.au/images/SQID/SQIDEP_Release_version_
                                                 Monitoring, Water Environment Research
                                                 Foundation, viewed at www.bmpdatabase.                December_2014.pdf
4. Confidence Interval calculation
  of removal efficiency metric                   org/Docs/2009%20Stormwater%20BMP%20                Tan S & Tan S (2010): The Correct Interpretation of
                                                 Monitoring%20Manual%20(Interim%20Ch%20               Confidence Intervals, Proceedings of Singapore
5. Minimum number of paired samples              1-6,%20App).pdf
                                                                                                      Healthcare, 19, 3.
  calculated.                                  Geyer C (2003): Nonparametric Tests and
                                                                                                    Teixeira A, Rosa A & Calapez T (2009): Statistical
                                                 Confidence Intervals, School of Statistics,
   Some discussion is still required             University of Minnesota.                              Power Analysis with Microsoft Excel: Normal
around point 5, but if all the steps                                                                   Tests for One or Two Means as a Prelude to
                                               Herr C & Sansalone J (2015): In Situ Volumetric
above are completed and the statistical                                                                Using Non-Central Distributions to Calculate
                                                 Filtration Physical Model to Separate
tests are satisfied, then consultants and                                                              Power, Journal of Statistics Education, 17, 1.
                                                 Particulate Matter from Stormwater. Journal
authorities will have a sound scientific         of Environmental Engineering, 10.1061/(ASCE)       Tukey J (1977): Exploratory Data Analysis, Addison-
basis for accepting treatment efficacy           EE.1943-7870.0000946, 04015017.                      Wesley.
claims of the device.                          Kelly C & Bardak A (2015): Evaluation of Treatment   Walfish S (2006): A Review of Statistical Outlier
                                                 Performance of a Stormwater Treatment
  Just as importantly, this process                                                                   Methods. Pharmaceutical Technology, viewed
                                                 Membrane Filter under Australian Conditions,
will establish objective performance                                                                  at www.pharmtech.com/review-statistical-outlier-
                                                 Australian Journal of Water Research, 2, 2,
evaluations, reduce contestable decisions;       pp 2203–9490.                                        methods.
result in benefits for the community and       Limpert E, Stahel W & Abbt M (2001): Log-Normal      Wang F (2001): Confidence Interval for the Mean
authorities; and allow for a clear path to        Distributions Across the Sciences: Keys and         of Non-Normal Data, Quality and Reliability
market for device proprietors.                    Clues, BioScience, 51, 5.                           Engineering International, 17, pp 257–267.




                                                                                                                                MAY 2015 WATER