Statistics Meeting Book (May 15, 2019)

Relation to usual C metamer statistics

• Recovery = 10 pBias ~ 1 + 2.303 pBias • RSD(r) = 2.303 pSD(r) • RSD(L) = 2.303 pSD(L) • RSD(R) = 2.303 pSD(R) • 2.303 = ln(10), artifact of using log 10

instead of ln

• Note that ‘Recovery’ and ‘RSDs’ are inappropriate terms in pC metamer. They are approximations to the concepts of pBias, pSD(r), pSD(L) and pSD(R).

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copyright 2018 by Least Cost Formulations, Ltd., all rights reserved.

Sample A data

AOAC International Interlaboratory Study Workbook

Version:

4.1

Blind (Unmatched) Replicates Data Sheet

NIST Cucuminoids

Name of study: Date of study: Sample/Matrix ID: Analyte:

4/1/2018

A

Curcumin

Factor for Units of measurement: Metamer to analyze (C or pC): True value (blank if not known):

1.00E-03 (% = 1E-2, mg/100g = 1E-5, ppm = 1E-6, ppb = 1E-9, etc.)

pC (Enter C or pC)

pC

1.9570

pC log10 offset or zero:

0.0000 (to avoid zero argument)

INSTRUCTIONS:

1. Enter information in YELLOW, boxed cells ONLY! 2. Leave unused cells empty. 3. Do NOT delete or insert Rows or Columns! 4. To remove data, select the range of cells and press the "Delete" key. 5. The worksheet is protected: To paste values from another sheet, use Edit|Paste Special|Value

DATA TO BE ANALYZED (C or pC metamer):

RAW DATA (C metamer):

Replicate Replicate Replicate Replicate Replicate

Actual

Replicate Replicate Replicate

Laboratory

1

2

3

4

5

Lab

1

2

3

1 2 3 4 5 6 7 8 9

1.948 2.013 1.914 1.968 1.990 2.057 1.961 1.936 1.964

1.947 2.013 1.889 1.952 2.000 2.050 1.973 1.917 1.973

1.943 2.012 1.899 1.951 2.008 2.038 1.968 1.959 1.958

O404 O407 O416 O419 O433 O437 O446 O449 O455

11.262 11.297 11.414 9.710 9.710 9.730 12.190 12.920 12.610 10.760 11.170 11.200 10.222 9.990 9.824 8.780 8.920 9.160 10.930 10.650 10.760 11.589 12.095 11.001 10.866 10.634 11.014

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copyright 2018 by Least Cost Formulations, Ltd., all rights reserved.