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Single comment threadYou are looking at one branch of [Lab] 18th independent test on SWB — 99.4% on a claimed 99.0%, and the trend is the interesting part — 58 comments in the full submission. View in context.
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c/hplc·submitted 2 years ago by u/phase_two_pete

[Lab] 18th independent test on SWB — 99.4% on a claimed 99.0%, and the trend is the interesting part

Labbranch of 8 comments

Numbers in the title, numbers in the post. 18th independent test on SWB — 99.4% on a claimed 99.0%, and the trend is the interesting part. Numbers, in the order they matter: 99.4% and 99.0%. Gave the same trace to two people I trust and got two integrations about a point apart. That was the most educational afternoon…

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8 comments, started 2 years ago
u/sig_figs_samMOD1k points·2 years ago

Retitled: the original claimed a comparison the post does not actually make.

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u/santiago_villalobos241 points·2 years ago

A shoulder that does not baseline-resolve cannot be quantified honestly. You can report it as an unresolved shoulder, which is useful information, or you can develop the method until it resolves.

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u/quiet_reader_99153 points·2 years ago·edited

A shoulder that does not baseline-resolve cannot be quantified honestly.

Agreed. And the corollary is that the method line on a certificate is not decoration, it is the number’s provenance.

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u/chain_confirm_cpayments180 points·2 years ago

Is that baseline drawn by the software or by hand?

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u/niels_lindqvist88 points·2 years ago

Is that baseline drawn by the software or by hand?

chain_confirm_c is right — the integration choice is a decision and it should be stated alongside the result.

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u/hamza_weiss558 points·2 years ago

That figure cannot be quoted to two decimals off that baseline. The precision is not in the data.

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u/rania_okonkwo362 points·2 years ago

I would not blame the sample yet. Everything you have described is consistent with the column rather than the vial.

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u/andres_restrepo263 points·2 years ago

That figure cannot be quoted to two decimals off that baseline.

Adding one practical thing — run the blank. It answers this before anyone has to argue about it.

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