Maintaining a calculator means checking the arithmetic against hand-worked cases at each review, not checking that it still loads.
Topic summary
Validating a calculator against hand arithmetic — what changed since
This is a generated summary. It shows the 9 most-liked posts from a topic of 138, in their original order, with the accepted answer included where one exists. It is a reading aid and it will miss nuance — the full topic is the record.
n.osei, post #13: Why calculators are not medical advice: they do arithmetic. Medical decisions are not arithmetic. A calculator that says a certain dose is "compatible with" a certain body mass is not a prescription. Adding the caveat now so it does not have to be extracted later. Go to post
I disagree with the framing of Validating a calculator against hand above, and I think it is a substantive disagreement rather than a terminological one. Setting out why, so it can be checked.
The reasoning depends on an assumption that is doing a lot of work and is never stated. If the assumption holds, the conclusion follows. I do not think it holds generally.
k.batista, post #40: Post #39 is right about the mechanism and I think understates the practical bit. Precision and significant figures: the calculators do not round to match your input precision. If you input values to one decimal place, the output might have more. Use significant figures appropriate to your input precision. Go to post
The most useful reply I ever got about Validating a calculator against hand was a request to state my units. It sounds like pedantry and it has saved me twice.
t.tulloch, post #55: The number people quote for Validating a calculator against hand is a central estimate presented without its interval, and the interval is wide enough that the estimate is nearly uninformative on its own. Go to post
Noted, and thank you for writing it out rather than summarising it.
Second this, and I would have said it less carefully.
30 likes 14mo
Confirming post #130 from a second method, which matters more than confirming it from a second person.
A calculator that shows its working is worth ten that give an answer. The whole value is being able to see which step you disagree with.
It reads as pedantry until the day it does not.
29 likes 13mo
Read the full topic (138 posts)
This topic was referenced in
- Second pass at: The mass-error checker and its intended scopeData & Tools › Calculators · 74 replies
- Second pass at: The storage lookup and where its data comes fromData & Tools › Calculators · 42 replies
Suggested topics
| Topic | Participants | Replies | Views | Activity |
|---|---|---|---|---|
|
A calculator that gives a right answer to the wrong question — does this still hold?
A calculator that gives a right answer to the wrong question — does this still hold? I have a specific reason for asking rather than idle curiosity, and the context is below. Posting the calculation with the…
|
+23 | 27 | 62k | 8mo |
|
Coming back to: Feature request: should a dose-equivalence tool exist at all?
Feature request: should a dose-equivalence tool exist at all? I have a specific reason for asking rather than idle curiosity, and the context is below. Reading back through what has been written here about…
|
+37 | 41 | 725 | 7mo |
|
Revisiting: Bug report: the reconstitution calculator and a rounding edge case
Revisiting: Bug report: the reconstitution calculator and a rounding edge case — setting out what I have, and where I think it stops being reliable. Posting the calculation with the inputs, so that somebody…
|
+109 | 122 | 5.8k | 17mo |
|
Follow-up: Bug report: the reconstitution calculator and a rounding edge case
On the subject in the title: Bug report: the reconstitution calculator and a rounding edge case Working notes rather than a conclusion. Posting the calculation with the inputs, so that somebody can disagree…
|
+58 | 63 | 24k | 5mo |
|
Validating a calculator against hand arithmetic
Validating a calculator against hand arithmetic Writing it up because I had to work it out twice and would rather nobody else did. Validating a calculator against hand: setting out the arithmetic in full,…
|
+17 | 21 | 12k | 3mo |
Related topics — sharing the tags concentration maths, site feedback, worked example
| Topic | Participants | Replies | Views | Activity |
|---|---|---|---|---|
|
Coming back to: Why I now write the concentration on the vial in marker
The question in the title: Why I now write the concentration on the vial in marker I will give what I have already checked below so nobody repeats it. Writing this out with the numbers in it, because…
|
+8 | 12 | 4.3k | 1d |
|
An ABAB design with a data table and honest limitations — a second dataset
On the subject in the title: An ABAB design with a data table and honest limitations — a second dataset Working notes rather than a conclusion. Posting a small dataset on ABAB design. It is mine, it is…
|
+106 | 118 | 25k | 4mo |
|
A 10 mg vial reconstituted three different ways, compared
Posting this under the heading it deserves: A 10 mg vial reconstituted three different ways, compared Everything below is what sits behind that. Something about 10 mg vial reconstituted three does not…
|
+30 | 34 | 55k | 17h |
|
A 10 mg vial reconstituted three different ways, compared — the long version
A 10 mg vial reconstituted three different ways, compared — the long version — setting out what I have, and where I think it stops being reliable. Asking about 10 mg vial reconstituted three directly, because…
|
+146 | 158 | 47k | 9mo |
|
Follow-up: Request: a per-category review queue
On the subject in the title: Request: a per-category review queue Working notes rather than a conclusion. A follow-up question about per-category review queue that I did not know to ask the first time. The…
|
2 | 14k | 4mo |