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Reliability - Accuracy or Reproducibility??? (1 Viewer)

dwatt

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Hey everyone, I've got a question regarding the term "reliability"

The two terms I've been taught are reliability = reliability of the experimental method
validity = accuracy of the results

So, I was surprised in the 2004 HSC Question 20b) that reliability was portrayed as accuracy of the results, and validity as the validity of experimental method.

However, when I did the 2005 HSC Question 12, the reliability had now become the reliability of the experimental method.

So what is going on? Can anyone let me know why there seems to be a dichotomy here???

Thanks a lot
 

dwatt

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Thanks for that - that's what I thought. I guess the 2004 HSC was a little confused with itself.
 

morganforrest

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My understanding is that validity = accuracy of the results while reliability = reliability of the experimental method AND subsequent reproducability of the results (though I suppose this could be a way to test reliability)

yes or no??
 

conroy1234

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yeah heat losses to the environment do make the molar heat of combustion pretty inaccurate
but if you're comparing it to the molar heat of combustion of other fuels (eg. 1-butanol to 1-propanol) then the heat losses are all the same as each other, so you can still determine their relative heat's of combustion to each other
 

wrxsti

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conroy1234 said:
yeah heat losses to the environment do make the molar heat of combustion pretty inaccurate
but if you're comparing it to the molar heat of combustion of other fuels (eg. 1-butanol to 1-propanol) then the heat losses are all the same as each other, so you can still determine their relative heat's of combustion to each other
you cant assume that..............
 

dwatt

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So the idea is it's a reliable procedure (assuming you can get reproducibility), yet the value will be invalid, due to heat loss/incomplete combustion etc.

This is giving me headache!
 

morganforrest

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dwatt said:
So the idea is it's a reliable procedure (assuming you can get reproducibility), yet the value will be invalid, due to heat loss/incomplete combustion etc.

This is giving me headache!
The system is accurate, but not precise

Accuracy and Precision are the two terms I learned.

Accuracy = fire lots of arrows at the target and hit the target every time
Precise = fire one arrow at the target and get a bullseye
 

nadz001

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dwatt said:
Hey everyone, I've got a question regarding the term "reliability"

The two terms I've been taught are reliability = reliability of the experimental method
validity = accuracy of the results

So, I was surprised in the 2004 HSC Question 20b) that reliability was portrayed as accuracy of the results, and validity as the validity of experimental method.

However, when I did the 2005 HSC Question 12, the reliability had now become the reliability of the experimental method.

So what is going on? Can anyone let me know why there seems to be a dichotomy here???

Thanks a lot
validility is seen as to get the correct answer so look at the intruments, are they able to give u a coorect answer eg in an answer u woud use AAS TO find Sulphateconcentration due to its not a metak ion and aas is used more metal ions, reliablity is to see if results are consistant so if ur experimental method is incorrect then ur results r not going to be consistan therefore it wont be reliable
 

nadz001

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[
validility is seen as to get the correct answer so look at the intruments, are they able to give u a coorect answer eg in an answer u woud use AAS TO find Sulphateconcentration due to its not a metak ion and aas is used more metal ions, reliablity is to see if results are consistant so if ur experimental method is incorrect then ur results r not going to be consistan therefore it wont be reliable
 

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