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Author Question: Briefly explain the confounds of instrumentation and mortality. What will be an ideal ... (Read 57 times)

tsand2

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Briefly explain the confounds of instrumentation and mortality.
 
  What will be an ideal response?

Question 2

Under what circumstances is a stratified random sample the most appropriate sampling method?
 
  What will be an ideal response?



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Athena23

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Answer to Question 1

Instrumentation is a threat to internal validity in which changes in the dependent variable may be due to changes in the measuring device. Mortality, or attrition, is a threat to internal validity in which differential dropout rates may be observed in the experimental and control groups, leading to inequality between the groups.

Answer to Question 2

A stratified random sample is appropriate when researchers want to describe and compare different subgroups that make up a population. This type of sampling ensures that each subgroup will be represented with a guaranteed number of participants. Note, a stratified random sample is a probability sample, so the entire population must be known.




tsand2

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Reply 2 on: Jun 19, 2018
Great answer, keep it coming :)


irishcancer18

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Reply 3 on: Yesterday
Wow, this really help

 

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