Which of the following is an example of random error in ...

[Evvie72]

Which of the following is an example of random error in measurement?
 
  a. Consistent use of a tuning fork pitched too high
  b. Inadvertent deletion of one question from the questionnaire sent to all subjects in a study
  c. Occasional discussion of questions with some subjects during completion of the measurement tool
  d. Use of a mismarked tape measure to determine infant head circumference

Question 2

The difference between the observed score and what exists in reality (true score) is called:
 
  a. homogeneity.
  b. measurement error.
  c. split-half reliability.
  d. standard deviation.

[bfulkerson77]

Answer to Question 1

ANS: C
Random error can occur with variations in the administration of the measurement procedure, if subjects accidentally mark the wrong answer, or data are entered incorrectly into the computer in preparation for data analysis.
Although the measurements would be off, they would all be in the same direction.
Since all subjects received that same questionnaire, this would not represent random error.
Even though mismarked, the tape measure was used for all measurements and would not be random error.

Answer to Question 2

ANS: B
Measurement error is the difference between the true score and what in reality is measured (observed score).
Homogeneity is a sameness of data with regard to a certain variable.
Split-half reliability is a process that determines the likeness of items within an instrument.
The standard deviation measures how much scores differ from the mean.

[Evvie72]

TYSM

[Jossy]

Excellent