I hope I am posting in the correct forum. A colleague and I gave a problem on a test recently that we're debating over. I hope that someone can help. It is as follows:
Which of the following statements if true about block design?
i. Treatments are assigned haphazardly to experimental units
ii. It controls for the effects of confounding variables
iii. Experimental units are examined before receiving treatments
(a) I only
(b) I and III only
(c) I and II only
(d) II only
(e) III only
I understand I is false and II is true, but we're debating over III. Since it is blocking I believe the experimental units would need to be 'examined' beforehand so that we know how to block them (knowing some characteristic about them seems to qualify as an examination to an extent). He thinks not. Clearly II and III is not an option, but I'm having a hard time picking (d) since it says II ONLY. Am I incorrect in my thinking?
Which of the following statements if true about block design?
i. Treatments are assigned haphazardly to experimental units
ii. It controls for the effects of confounding variables
iii. Experimental units are examined before receiving treatments
(a) I only
(b) I and III only
(c) I and II only
(d) II only
(e) III only
I understand I is false and II is true, but we're debating over III. Since it is blocking I believe the experimental units would need to be 'examined' beforehand so that we know how to block them (knowing some characteristic about them seems to qualify as an examination to an extent). He thinks not. Clearly II and III is not an option, but I'm having a hard time picking (d) since it says II ONLY. Am I incorrect in my thinking?