Given an experiment with the following syntax: R O1 X O2 R O3 ...

[BrownTown3]

Given an experiment with the following syntax:
  R O1 X O2
  R O3 O4
  R X O5
  R O6
 
  Discuss what kind of design this syntax represents; whether it is pre-experimental, quasi-experimental, or true experimental; and which extraneous variables it controls for. Explain how treatment effects can be separated from other effects.

Question 2

An estimate of the population mean in the form of a single value, usually the sample mean, is called a _____.
 a. confidence interval estimate
  b. standard deviation
  c. point estimate
  d. variant

[mtmmmmmk]

Answer to Question 1

This design is called a Solomon four-group design. It is a true experimental design that controls for all extraneous variables. Where TE is the treatment effects, EXT is the extraneous effects, and IT is the interactive testing effect,
O2  O1 = TE + EXT + IT
O4  O3 = EXT
O5  O1 = TE + EXT
O5  O3 = TE + EXT
O6  O1 = EXT
O6  O3 = EXT
This allows solving for treatment effects separately from extraneous effects and the interactive testing effect. Simply,
TE = O5  O6
IT = O2  O5
EXT = O6  O1 or O6  O3 or O4  O3
However, to maximize statistical power and minimize the potential for bias, the results of the four groups are generally used equally.

Answer to Question 2

C

[BrownTown3]

Excellent

[Bigfoot1984]

Great answer, keep it coming