Question

Which of the following designs best eliminates differences between experimental and control groups?

1) Johnny conducted a within-participants experiment where he intentionally assigned male participants to the control condition and females to his experimental condition in attempts to rule out differences within each group.
2) Kevin conducted a between-participants experiment, where he randomly assigned participants to a condition. They then completed both the control and experimental manipulations.
3) Heather conducted a between-participants experiment where she intentionally assigned male participants to the control condition and females to his experimental condition in attempts to rule out differences within each group.
4) Laura conducted a within-participants experiment, where each participant completed the control and experimental condition.

Answer 1

Laura's within-participants experiment where each participant completed both the control and experimental condition is the design that best eliminates differences between experimental and control groups.

Step-by-step explanation:

The design that best eliminates differences between experimental and control groups is:

4) Laura conducted a within-participants experiment, where each participant completed the control and experimental conditions.

Within-participants experiments, also known as repeated measures designs, involve the same participants being exposed to both the control and experimental conditions. This design helps eliminate individual differences between participants because each participant serves as their control. It allows for direct comparisons within the same individuals, minimizing the impact of individual differences that could potentially affect the outcomes. This design is particularly effective in controlling for individual variability, enhancing the ability to detect the actual effects of the experimental manipulation.