When conducting an experiment on time management, Jamie assigns everyone who arrives before noon to the experimental group and everyone who arrives after noon to the control group. In the context of experimental research methods, what is wrong with Jamie’s experiment?
The Correct Answer and Explanation is:
The issue with Jamie’s experiment lies in the way participants are assigned to the experimental and control groups. This is an example of selection bias, specifically non-random assignment. In an ideal experimental setup, participants should be randomly assigned to groups in order to control for variables that could influence the outcome, except for the treatment itself.
Here, Jamie’s method of assigning people based on their arrival time is problematic for several reasons:
- Pre-existing Differences: People who arrive before noon might have different characteristics (e.g., motivation, time management skills, or lifestyle) compared to those who arrive after noon. These pre-existing differences could affect their time management abilities and the results of the experiment. By not randomly assigning participants, Jamie cannot ensure that the groups are comparable.
- Confounding Variables: The time of arrival could be correlated with other factors that influence time management, such as work schedules, family commitments, or personal habits. For example, individuals who arrive early may be more conscientious, while those arriving later might face different external pressures or have different daily routines. These confounding factors could skew the experiment’s results, making it unclear whether the observed effects are due to the time of arrival or other variables.
- Lack of Control: Random assignment ensures that each participant has an equal chance of being placed in either the experimental or control group, helping to eliminate biases. By assigning participants based on arrival time, Jamie loses the ability to control for the factors that might influence the results, making it difficult to draw valid conclusions.
To fix this, Jamie should randomly assign participants to both the experimental and control groups, ensuring that any differences observed in time management are due to the treatment rather than other factors.
