In: Statistics and Probability
An animal psychologist wanted to determine whether fish can remember things over a period of time. Fifty goldfish were randomly assigned to one of two groups- Group A and Group B. Group A was placed in a trap, inside their tank, and food was placed outside the trap (to motivate the fish to want to get out of the trap). On the average, it took 45 minutes for the fish to figure out how to escape the trap. Group B was given no experience of the trap.
Six months later, both groups were placed the same type of trap. On the average, it took group A fish 3 minutes to escape from the trap, while it took group B fish 45 minutes. The researchers concluded that the Group A fish had been able to remember how to escape from the trap for six months.
Answer TRUE or FALSE to each statement below:
Group A is the control group. TRUE FALSE
This is a designed experiment (controlled experiment). TRUE FALSE
This study will probably have a problem with response bias. TRUE FALSE
This study uses a placebo. TRUE FALSE
1. Group A is the control group FALSE
Reason: Group A is Experimental group because treatment is being given to group A, where group A fishes were placed in a trap, inside their tank, and food was placed outside the trap. Experimental group is a group which do not recieve treatment in an experiment.
Whereas Control group is a group on which actual treatment is not given and including a control group helps in making conclusion if an experiment is significantly working on experimental group or not. In this case Control group is Group B which is not given any experience of trap.
2. This is a designed experiment (controlled experiment). TRUE
Reason: A controlled experiment is an experiment or test done in controlled conditions. In this experiment only one or few factors are changed. In this case, placing fish in trap and keeping food outside are the factors/treatment which are given to group A and not group B.
3. This study will probably have a problem with response bias. FALSE
Reason: The fishes were randomly selected for two groups A and B. And factors are given to group A and not group B. So the study will not have any response bias as the fishes are selected randomly, therefore removing the hidden bias from experiment.
4. This study uses a placebo. FALSE
Reason: In placebo effect we give a substitute of the treatment like for example where people get better simply because they think they’re getting treated by fake medicine/drug. In this case, group b in given no experience of trap or fake trap. So, this study doesn't use placebo effect.