Hey guys would really appreciate if the question is answered in full! Really hel
ID: 3270002 • Letter: H
Question
Hey guys would really appreciate if the question is answered in full! Really helps me a lot and positive ratings for correct answers thanks in advance.
Problem 1 [12 marks] Sleepeze is a new drug that is claimed to reduce insomnia. You plan to conduct an experiment to test this claim. You are given resources to monitor a total of 120 person-nights (that is, 120 people for one night each, or 60 people for two nights each, or one person for 120 nights, etc.). For each of the six experimental principles (replication, control, blinding, blocking, balance and ran domisation), explain how they might be achieved in this study specifically, OR why they should not be applied. [2 marks each
Explanation / Answer
The detail of experimental design study is as follows.
Sleepze is a new drug that is claimed to reduce insomnia. 60 people were recruited for the study. The people were randomly divided into two groups. One group is a control group and was given a placebo (drug with no effect) instead of Sleepze drug and the number of hours of sleep was recorded. Second group was given Sleepze drug and the number of hours of sleep was recorded. Comparisons of the number of hours of sleep was done to check the claim that new drug reduce insomnia.
All six principles except blocking were followed by the above experiment.
Replication - Replication is the repetition of an experimental condition so that the variability associated with the phenomenon can be estimated.
For each of the two groups, the experiment were carried on 60 individuals. So there was repetition of the experiment 60 times for each group.
Control - The control group (sometimes called a comparison group) is used in an experiment as a way to ensure that your experiment actually works. The experimental group is given the experimental treatment and the control group is given either a standard treatment or nothing.
In the experiment, there is a control group which is given placebo (a drug with no effect).
Blinding - A blind—or blinded—experiment is an experiment in which information about the test is masked (kept) from the participant, to reduce or eliminate bias, until after a trial outcome is known.
In the experiment, each individual was not informed whether he/she has given a placebo or Sleepze drug.
Blocking - In the statistical theory of the design of experiments, blocking is the arranging of experimental units in groups (blocks) that are similar to one another. It is used when the experiment has only two treatment conditions; and participants can be grouped into pairs, based on some blocking variable. Then, within each pair, participants are randomly assigned to different treatments.
Although blocking was not used in the above experiment. But it can be used to check the effect of the drug on other variables such as Age or Gender of the individual. The individuals can be grouped based on the age/gender and then each groups are assigned to both the treatment conditions to check the effect of drug on insomnia for different genders and age groups.
Balance - An experiment is balanced when all factor levels (or treatment groups) have the same number of experimental units (or items receiving a treatment).
In the conducted experiment, both groups have the same number of individuals (60) assigned. So the experiment is balanced.
Randomization - Randomization is a random process of assigning treatments to the experimental units.
After the participants have been recruited, they should be randomly assigned to their groups. This should ensure the groups are similar, on average (reducing participant variables).
In the experiment, the people were randomly divided into two groups for the treatments.