There are many extraneous variables within our experiment that must be controlled in order to achieve a fair test. They are listed below and also how to control them best is explained: Intelligence: Since it will be impossible to find a group of participants that are all of equal intelligence and mathematical ability – some participants may turn out to be better than others at solving the problems and this can therefore affect our results. In order to regulate this a well as possible we will be using opportunity sampling in order to select participants as fairly as possible without any bias towards a particular group.
Males and females will also be used in equal numbers from the people we select. Sampling: The most suitable method of sampling that we have came up with for our experiment is OPPORTUNITY SAMPLING. We will actually use the available people at the time the experiment is to be carried out. This will ensure that no bias will be made towards a particular group. We will select an equal number of males and females also to ensure no bias are made in the sex of the participants.
We have chosen opportunity sampling over random sampling due to the fact that random sampling will result in an undeterminable selection of males and females from various ages and educational backgrounds – opportunity sampling will allow us to select participants from the target population and age levels we wish to test since we are using participants from an A-level class. Distraction: We must ensure that whilst the participants are taking part in the experiment that there is as little distraction as possible in the area.
To ensure this, each participant will go individually into a silent room to take part in the experiment whilst the others wait outside. Communication between participants: Because we have decided to send each participants in to the experiment one by one, we must ensure that NO communication will take place when one participant leaves and another enters. To prevent this we will keep the participants that have yet to take part in a separate room from the corridor that leads to the testing room. This will ensure that no answers to the test may be passed between participants.
All these factors will be controlled to the maximum level they can be in order to ensure as fair a test as is possible. Target Population: Our target population will be males and females between the ages of 18 and 21 living in Belfast, Northern Ireland. They will be all be chosen using opportunity sampling from pupils within and A-level psychology class. Welcome and thank you to you all for agreeing to take part in this experiment. Before we start, I would like to explain a bit about what we are going to do today and then I’m hopefully going to answer some of the questions you may have in regards what you are to do.
First I would like to inform you of the nature of this experiment and what will happen. To begin you all will be chosen randomly one by one to take part. Then you will be led to the testing room, where you will find a tape recorder, two sheets of paper and a pen. I would ask you not to touch any of these items until you are told to do so. You will then be asked to put the earphones on and to turn over one of the sheets of paper – where you will see a series of twenty sums. When you are ready to begin, simply press ‘PLAY’ on the recorder and attempt to complete the series of sums.
What you will hear from the recorder you are not to pay attention to, but you are to only concentrate on completing the sums. When the recording stops and you are asked to stop writing, please do so. Take a few seconds to compose yourself if you wish and then attempt the second set of sums. Make sure you do NOT have the recording playing whilst doing this. When you are asked to stop, please do. You will then be shown to the debriefing room where you may enjoy some refreshments and relax while you wait until all the participants have finished until you are debriefed.
Once again, thank you for your time and co-operation and I must know inform you that you do have the right to remove yourself from the testing at ANY time. If you feel in anyway that you want to leave, then leave immediately, there is no restrain or pressure on you at any time to stay. Thank you. If you have any questions, please raise your hand and I will help you with your enquiry but I regret I cannot answer any questions regarding what we are expecting from testing you – this may affect our results, but all will be explained in the debriefing after you all have finished the experiment.
Thank you all. ” Debriefing: ” Thank you all for taking part in this experiment. I hope we have not inconvenienced any of you in any way and I will now go about explaining what we have just done. Each of you were asked to complete two sets of sums, one set with random numbers playing in your ear, one set without them playing. The purpose of this was to see if the presence of the random numbers had any effect on your number of correct answers. We wish to investigate what the effects are of distracting noise on a human’s attention and by this experiment today we hope to further our knowledge.
You may have noticed that the two sets of sums were the exact same only rearranged in a different order. This was to help us achieve a fair test. By rearranging the sums, we gave you the illusion that you were doing a new set of sums but in actual fact you were doing the same sums again. If we had have used a new set of sums, it would’ve been difficult to make a new set that were as easy or as difficult as the first set – by using the same sums, we ensure a fairer test. Once again I thank you for taking part and for your co-operation in our experiment. If you have any questions whatsoever, please ask.