Friday, 25 September 2015

Theme 4: Quantitative research

Pupil responses to continuous aiming movements


Which quantitative method or methods are used in the paper? Which are the benefits and limitations of using these methods?

The method in the paper is comprised of letting 14 participants use an apparatus with a one-handed grasper that is used to make motor actions inside an illuminated box. The inside of such boxes are recorded by a camera and displayed on a monitor. Surgeons use this kind of boxes when training endoscopic techniques.
The participants had to move the grasper back and forth horizontally between two circles on a paper in the box. There were three difficult levels, as shown in the image below, where the hardest was the top one and the easiest was the bottom one.
An eye-tracker was used—together with a camera to see when the participants were blinking or tilting their heads—to track how their pupils dilated during the total of 120 horizontal movements, divided equally between the three difficulty levels, each one of them did.

To make perceptual load be a non-factor and enable motor task workload to be the main factor of pupil dilation the researchers let the participants practice the task for a while before starting the real test. This way the participants were already familiar with the target setting, and this setting was never changed during the tests.
The tests were performed in a well controlled environment with minimal outer stimuli and constant lighting as to not affect pupil dilation.

Since all of the 14 participants performed the task 120 times each (1680 times in total), the researchers had room to discard “corrupted” data (e.g. when a person tilted their head and eye-tracking was off), and noise and factors affecting the pupils dilation averaged to zero thanks to the quantity of data collected.

What did you learn about quantitative methods from reading the paper?

By reading this paper I learned that there was so much preparations and discussions about how to interpret the data in the best possible way before they could make use of the data and show their results with any certainty.
I think that the most important part of research by quantitative methods is the preparation part; you must read up on your theories, think about what data you want to collect, how that data is to be collected as efficiently as possible and make sure that the method you will be using produces as much data as to enable you to come to a conclusion with good enough statistical certainty.

All of the decisions and steps made are brought up in the paper as to not make the readers guess why a certain procedure was chosen or how an intermediate step was conducted, which is good to have in mind when writing a paper.

Which are the main methodological problems of the study? How could the use of the quantitative method or methods have been improved?

Since only 3/14 of the participants were female, I think they could have had more female participants.

Maybe they should have let the participants go through some tests to see if their pupils’ dilation were normal in terms of speed and diameter, and then take this into account when analyzing the main data. But maybe it’s enough that they had so much data from each participant from the test they did that all minor differences between participants were averaging to zero. Yeah, I believe that’s the case.

All in all I think that the methods were superb.

Drumming in Immersive Virtual Reality: The Body Shapes the Way We Play


This article is an example of a good usage mix of quantitative and qualitative methods. The methods are explained in an easy to follow way since it is chronological and every component has adequate space in the text. It is interesting how it is concluded that humans so easily can feel they are in ownership of another body and take on the abilities we think that body should have.

Which are the benefits and limitations of using quantitative methods?

By using quantitative methods you don’t for example get extra info from participants because you don’t conduct free form interviews or free text questions in questionnaires; you only gather the data you decided beforehand was important to get. This data is easily analyzed by computers, mathematics and statistics and you can therefore gather a lot of “raw” data with this method. When the data has been analyzed it can be generalized because it is, hopefully, unbiased.
You could say that quantitative methods seek to answer what, where, when; empirical research.

Which are the benefits and limitations of using qualitative methods?

Qualitative methods seek to answer the why and how of what is researched.
Using qualitative methods let’s you get a deeper understanding of a particular thing, but it is harder to generalize since general conclusions based on qualitative methods are seen as hypotheses.

References:

Jiang, X., Zheng, B., Bednarik, R. & Atkins, M.S., 2015 Pupil responses to continuous aiming movements
Available at:
http://www.sciencedirect.com/science/article/pii/S1071581915001007

1 comment:

  1. You really well explain your research paper! And I agree with you when you said that the most important part in quantitative methods is the preparation one. Indeed, if you well design your study, it would be easier for you to interpret correctly the results.
    As I said, you did a good job, but I would have liked you to be more critical about the problems of the study. Indeed, don’t you think that the number of participants is too weak to come up with relevant results? I do think that 14 participants are not enough to manage a good study. Don’t you agree?

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