Skip to main content

Why is it important to control variables in an experiment?

It is important to make sure that when conducting a controlled experiment to test an hypothesis, all the variables are the same in two test groups except for the independent variable.


In a controlled experiment, the group that is testing the independent variable is called the experimental group. The other group that does not test this variable is called the control group. By comparing both groups, one can see the effect (if there is one) of the independent variable on the research. How the group reacts to the independent variable is called the dependent variable. 


All other variables in each group are kept the same. This will allow the researcher to see if the tested variable is responsible for a result in the research.


For example--a researcher may wish to test the hypothesis that exercise before an exam will result in higher test scores. The independent variable is exercise and the test scores are the dependent variable. Two groups are organized into an experimental or tested group and a control group. The experimental group gets to exercise for a pre-determined amount of time before taking an exam. The control group does not exercise and simply takes the exam.


However, all other variables are kept the same in each group--amount of participants, same exam, same room, same amount of males and females, same age group, etc. This will allow the researcher to see whether her hypothesis is accepted or rejected. 


I have included a link to the steps a scientist follows when conducting a controlled experiment.

Comments

Post a Comment

Popular posts from this blog

Is there a word/phrase for "unperformant"?

As a software engineer, I need to sometimes describe a piece of code as something that lacks performance or was not written with performance in mind. Example: This kind of coding style leads to unmaintainable and unperformant code. Based on my Google searches, this isn't a real word. What is the correct way to describe this? EDIT My usage of "performance" here is in regard to speed and efficiency. For example, the better the performance of code the faster the application runs. My question and example target the negative definition, which is in reference to preventing inefficient coding practices. Answer This kind of coding style leads to unmaintainable and unperformant code. In my opinion, reads more easily as: This coding style leads to unmaintainable and poorly performing code. The key to well-written documentation and reports lies in ease of understanding. Adding poorly understood words such as performant decreases that ease. In addressing the use of such a poorly ...
Post a Comment
Read more

Is 'efficate' a word in English?

I routinely hear the word "efficate" being used. For example, "The most powerful way to efficate a change in the system is to participate." I do not find entries for this word in common English dictionaries, but I do not have an unabridged dictionary. I have checked the OED (I'm not sure if it is considered unabridged), and it has no entry for "efficate". It does have an entry for "efficiate", which is used in the same way. Wordnik has an entry for "efficate" with over 1800 hits, thus providing some evidence for the frequency of use. I personally like the word and find the meaning very clear and obvious when others use it. If it's not currently an "officially documented" word, perhaps its continued use will result in it being better documented.
Post a Comment
Read more