An experiment is set up to test whether a particular insect prefer a dark or a bright environment. A chamber with a gradient in light intensity from one end (dark) to the other (bright)
has been made. The experimental hypothesis is:
“There will be a large difference between the number of insect in a dark side and the number in a bright side of the chamber.”
decide for each of the following whether they are potential confounding variables?
A - Varying humidity across the chamber
B - The orientation of the chamber
C - The age of the insects
D - The non-reflective material from which the chamber is made
E - The type of light source used
F - Varying temperature across the chamber
any help, thanks
anything that is different at one end like F or A
What is a confounding variable?
"A confounding variable is a variable, other than the independent variable that you're interested in, that may affect the dependent variable. This can lead to erroneous conclusions about the relationship between the independent and dependent variables. You deal with confounding variables by controlling them; by matching; by randomizing; or by statistical control."
Yes, I think A + F could be confounding variables
probably not B + D + E
B does not change across the chamber
D is irrelevant
E is also irrelevant
probably not C, this does not change across the chamber
thoughts?
A + F = yes
perhaps also "B - The orientation of the chamber"
since this could change between one end of the chamber and the other?
? thoughts? orientation = up/down?
My personal opinion is that orientation make sno difference.
Also I think the type of light is relevant. A bright white light vs a yellow light vs a uv light I think would make a huge difference. I don't know about C since I don't know the behavior of young vs old insects. That might depend upon the kind of insect.
To determine whether each factor is a potential confounding variable, we need to assess whether it could influence the results of the experiment and potentially introduce bias or alternative explanations for the observed differences in insect distribution.
A - Varying humidity across the chamber: This factor could potentially influence the preference of insects for a dark or bright environment. If some insects are more attracted to humid environments, while others prefer drier conditions, it could alter their distribution in the chamber and confound the results. Thus, it could be a potential confounding variable.
B - The orientation of the chamber: The orientation of the chamber, such as its alignment with respect to light sources outside the chamber, could affect the distribution of light intensity. It might impact how insects perceive and respond to the gradient of light. Therefore, it could potentially confound the results, and thus, it is a potential confounding variable.
C - The age of the insects: The age of the insects might impact their preferences and behaviors. Some insects may favor bright environments when they are young and switch to prefer dark environments as they age, or vice versa. Therefore, age could influence the distribution of insects in the chamber and potentially confound the results. It is a potential confounding variable.
D - The non-reflective material from which the chamber is made: The material from which the chamber is made should not directly affect the insect's preference for a dark or bright environment. Therefore, it is unlikely to confound the results and can be considered a non-confounding variable.
E - The type of light source used: The type of light source used might influence the insect's perception of brightness or their attraction towards light. If different light sources have varying effects on insects' behavior, it could confound the results. Thus, it is a potential confounding variable.
F - Varying temperature across the chamber: Temperature can affect insect behavior, including their preference for a particular environment. If insects prefer the dark side due to its cooler temperature, it could confound the results. So, varying temperature across the chamber is a potential confounding variable.
In summary, the potential confounding variables in this experiment are A (varying humidity across the chamber), B (the orientation of the chamber), C (the age of the insects), E (the type of light source used), and F (varying temperature across the chamber). D (the non-reflective material from which the chamber is made) is not expected to confound the results.