Reliability & Validity

[emiinaaa]

Can someone please explain to me what is meant by reliability, including internal consistency, and validity, including construct and external?? With an example or something, since I don't really understand what is meant by it in my notes, especially construct validity..

Thanks in advance

[vagrantshades]

Reliability is the consistency of the experiment / instrument.

Internal reliability refers to how consistent the items within the experiment / instrument all relate to each other and if they are all equally testing the same thing. For example, if you're given a questionnaire about sleep deprivation, if it has internal reliability, all of the questions should relate to sleep deprivation.

Construct validity refers to if the method of the experiment / instrument reflects the theory that is desired to be tested. For example, if you're testing the theory that there is a capacity of 5 - 9 items in short-term memory, your experiment will have construct validity it is designed in a way that supports this theory, and isn't instead testing the duration of short-term memory.

External validity refers to if the results of the experiment can be appropriately generalised to the population and other similar research/studies.

Does that make sense?

[emiinaaa]

Reliability is the consistency of the experiment / instrument.

Internal reliability refers to how consistent the items within the experiment / instrument all relate to each other and if they are all equally testing the same thing. For example, if you're given a questionnaire about sleep deprivation, if it has internal reliability, all of the questions should relate to sleep deprivation.

Construct validity refers to if the method of the experiment / instrument reflects the theory that is desired to be tested. For example, if you're testing the theory that there is a capacity of 5 - 9 items in short-term memory, your experiment will have construct validity it is designed in a way that supports this theory, and isn't instead testing the duration of short-term memory.

External validity refers to if the results of the experiment can be appropriately generalised to the population and other similar research/studies.

Does that make sense?

Yesss it does now, thanks!

[joseph95]

Vagrantshades, am I reading incorrectly, or do you have 4 mid-years in the next two days?!?!?! And you want very high 40s for all of them? You must be very confident haha

[pubsquash]

do we have to know internal validity even though its not on the study design?

[vagrantshades]

I'd doubt it, the study design is a good indication of what the examiner's will put on the exam, but if you want to be safe you can also memorise it.

[ecvkcuf]

sweet! not gonna memorise it then.
ty

[vagrantshades]

Vagrantshades, am I reading incorrectly, or do you have 4 mid-years in the next two days?!?!?! And you want very high 40s for all of them? You must be very confident haha

Haha yes I do have 4 mid-years in the next two days. Two down two to go! I'm a science nerd.

[joseph95]

Vagrantshades, am I reading incorrectly, or do you have 4 mid-years in the next two days?!?!?! And you want very high 40s for all of them? You must be very confident haha

Haha yes I do have 4 mid-years in the next two days. Two down two to go! I'm a science nerd.

Haha how'd you go?

[vagrantshades]

Vagrantshades, am I reading incorrectly, or do you have 4 mid-years in the next two days?!?!?! And you want very high 40s for all of them? You must be very confident haha

Haha yes I do have 4 mid-years in the next two days. Two down two to go! I'm a science nerd.

Haha how'd you go?

1 mark lost in Physics, 1-2 in Chem, 1-3 in Bio and 2-3 in Psych...so alright I guess? Hopefully I can do well on the end-of-years and maybe I can nab the ATAR I'm hoping for!