2011 VN'ers Psychology U3 Questions Thread

[Glockmeister]

It's a confusing question, imho.

[iNerd]

During stage 3 of NREM sleep the brain waves are predominately _____________ waves?
A   Alpha
B   Beta
C   Delta
D   Theta

Err isn't it D? Answer says C....

[Camo]

In stage 3 Delta and Theta both occur but only 20-50% of the time for Delta? So most likely D? Referred to from the Cambridge text book.

[iNerd]

Yeah that was my reasoning.

Stupid LisaChem (04) exam :buck2:

[azngirl456]

In terms of the VCAA's unit 3 exam specifications and sample questions evaluative research section...how are we supposes to comment on p values? Do we have to mention all six they provide us and conclude that the experiment lacks internal and external validity?

[buzzwith]

Hi,

Can someone please explain internal consistency?

+ how: a measure can be reliable even though it's not valid, but a measure cannot be valid unless reliable ..

Thankss.

[iNerd]

Alrighttttey.

Internal consistency: are you testing what you're wanting to test? Basically if I give you a test for your personality and it consists of Specalist Maths questions there is no internal consistency at all.

If i give you a piece of string and ask you to measure using it a ruler but the ruler started from 1 cm and not 0cm your results are NOT GOING TO BE VALID, but they will be reliable because each time your using the same 'invalid' ruler.

[Glockmeister]

In terms of the VCAA's unit 3 exam specifications and sample questions evaluative research section...how are we supposes to comment on p values? Do we have to mention all six they provide us and conclude that the experiment lacks internal and external validity?

Put simply, all you need to know is this.

p > .05 - not significant.
p < .05 - significant.

This is a simplification, but is probably enough for VCAA purposes.

Significance has nothing to do with validity nor reliability. It merely refers to the probability of getting that the values that the study got, given that the null hypothesis is correct.

Alrighttttey.

Internal consistency: are you testing what you're wanting to test? Basically if I give you a test for your personality and it consists of Specalist Maths questions there is no internal consistency at all.

That's validity, ATAR, not internal consistency.

Internal Consistency is a type of measure used to examine reliability. Reliability refers to the ability of a particular test/technique to replicate the same or similar result over and over again. Internal Consistency in particular, is a measure of the degree of which similar questions in a test end up with similar answers. If a test is to be reliable, it makes sense that questions that ask similar topics, for example a question saying 'I like stuyding' and 'I enjoy studying' in a survey, should get similar answers.

Is Internal Consistency part of VCE Psychology? Back in my day (I feel old ), we only had to know reliability, and validity (external and internal). And I think that was Unit 1.

[azngirl456]

In terms of the VCAA's unit 3 exam specifications and sample questions evaluative research section...how are we supposes to comment on p values? Do we have to mention all six they provide us and conclude that the experiment lacks internal and external validity?

Put simply, all you need to know is this.

p > .05 - not significant.
p < .05 - significant.

This is a simplification, but is probably enough for VCAA purposes.

Significance has nothing to do with validity nor reliability. It merely refers to the probability of getting that the values that the study got, given that the null hypothesis is correct.

Alrighttttey.

Internal consistency: are you testing what you're wanting to test? Basically if I give you a test for your personality and it consists of Specalist Maths questions there is no internal consistency at all.

That's validity, ATAR, not internal consistency.

Internal Consistency is a type of measure used to examine reliability. Reliability refers to the ability of a particular test/technique to replicate the same or similar result over and over again. Internal Consistency in particular, is a measure of the degree of which similar questions in a test end up with similar answers. If a test is to be reliable, it makes sense that questions that ask similar topics, for example a question saying 'I like stuyding' and 'I enjoy studying' in a survey, should get similar answers.

Is Internal Consistency part of VCE Psychology? Back in my day (I feel old ), we only had to know reliability, and validity (external and internal). And I think that was Unit 1.

so you cant conclude anything else from p values other than whether results are significant or not significant?

yes, internal and external consistency are in the new study design

[iNerd]

Internal consistency refers to the interrelatedness of items in a psychological test in measuring the same ability or trait.

Err what? I thought that meant if your testing personality you got to have personality Qs...not something outrageous like Spesh qs.

:S

[Russ]

so you cant conclude anything else from p values other than whether results are significant or not significant?

You can get a bit more info out of them statistically but nothing important

[azngirl456]

so you cant conclude anything else from p values other than whether results are significant or not significant?

You can get a bit more info out of them statistically but nothing important

But let's say that the p value for the results of some drug is insignificant...wouldn't that mean that you wouldn't be able to use that drug on the general population...hence you need to change the drug to produce results which are significant?

[buzzwith]

so you cant conclude anything else from p values other than whether results are significant or not significant?

You can get a bit more info out of them statistically but nothing important

But let's say that the p value for the results of some drug is insignificant...wouldn't that mean that you wouldn't be able to use that drug on the general population...hence you need to change the drug to produce results which are significant?

If it's insignificant, couldn't you just write:
-Results are not statistically significant since p > 0.05
-the difference between the groups is unlikely to be due to the IV, but likely do to chance
-the experimental hypothesis is rejected; the null hypothesis is supporeted,

Or do could they ask you what can be done to change the results to significant? =S

[Glockmeister]

so you cant conclude anything else from p values other than whether results are significant or not significant?

You can get a bit more info out of them statistically but nothing important

But let's say that the p value for the results of some drug is insignificant...wouldn't that mean that you wouldn't be able to use that drug on the general population...hence you need to change the drug to produce results which are significant?

If it's insignificant, couldn't you just write:
-Results are not statistically significant since p > 0.05
-the difference between the groups is unlikely to be due to the IV, but likely do to chance
-the experimental hypothesis is rejected; the null hypothesis is supporeted,

Or do could they ask you what can be done to change the results to significant? =S

Pretty much your dot points.

There's no way you can turn a non-significant result to a significant data without either fudging the data to fudging the statistics, both of which are scientific no-nos (although the latter does get done more often than not).

[Glockmeister]

Internal consistency refers to the interrelatedness of items in a psychological test in measuring the same ability or trait.

Err what? I thought that meant if your testing personality you got to have personality Qs...not something outrageous like Spesh qs.

:S

Well, no (and I should know this, I've just submitted a lab report at uni where I actually had to test for internal consistency, so I'm pretty familiar with the process).

For example, if you're taking something like a personality test, you should expect that similar questions should get similar answers. So if you have two questions in a personality test which both are supposed to measure extroversion, then you would expect that a person should get similar answers to both questions. This is a reason why it is a form of reliability test - questions which measure similar constructs need to be consistently getting similar scores.

yes, internal and external consistency are in the new study design

Checked the study design again. You're right. Although don't think external consistency is in the study design, given that it doesn't exist.