2012 Unit 3 Question Thread.

[monkeywantsabanana]

Hey, can anyone explain descriptive and inferential statistics?

Descriptive statistics are used to analyse, organise and summarise important features of data so they are more easily interpreted. This includes:
• Mean - the average
• Median - the middle value
• Mode - the most occurring value
+ a whole range of charts, tables, diagrams,

Inferential statistics are mathematical procedures used to judge whether the results for a sample would also occur in the population and used to estimate how likely the results occurred by chance. These are your T-tests, P-values...
 

[orangejuice]

hey guys, was wondering what is the difference between stratified sampling and stratified-random sampling?

Basically, in stratified sampling once you've split up your population into various segments (i.e. strata) based on a particular characteristic then you need to actually pick participants from each segment. This procedure might be random (giving everyone an equal opportunity to be selected), it might be biased (purposefully picking people who are more likely to support your hypothesis), it might be convenient (pick whoever is available)... Now with stratified-random sampling it involves splitting up the population and then randomly picking participants from each segment.. Whilst with stratified sampling it involves splitting up the population and then picking participants but the selection technique used may be any of the three outlined above (random, biased or convenient)...

So basically stratified random sampling is just giving you more information about the sampling procedure and is more specific than the broader term "stratified sampling" which can incorporate a few different features.

thankyou It makes much more sense now!

[betruetoyou22]

heyy just wondering what the point of research methods is - like do we need to full on memorize the content ?? also section c of the exam is that just for the first exam or for both??

[Slumdawg]

heyy just wondering what the point of research methods is - like do we need to full on memorize the content ?? also section c of the exam is that just for the first exam or for both??

Yes, you must memorise the content. Research methods will feature on both your exams so make sure you understand it properly and learn all the topics... Research methods questions are typically application based, so there's very little regurgitation of information and a lot more applying your understanding to a unique scenario/experiment.

Section C will feature on both your exams as well, ranging from 10-15 marks.

[Scooby]

Hey, what are the advantages/limitations of random-stratified sampling compared to stratified sampling?

[emily_year11]

This is not entirely unrelatable to the subject, but I have a question.

I've done 2 SAC's so far for Unit 3 (Stroop Effect ERA and Consciousness/Sleep/Brain and CNS) and i've gotten an A+ (which I found was 98%) and an A (which I believe to be mid 80s).

If I were to be consistent and get these kind of marks for the rest of the course, what would my study score be?

[lauren.kate]

im trying to divide unit 3 into eight sections for revision, any suggestions on how i could do this ?!

[ktrah]

im trying to divide unit 3 into eight sections for revision, any suggestions on how i could do this ?!

Possibly:
- Research methods
- States of consciousness
- Methods used to study sleep and alertness
- Other sleep stuff
- The CNS
- The PNS
- Memory formation and models
- Forgetting and improving memory

Could someone please clarify the three different experimental designs for me (repeated-measures, independent-groups, matched-participants)? If half the class surveyed someone with the questions from 1-20, and the other half of the class surveyed someone with the questions from 20-1, what experimental design would that be? Thanks in advance!

[Genericname2365]

Could someone please clarify the three different experimental designs for me (repeated-measures, independent-groups, matched-participants)? If half the class surveyed someone with the questions from 1-20, and the other half of the class surveyed someone with the questions from 20-1, what experimental design would that be? Thanks in advance!

To me that sounds like independent-groups, as I'm assuming the person doing questions 1-20 is in the control group?

Repeated-measures is where each participant is involved in both the experimental and control conditions of an experiment. Matched-participants is where pairs are selected based on important characteristics that both share, then one member is randomly allocated to either the control or experimental group. Independent groups is where each participant is randomly allocated to either the control or experimental group, and each participant is in one group only.

[ktrah]

Thanks for your response! We were all really confused because our experiment didn't actually have a control group, but today our teacher hinted that it was repeated-measures because the participants were involved in all the tasks.

[Genericname2365]

Can the parasympathetic and sympathetic nervous systems both be active at the same time?

[emilyhobbes]

yes, they can, it's just that one's normally more dominant 

[vashappenin]

Okay so i've done like 9 practise exams, and my average score is 87% (when i say practise exams, I mean I've printed out and done all relevant AOSs from the past study design from both unit 3/4 for each year, and I've done it from 2002-2010). Also, my overall sac score is 95% .
Is that good or not? If I keep going at this rate, what score would it get me for my midyear? (As in A+, A, B+, B, etc.)
Thanks (:

[Genericname2365]

Okay so i've done like 9 practise exams, and my average score is 87% (when i say practise exams, I mean I've printed out and done all relevant AOSs from the past study design from both unit 3/4 for each year, and I've done it from 2002-2010). Also, my overall sac score is 95% .
Is that good or not? If I keep going at this rate, what score would it get me for my midyear? (As in A+, A, B+, B, etc.)
Thanks (:

Well personally I'd guess A+ but I'm not an expert; perhaps you might be more likely to get a response in the Vic technical discussion board.

Could the Phonological Store or Articulator Control System subsystems of the Phonological loop in the working memory model have a chance of appearing in the exam? I'm guessing not because I've never even seen them in the Grivas textbook (only in a powerpoint my teacher made), but I'm checking just in case. 

[ktrah]

Lol never heard of them so I highly doubt it.