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Everything posted by blindpet

  1. blindpet

    EE Psychology

    You can do an EE on criminal psychology but I would make sure to include cognitive, biological and social approaches to the specific topic. I had teachers like that, get back on them and demand an answer, that is what they are paid for You do not have to do an experiment for the EE so your friend is mistaken (unless the syllabus has changed), you can check the EE guidelines for Psychology.
  2. blindpet

    Psychology IA

    I think you can add your draft here and see if anybody can provide feedback for you. You may also want to consider hiring a tutor if you would like in-depth feedback. Please also consider complaining to your teacher about the lack of constructive feedback, if s/he won't do anything to fix it then talk to your IB Coordinator.
  3. blindpet

    Psychology IA urgent help needed

    In a repeated measures design, the control group is the same group of people but it is called the control variable and you compare those results to the experimental variable. I am not familiar with that study but in a repeated measures design it works like this: You find a group of people Group of people all do the same experiment under condition 1 (this is the control in many cases) Group of people all do the same experiment under condition 2 (this is the experimental condition or where you changed a variable and are interested in its effects compared to how they performed in condition 1) The correct test to use in your case would be the repeated measures or within group t-test (not the mixed group or independent t-test) https://statistics.laerd.com/statistical-guides/dependent-t-test-statistical-guide.php There is an online tool you can use to get your data http://www.statskingdom.com/160MeanT2pair.html
  4. blindpet

    Will replication of Asch for IA be acceptable?

    Do not use Asch, it's pretty clear from the ethical guidelines for IA that the study isn't allowed. Stroop is the easiest to carry out at short notice in my opinion.
  5. blindpet

    Using abbreviations in psych exams

    Abbreviations are fine if they are used correctly. The first time you mention the word you want to abbreviate it should be in parentheses e.g. participants (P's) which communicates it properly. I would suggest making the abbreviations capital so they stand out a bit more. If your abbreviations affect the readability for the examiner then it could cost you marks.
  6. If the source doesn't cite the articles I would find another source, how can you trust a source that lists no sources? If multiple sources are referenced the you go find those sources and see which one is the most likely/relevant
  7. You should ideally only cite proper journal articles. Most wikipedia or other articles will link to the original source articles in journals.
  8. Fisher's exact test would be good and is what is used elsewhere for the same research http://www.fitelson.org/probability/wason.pdf You shouldn't lose marks but it will take up words so you should be mindful of that as you will not get marked up for including Fisher's test (it's not part of any assessment criterion). The table will show the distribution of scores which is the best you will get for your nominal data.
  9. Which research are you replicating? What were your independent and dependent variables? You can still get the spread by doing the average of the data (it will be between 0 and 1) so you'll get a standard deviation, of course showing a table of the distributed yes and no will be much easier for the user to read, that table shows the spread of data. With binary choice data you can use chi squared or logistic regression but they are beyond the scope of psychology SL I believe.
  10. blindpet

    Biology and cognition - is it an 8 or 22 marker?

    It is clearly laid out in the syllabus which command terms are used for LAQs and Explain is not one of them.They do mention in the syllabus that SAQ command terms can be applied to LAQ command term questions, however this isn't really a problem since the SAQ command terms do not require more knowledge to answer than the LAQ ones.
  11. blindpet

    Inferential Statistics, please help

    It has been a while since I did it manually but that sounds right, if t is higher than critical value then the null hypothesis is rejected (for some statistical tests the critical value needs to be less than).
  12. blindpet

    Inferential Statistics, please help

    Tails refer to the direction of the hypothesis. When you have clear theoretical reasons to predict one condition will be greater than another then you use a one-tailed test. When you have no theoretical grounds and just assume there will be a difference then you use a two-tailed test. http://www.ats.ucla.edu/stat/mult_pkg/faq/general/tail_tests.htm
  13. blindpet

    Inferential Statistics, please help

    You're welcome, good luck
  14. blindpet

    Inferential Statistics, please help

    37 participants sounds large enough to use a t-test instead of the wilcoxon non-parametric version.
  15. blindpet

    Inferential Statistics, please help

    There is not much to explain, the repeated measures t-test examines the variance between the means between the first trial and the second trial and looks up the value it returns in a table to calculate the probability the results occurred from chance. If the p value is small enough you conclude the results did not occur from chance and instead from the treatment manipulation you used in your experiment.
  16. blindpet

    Inferential Statistics, please help

    There are multiple versions of the t-test, there is one for independent measures and one for repeated measures.
  17. blindpet

    Inferential Statistics, please help

    Your teacher should explain to you that this is a within subjects design, also called a repeated measures design. Your data are interval/ratio since they are times and have an absolute 0 (meaning 0 actually means no time taken). You can use a related t-test for your data to get the p-value. If you have a small sample size you can use the Wilcoxon t-test, even though it is a non-parametric test (for ordinal data like rating the attractiveness of a person out of 10), it can be more robust for small sample sizes with interval/ratio data. You can justify the use of either test, there are online calculators that will return the right values. Remember to report the mean and standard deviation when making your tables and graphs and the p value from the inferential test. Good luck!
  18. You didn't mention which design you used but it looks like it was repeated measures. Your data are ordinal so a t-test is not appropriate. If it was a repeated measures test (all participants rated all of the photos) then you should use a Wilcoxon t-test. If it was independent measures (between subjects), then you should use the Mann Whitney U test. These are just to look for differences between the groups (if you wanted to look for interactions then you would use the Kruskal Wallis or Friedman's test). You mentioned you were looking for a correlation in which case you should use Spearman's Rho since your data are ordinal (it is the non-parametric equivalent of the Pearson test). For Spearman's you would run the raw data and not the means, plot the data and report the correlation coefficient.
  19. @Caramell sounds like you looked at correlation which would be Spearman's rho testing (it is the Pearson's correlation equivalent for non-parametric data i.e. for ordinal data). Then again I do not know the details of your study, initially you mentioned the General Linear Model, perhaps your teacher used an ANCOVA. It would help if you laid out simply the design of the experiment and all the measures taken.
  20. I honestly think the IB may be suspicious if students are using SPSS for statistics. That is a university level statistics software that I used in my bachelor's and master's program. Things may have changed though. If I were you I'd use a simple t-test like I have seen most Psych HL IAs use.
  21. blindpet

    Help with Psychology IA

    You probably measured speed of the car which is technically an interval/ratio data level so the appropriate test would be a t-test. However, because you probably have a small data set then tests for ordinal data like Mann Whitney are justified as they tend to be less likely to give false positives (it is usually harder to get a small p value for Mann Whitney compared to a t-test). That is the justification I would use. Basically the choice of inferential test depends on the design (indpendent vs repeated measures) and the measurement level of the data (interval/ratio, ordinal, nominal) as well as the sample size.
  22. General Linear Model sounds more advanced than necessary for IB Psychology. Generally a simple t-test will suffice or Mann Whitney test. ANOVAs are something you learn in university Psychology programs. The purpose of inferential statistics is to provide a probability that the results you got could have occurred from chance. The smaller your probability (p level) the less likely it is your results occurred due to chance. You do not use graphs for inferential statistics p level reporting, you report the means, standard deviation and p level, then you use your descriptive statistics for the data visualization in a graph.

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