IB Psychology Internal Assessment

The Task Replicate an experiment that manipulates an Independent Variable Write a report conforming to IB guidelines

Step 1: Choosing an experiment to replicate Guidelines: Ensure that the study has an IV that you can manipulate (not gender/age/culture) Your research question should be important. If you can not find at least a few sentences in a standard psychology text about the research you plan to replicate, think again. You must clearly justify your hypothesis.

Step 1: Choosing an experiment to replicate Guidelines: You cannot deceive, harm, or ask your participants to eat or drink any substances You are not expected to conduct a ‘perfect’ experiment

Step 2: Locating Sources Locate a copy of the original experiment Find at least 5 other studies (HL) Analyze all of these studies by breaking them down into research design elements, theory and conclusions Avoid too many internet sources

Step 3 Modifying the Research Design You will have to modify the original experiment Sampling Reduce the number of variables Simplify the DV Use a different statistical test to determine significance

Step 3 Modifying the Research Design cont’ Independent measures design Versus repeated measures design . (Be able to justify this in your report) Independent measures is usually best as you do not have to undertake counterbalancing to avoid the test-retest confounding variable

Step 4 Obtaining your sample of participants The ISL student body will be your target population (experiment fatigue) Randomly sample You can select an opportunity sample but you will have to justify why you did this An ideal sample is 50 students giving you two groups of 25. If you have some no-shows you will still have 20 per group

Step 4 Obtaining your sample of participants Signed informed consent forms must be obtained (You will provide a copy of the consent form in your appendix) Students younger than 16 will require parental consent You must keep all forms and ensure the confidentially of data You must collect relevant bio-data from the participants e.g. age, first language etc. You will report any relevant characteristics You must randomly assign participants to groups

Step 5 Ensuring Control The two groups in your experiment should be treated exactly the same except for the IV All instructions to the groups should be scripted to ensure they are identical All other conditions should be identical as far as possible Note any inadvertent differences in treatment and discuss in your report

Step 6 Ethical Considerations Remind participants that they are free to leave the experiment at any time Debriefing: All participants must be informed of the results of your experiment

Step 7 Analyzing the Data Use non-parametric statistical tests of significance (Mann Whitney U-test) Your small sample size prohibits parametric tests like the t-test. Use online sites to calculate Raw data and calculations should be included in the appendix

Writing Your Report You MUST follow the IB guidelines and use APA format. Common omissions: no abstract; data not displayed in three ways i.e. words, tables and graphs; sources not cited, no Works Sited page; no appendices (sample informed consent form, raw data, statistical test calculations, scripted instructions) You must write like a social scientist

Student Advice Do not underestimate the amount of time required to complete the IA Do not choose a study that is too obscure Scientific writing is “way harder” than you think Think about the best time to hold your experiment so that students will turn up Time management is the key It is okay if you do not accept your hypothesis