Explain the factorial design of the experiment. In doing so, list all the factors (independent variables) and how many levels each factor had

KTS Assessment 1: Experiment Design

General instructions: In answering the questions, please use bullet points where appropriate. There is no need to write long continuous text. Please use the text boxes to provide your answers in Calibri, font size 11. The text boxes should be large enough for the answers, so please make sure your answers are concise.

Section 1: Experiment Design I

Please read the paper by Steggemann et al. (2011) and analyse the experimental design of the study. The paper is available on Brightspace and here: http://www.kai-engbert-sportpsychologie.de/fileadmin/user_upload/pdfs/Publikationen/YBRCG2678.pdf

l  Steggemann, Y, Engbert, K, Weigelt, M (2011). Selective effects of motor expertise in mental body rotation tasks: comparing object-based and perspective transformations. Brain Cogn, 76, 1:97-105.

Answer the following questions:

Question 1: Experiment 1 consisted of 320 trials (Steggemann et al. 2011). Explain the factorial design of the experiment. In doing so, list all the factors (independent variables) and how many levels each factor had (5 Points).

Question 2: Explain why the main response time analysis in Experiment 1 (Steggemann et al. 2011) focused on correct trials only. In doing so, explain why in response time experiments it often makes sense to omit trials in which participants responded incorrectly from the further analysis (3 points).

Question 3: Explain possible reasons for why the authors (Steggemann et al. 2011) decided to exclude trials with a response time shorter than 300 msec and longer than 3000 msec from the further analysis in Experiment 1 (3 points)

Question 4: We discussed the design and the analysis of the seminal study by Shepard & Metzler (1971) in detail in the second KTS session. Shepard & Metzler (1971) only analysed 50% of the trials, i.e. only those trials which depicted two identical objects. In contrast, Steggemann et al. (2011) analysed all trials, i.e. trials which depicted two identical pictures/objects as well as trials which depicted two different pictures/objects. Explain, why Steggemann et al. (2011) could analyse all trials, while Shepard & Metzler (1971) had to restrict their analysis to the trials depicting two identical objects (3 points).

l  Shepard, RN, Metzler, J (1971). Mental rotation of three-dimensional objects. Science, 171, 3972:701-3 Explain the factorial design of the experiment. In doing so, list all the factors (independent variables) and how many levels each factor had

Section 2: Experiment Design II

Read the study by Röser et al. (2016) and analyse its design: The study is available here: https://link.springer.com/article/10.1007%2Fs00221-016-4582-z (open access if you access it from a University Computer) and on Brightspace.

l  Röser, A, Hardiess, G, Mallot, HA (2016). Modality dependence and intermodal transfer in the Corsi Spatial Sequence Task: Screen vs. Floor. Exp Brain Res, 234, 7:1849-62.

Röser et al. (2016) tested each participant in four different so-called “modality conditions” (screen-screen; screen-floor; floor-screen; and floor-floor). Answer the following questions:

Question 5: Explain how Röser et al. (2016) addressed potential order effects, originating from the order in which the four different modality conditions (screen-screen; screen-floor; floor-screen; and floor-floor) were presented to participants, and discuss the advantages/ disadvantages of their approach (5 points).

Question 6: Explain why, given the number of participants tested, Röser et al. (2016) could not have used a fully balanced design, which would have controlled for the order in which the conditions were presented (2 points).

Question 7: Discuss at least two alternative ways of dealing with potential order effects that Röser et al. (2016) could have used (5 points).

Section 3: Experiment Design III

Question 8: Assume you have run a study with a within factor that had three levels (Condition 1, Condition 2, Condition 3). While each participant was tested in all conditions, you are missing data from 3 participants in one of the conditions due to technical problems during data collection. You plan to analyse the data in a repeated measures ANOVA. Describe two different ways of dealing with the missing data, and explain their advantages/ disadvantages (4 points)

Question 9: Explain why many cognitive psychology experiments test the same conditions (or factor combinations) multiple times (for example, Steggemann et al., 2011) instead of relying on a single measurement (3 points).