1 / 3

Data Analysis

Data Analysis. Step 1 Add your data together for each stimulus level so that you have a total out of 60. The end column becomes the y-variable in Whizgraph It represents the proportion of rightward responses at each stimulus level. Data Analysis. Step 2

sarah-todd
Télécharger la présentation

Data Analysis

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Data Analysis Step 1 Add your data together for each stimulus level so that you have a total out of 60 The end column becomes the y-variable in Whizgraph It represents the proportion of rightward responses at each stimulus level.

  2. Data Analysis Step 2 Transform your stimulus levels to pixel units. A value of 4 = 0. Convention: left is negative and right is positive The transformed stimulus level becomes the x-variable in the Whizgraph

  3. Data Analysis Step 3 Fit a Logistic function to your data using Whizgraph  Y=100/1+e^(x-)/ Where y is the % of rightwards positional judgements,  is the offset corresponding to the 50% level (i.e. the Point of Subjective Alignment (PSA)), and  is an estimate of the alignment threshold (i.e. Positional Acuity (PA)). M1 - Point of Subjective Alignment (PSA) M2 - Positional Acuity (PA) Both of these values can be converted to units of visual angle by multiplying the value by the conversion factor. CV for WD of 57cms is 1.48422. CV for WD of 28.5.5cms is 2.96844. This will convert your PSA and PS measures to minutes of arc.

More Related