Lens Model Download

Description (by Henry Chen):

The code should work with an arbitrary (but computationally reasonable) number of observations (data points/judgments), cues, etc. Both the .m and .fig files are needed for Matlab. The .xls file (see below) is sample input data.

This Matlab program reads data from an Excel file (.xls) containing 1 Ss judgment data and generates a text file containing estimates of all 8 Skill Score/Lens Model parameters. The psychological meaningfulness of these parameters of course cannot be assured by the software itself (GIGO).

• First, create a spreadsheet: (e.g. spreadsheetformat.xls)
  
  1. Create a column for observation/trial/judgment number. (first column)
  
  2. Create a column for each cue value, with the number of rows equal to the number of observations. Adjoin the columns to create a cue matrix.
  
  3. Create a column for the environmental criterion values. (second to last column)
  
  4. Create a column for the human judgments. (last column)
  
  5. Each column assumes header text. An example .xls file is attached from 1 subject in an experiment where the S is asked to estimate the expected number of runs that would score in a baseball inning, where the cues are the location(s) of any potential runners on base and the current number of outs in the inning. The criterion values, expected runs, are based on 100 (+/-) years of published Major League Baseball data.



• Then, execute the file (thelensmodel.m). The outputs of the program are:
  
  1. Achievement (ra)
  
  2. Cognitive control (Rs)
  
  3. Environmental predictability (Re)
  
  4. Linear knowledge (G)
  
  5. Unmodeled knowledge (C)
  
  6. Skill score (SS)
  
  7. Regression bias (RB)
  
  8. Base rate bias (BRB)
  

• Firefox: Firefox browsers may add an .html extension that must be deleted after download. The most recent update to Firefox solved a default file usability problem. Files downloaded in earlier versions may not be usable even after removing the extra extension.
  
  
• Safari: A "bad server response" error on some combinations of Safari versions and Mac operating system versions may be fixed by setting an operating system configuration specific to the browser, however, should you encounter this error, it may be faster to use a different browser.
  
  If the Safari browser adds an extra extension to the filename, you can remove the extra .html extension before the download.
  
  
• Internet Explorer browsers vary in their treatment of the downloaded file.

Resources