[accL, precL, accP, precP, querr] = localizationerror(m) [res, meta, par] = localizationerror(m,errorflag)
m | item list from a localization experiment. Columns:
|
localizationerror(m,errorflag) returns psychoacoustic performance parameters for experimental response patterns. m is a matrix. In each row of m, the information about the target and response in the columns must be provided.
[res, meta, par] = localizationerror(m,errorflag) calculates error metric res given by the string errorflag. meta contains additional metadata, par contains additional calculation results.
The errorflag may be one of:
accL accuracy (average) in the lateral dimension
precL precision (std. dev.) in the lateral dimension
- precLcentral precL derived from responses close to horizontal
- meridian (+-30 deg elevation)
accP accuracy (average) in the polar dimension
precP precision (circular std. dev.) in the polar dimension
- querr percentage of weighted polar errors > 45deg:
- [querr number_of_corrects total_number] = CalcAccPrec...
accE accuracy in the elevation
absaccE absolute accuracy in the elevation
absaccL absolute lateral accuracy
accabsL mean absolute lateral error
accPnoquerr accP with quadrant errors removed
precE precision in the elevation
querr90 precentage of weighted polar errors > 90deg
- precPmedian unweighted polar precision error considering targets around
- the median plane only (+/-30deg lateral)
- precPmedianlocal basing on precPmedian, quadrant errors (polar error >90 deg)
- are excluded. Similar to RMS local polar error (Middlebrooks, 1999)
precPnoquerr precP with quadrant errors removed
rmsL lateral RMS error according to Middlebrooks (1999)
- rmsPmedianlocal unweighted polar RMS considering targets around
- the median plane only (+/-30deg lateral) and excluding quadrant errors (polar error > 90deg). Identical to RMS local polar error in Middlebrooks (1999).
- rmsPmedian unweighted polar RMS considering targets around the median plane
- only (+/-30deg lateral). Includes quadrant errors.
- querrMiddlebrooks quadrant errors as in Middlebrooks (1999). Use
- central positions within +/-30deg, querr is when polar error is >90deg [querr number_of_corrects total_number] = CalcAccPrec...
corrcoefL lateral correlation coeffficient. Output parameter: [cc, p]
- corrcoefP polar correlation coeffficient, Only data within lateral
- +/-30deg are considered. Output parameter: [corr_coeff, p_of_significant_corr]
- SCC spherical/spatial correlation coefficient
- (Carlile et al., 1997)
- gainLstats performs linear regression to obtain lateral gain.
- See help of regress for a detailed description of the structure fields.
gainL lateral gain only
- pVeridicalL Proportion of quasi-verdical responses in lateral
- dimension
- precLregress lateral scatter around linear regression line
- (only quasi-veridical responses included).
- sirpMacpherson2000 performs an ad-hoc selective, iterative
- regression procedure (SIRP) in order to exclude outliers and reversals and isolate the main concentration of responses in the computation of the linear fits. Outlier distance criterion: 40deg. Parameters [f,r] correspond to regression results for frontal and rear hemisphere, respectively - see help of regress for a detailed description of the structure fields.
gainPfront frontal polar gain only
gainPrear rear polar gain only
gainP polar gain averaged between front and back
slopePfront slope in degrees of regression line (frontal only)
slopePrear slope in degrees of regression line (rear only)
slopeP slope in degrees of regression line (front and back)
- pVeridicalPfront Proportion of quasi-verdical polar responses in
- the front
- pVeridicalPrear Proportion of quasi-verdical polar responses in
- the back
- pVeridicalP Proportion of quasi-verdical polar responses in
- total
- precPregressFront polar scatter around linear regression line for
- the front (only quasi-veridical responses included)
precPregressRear same as precPregressFront but for the back
precPregress average between precPregressFront and precPregressRear
- perMacpherson2003 polar error rate used in Macpherson & Middlebrooks
- (2003). They measured the deviation of responses from the linear predictors obtained by an ad-hoc SIRP. Polar errors are defined by showing a deviation of >45deg (i.e., not being quasi-veridical) with respect to the linear flat stimulus prediction. Note that for this analysis the results from sirpMacpherson2000 are required and handled as localizationerror(m,f,r,'perMacpherson2003')
If no errorflag is provided, the function returns: accL, precL, precP, and querr