Usage

[accL, precL, accP, precP, querr] = localizationerror(m)
[res, meta, par] = localizationerror(m,errorflag)

Input parameters

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

accabsP mean absolute polar 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