CHAPTER 1 - SYSTEM OPERATIONLSM 880 Center Screen Area / Image Containers - Display and Image Analysis ZEISS10/2014 V_01 000000-2071-464 4756.11.2 Quantitative Colocalization Parameters Shown in the Data Table− No. of pixels in image ROI or scatter region− Area / relative area of image ROI or scatter region− Mean intensities / SD within image ROI or scatter region− Colocalization coefficients− Weighted colocalization coefficients− Overlap coefficient after Manders− Correlation coefficients (R and R2)6.11.3 Colocalization CoefficientstotalChcolocChpixelspixelsc,1,11 =totalChcolocChpixelspixelsc,2,22 =− Relative number of colocalizing pixels in channel 1 or 2, respectively, as compared to the totalnumber of pixels above threshold.− Value range 0 – 1 (0: no colocalization, 1: all pixels colocalize)− All pixels above background count irrespective of their intensity.Weighted colocalization coefficients∑∑=ii,totalii,colocChChM 111∑∑=ii,totalii,colocChChM 222− Sum of intensities of colocalizing pixels in channel 1 or 2, respectively, as compared to the overallsum of pixel intensities above threshold and in this channel.− Value range 0 – 1 (0: no colocalization, 1: all pixels colocalize)− Bright pixels contribute more than faint pixelsCorrelation coefficient, Pearson´s correlation coefficient∑ ∑∑−−−−=i iaveriaveriiaveriaveripChChChChChChChChR 22 )22(*)11()22(*)11(− Provides information on the intensity distribution within the colocalizing region− Value range -1 to +1-1,+1: all pixels are found on straight line in the scatter diagram0: pixels in scattergram distribute in a cloud with no preferential direction
