This section of the study reanalysed binocular summation data reported in a study by Baker, Lygo, Meese & Georgeson (2018), available at: http://dx.doi.org/10.1037/bul0000163 The raw data are available in the file [pmfdata.RData][1]. This file contains three variables: - *contrastsdB*: contains target contrast values in dB units - *alltrials*: a 3D matrix with dimensions [participant, condition, contrast]. Each value records the number of trials conducted for an individual participant in a particular condition at a given contrast. The contrasts map onto the values in contrastsdB. The conditions are: 1. left eye (right eye views mean luminance) 2. right eye (left eye views mean luminance) 3. binocular 4. binocular - *allcorrect*: a 3D matrix with the same structure as *alltrials*, but this time recording the number of trials that were correct in each condition The data were analysed using the script [powercontoursbinsumpar.R][2], which also generates [Figure 4][3]. Paths in the script will need to be updated to reflect local directory structures. [1]: https://osf.io/xfczr/ [2]: https://osf.io/c7hrn/ [3]: https://osf.io/3pfyj/