When designing a new fMRI study, it is good practice to estimate the efficiency of your design to ensure that you will be able to accurately capture differences in brain activation as a function of your experimental design. There are several open source resources for doing so, but they are not flexible and will only work on the most simple designs. Neal has therefore created customizable scripts that allow for you to estimate efficiency for any design matrix. These scripts are located in the the "efficiency" repository and execute two basic steps:

(1) generation of a design matrix that codes for presentation of individual stimuli of EVs of interest (2) generation of efficiency estimation for individual stimuli, EVs, or contrasts of interests

When looking through the scrips, be sure to select the scripts that are best suited for your eventual analytical needs. For example, if you're primarily interested in looking at univariate contrasts, then you will likely use a script that calculates efficiency for specified contrasts. If you're instead interested in looking at representational change for individual stimuli, then you will likely use a script that calculates efficiency for individual stimuli. You may also be interested in calculating average efficiency across all of your EVs. It is a good idea to estimate efficiency for all of the above if you are planning on taking a multi-faceted analytical approach, and to then use your results to settle on the best approach based on your analytical priorities.