# W2D3 -- DecisionMaking: Erratum

There are a few things in the tutorial notebook which have been flagged, but will unlikely be fixed before the tutorial. Putting them here for reference.

## Bugs:

(report potential bugs / errors here (ideally along with a solution))

Tutorial 1, section 1.1 equation (5) – mu_1 to be changed to mu_R

tutorial 2, equation 1.

sum should be over i, not over j

## Clarifications / Inconsistencies:

(report when something needs clarification (+suggest a clarification))

Tutorial 1, Exercise 2: It would be nice to have a definition of ‘accuracy’ somewhere, given that this needs to be calculated in the exercise.

Tutorial 1, Exercise 4 : Is there a reason why the average accuracy is represented wrt the decision speed while it was represented wrt to the decision time in exercise 2? I find it quite confusing. Moreover, I found that the way the decision speed is computed (as being the inverse

of decision time) makes it very hard to interpret.

Tutorial 3, exercise 1.

Defining state in the solutions is set to mu_0, on the equations it sampled from a multivariate gaussian N(mu_0,sigma_0). Consistent solution:

State = stats.multivariate_normal(mean=params[‘mu_0’],cov=params[‘sigma_0’]).rvs(1)

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