Within memory_experimentSP/models.py Constants class (actual values are just examples here):
-----------------------
Payment for More or Less Page:
	# Set bonus and loss for answering whether more or less positive/negative facts (in $) 
	more_or_less_bonus = 0.5
	more_or_less_loss = 0
------------------------
Payment for Counting Positive and Negative Facts Page:
	# Set bonus and penalty for answering how many good and bad facts (in $)
	score_bonus = 0.3
	score_penalty = 0.2
------------------------
Payment for Bayes Page:
	# Set bonus and loss for bayesian recall (in $)
	business_prospect_bonus = 0.1
	business_prospect_loss = 0
------------------------
Payment for Button Page:
	# Set these for detailed fact button bonus and loss (in $)
	# If the button pressed is a true positive recollection-
	recall_bonus = 0.3
	# If the button pressed is a false positive recollection-
	recall_penalty = 0.2
------------------------
Expected Payment:
	# Set these for the expected payments (in $) that are displayed on the welcome page
	lower_exp_payment = 3
	upper_exp_payment = 6
------------------------
You can adjust the default base participation in the session_config dictionary within the root settings.py- the relevant key is 'participation_fee'. The session specific base participation fee can be set at session configuration for mturk via oTree's interface.