statsmodels.sandbox.regression.try_ols_anova.form2design

statsmodels.sandbox.regression.try_ols_anova.form2design(ss, data)

convert string formula to data dictionary

ss : string

• I : add constant
• varname : for simple varnames data is used as is
• F:varname : create dummy variables for factor varname
• P:varname1*varname2 : create product dummy variables for varnames
• G:varname1*varname2 : create product between factor and continuous variable

data : dict or structured array

data set, access of variables by name as in dictionaries

Returns:

vars : dictionary

dictionary of variables with converted dummy variables

names : list

list of names, product (P:) and grouped continuous variables (G:) have name by joining individual names sorted according to input

Notes

with sorted dict, separate name list wouldn’t be necessary

Examples

>>> xx, n = form2design('I a F:b P:c*d G:c*f', testdata)
>>> xx.keys()
['a', 'b', 'const', 'cf', 'cd']
>>> n
['const', 'a', 'b', 'cd', 'cf']