question: public ParameterGuesser ( Collection < WeightedObservedPoint > observations ) { MathUtils . checkNotNull ( observations ) ; if ( observations . size ( ) < 3 ) { throw new MathIllegalArgumentException ( LocalizedCoreFormats . NUMBER_TOO_SMALL , observations . size ( ) , 3 ) ; } final List < WeightedObservedPoint > sorted = sortObservations ( observations ) ; final double [ ] params = basicGuess ( sorted . toArray ( new WeightedObservedPoint [ 0 ] ) ) ; norm = params [ 0 ] ; mean = params [ 1 ] ; sigma = params [ 2 ] ; }
target:  Constructs instance with the specified observed points.