Class: Rsquared::PropTest

Inherits:
StatTest show all
Defined in:
lib/Rsquared/PropTest.rb

Instance Attribute Summary

Attributes inherited from StatTest

#pvalue

Instance Method Summary collapse

Methods inherited from StatTest

#inspect, #setSidedness!, #significant?

Constructor Details

#initialize(data, p0, sided) ⇒ PropTest

Returns a new instance of PropTest.



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# File 'lib/Rsquared/PropTest.rb', line 4

def initialize(data, p0, sided)
 	 @data = data
		 @p0 = p0
		 @sided = sided

		 if (@data.length*@p0 < 10.0) or (@data.length*(1.0-@p0) < 10.0) then
 raise AssumptionError, "The number of successes or failures prediced by the proportion is too small"
		 end
		 
		 @stderr = Math.sqrt((@p0*(1.0-@p0))/@data.length)
		 @pstat = ((@data.sum.to_f/@data.length.to_f) - @p0)/@stderr
		 @pvalue = Distribution::Normal::cdf(@pstat)
		 self.setSidedness!(@sided)
end

Instance Method Details

#statistic ⇒ Object

Returns the z-statistic



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# File 'lib/Rsquared/PropTest.rb', line 23

def statistic
	    	@pstat
end