please corret me if i am incorrect in my understanding of a RV,PMF or anything else but as i understand it a random variable simply maps a expirmental outcome to a real number. And a probability mass function simply gives the probabilty that a number will occur.(adsbygoogle = window.adsbygoogle || []).push({});

Now my question is this: why cant we simply map a expiremental outcome to a probability rather than use a random variable to map from the sample space a to a real number then the map a real number to a probability via the PMF?

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# Why are random variables needed?

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