Probability Units: Mean, Mode, Median, Variance, SD?

AI Thread Summary
Probability values are unitless, meaning they are expressed as numerical values without specific units. However, the mean, mode, and median of a dataset do have units, specifically in terms of the items being measured, such as apples. Variance is expressed in squared units, like apples squared, while standard deviation returns to the original unit, apples. This distinction is important for accurately interpreting statistical measures in probability scenarios. Understanding these units helps clarify the application of statistical concepts in real-world contexts.
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hihi
for example, I am doing a question involving the probability of the number of apples i eat in a day.

i need to find the mean, mode, median, variance and standard deviation.

do these values need to be in units of apples? or just like a numerical value such as 2.3 ?

thanks
 
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In the standard way of definining it, probability values are unitless. Say you had 2 green apples and 1 red apple. The probability of you picking a red apple is (1 apple)/(3 apples)=1/3. Essentially, the units of "apple" cancel, leaving only a number.

However, the mean, mode, median, variance, and standard deviation all have units. The first three are essentially ways of averaging, and so must have units of apples. The variance has units of apples^2, and the standard deviation has units of apples.
 
wow i never wuda thought maybe the other things but not variance being apple squared thanks
 

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