Summary statistics: The mean

One of the first things that you would like to know about a probability distribution are some summary statistics that capture the essence of the distribution. One example of such a summary statistics is the mean. The mean of a probability distribution is calculated by taking the weighted average of all possible values that a random variable can take. In the case of a discrete variable, you calculate the sum of each possible value times its probability. Let's go back to our probability mass function of the first exercise.

Calculate the expected value of the probability distribution and store this in the variable expected_score. expected_score should be a number rounded to 1 decimal. Note that you have a dataframe data available in your console that contains a vector of outcomes called outcome and a vector of probabilities called probs. This dataframe is the exact same as the table displayed above.
Print the variable expected_score

Take Hint (-30 XP)

Exercise

Summary statistics: The mean

Instructions