The graph below includes the results of a linear regression using this data. (For example, the client identified with the triangle in the graph has a BMI of 30.36 and has cost the insurance company $62,592 over the previous 5 years.) Insurance Charges ($$) 70000 60000 50000 40000 30000 20000 10000 0 18 23 Males Smokers, aged 40 to 64 28 i BMI 33 Ta y = 1487x - 9399.7 R² = 0.6501 38 43 Interpret the value of the intercept of the regression line in the context of this question.

Definition Definition Measure of central tendency that is the average of a given data set. The mean value is evaluated as the quotient of the sum of all observations by the sample size. The mean, in contrast to a median, is affected by extreme values. Very large or very small values can distract the mean from the center of the data. Arithmetic mean: The most common type of mean is the arithmetic mean. It is evaluated using the formula: μ = 1 N ∑ i = 1 N x i Other types of means are the geometric mean, logarithmic mean, and harmonic mean. Geometric mean: The nth root of the product of n observations from a data set is defined as the geometric mean of the set: G = x 1 x 2 ... x n n Logarithmic mean: The difference of the natural logarithms of the two numbers, divided by the difference between the numbers is the logarithmic mean of the two numbers. The logarithmic mean is used particularly in heat transfer and mass transfer. ln x 2 − ln x 1 x 2 − x 1 Harmonic mean: The inverse of the arithmetic mean of the inverses of all the numbers in a data set is the harmonic mean of the data. 1 1 x 1 + 1 x 2 + ...