Chapter 3: Descriptive Measures

Explain what each of symbol represents:

$a)\sum _{}b)nc)\stackrel{-}{x}$

Explain why minimum and maximum observations are added to the three quartiles to describe better the variation in a data set.

Is an extreme observation necessary an outlier? Explain your answer.

State pertinent properties of boxplots for symmetric, left-skewed and right-skewed distributions.

Regarding the interquartile range,

(a) What type of descriptive nature is it?

(b) What does it measure?

Identify a use of lower and upper limits.

When are the adjacent values just the minimum and maximum observation?

Which measure of variation is preferred when

(a) the mean is used as a measure of center?

(b) the median is used as a measure of center?

Fill in the blanks: Roughly, when arranged in increasing order, the middle $50\%$of a data set are found between _______ and _______ .

Fill in the blanks: Roughly, when arranged in increasing order, the uppermost $25\%$of the dataset are greater than or equal to _______ .