chapter 2-5 intro to data analytics
If a value represents the 95th percentile, this means that:
95% of all values are below this value
categorical
Gender and states of residence are examples of ____ data
A variable (or field or attribute) is a characteristic of members of a population, whereas an observation (or case or record) is a list of all variable values for a single member of a population.
True
Abby has been keeping track of what she spends to stream movies. The last seven week's expenditures, in dollars, were 6, 4, 8, 9, 6, 12, and 4. The mean amount Abby spends on streaming movies is $7.
True
Age, height, and weight are examples of numerical data.
True
The mean is a measure of central tendency.
True
The median of a data set with 30 values would be the average of the 15th and the 16th values when the data values are arranged in ascending order.
True
The value of the mean times the number of observations equals the sum of all of the data values.
True
The average score for a class of 30 students was 75. The 20 male students in the class averaged 70. The 10 female students in the class averaged:
higher than the males
The difference between the first and third quartile is called the:
interquartile range
The interquartile range (IQR) encompasses what percent of the observations?
middle 50%
The median can also be described as the:
middle observation when the data values are arranged in ascending order
As a measure of variability, what is defined as the maximum value minus the minimum value?
range
A variable is classified as ordinal if:
there is a natural ordering of categories