STAT FINAL
A description of different houses on the market includes the following three variables. Which of these variables is quantitative? 1. The square footage of the house 2. The monthly gas bill 3. The monthly electric bill 4. All of the above
4. All of the above
Researchers are conducting a state-wide survey for the U.S. Postal Service. The survey records many different variables of interest. Which of the following variables is categorical? 1. The number of people, both adults and children, living in the household 2. The total household income, before taxes, in 2010 3. The age of the respondent 4. The county of residence
4. The country of residence
The five‐number summary of a set of data A) is the mean, standard deviation, first quartile, median, and third quartile. B) is the mean, median, mode, variance, and standard deviation. C) can be computed from the information in a stemplot. D) is the minimum, the interquartile range, the mean, the median, and the maximum.
C) can be computed from the information in a stemplot.
The standard deviation s is a useful measure of a characteristic of a distribution of data values. Which of the following statements about s is FALSE? A) The standard deviation measures the spread of the data around the mean. B) The standard deviation is appropriate as a measure of spread when the mean is chosen as the measure of center. C) The standard deviation can never be negative. D) As the data values become more spread out about their mean, s becomes larger. E) The standard deviation is resistant; in other words, outliers do not affect it.
E) The standard deviation is resistant; in other words, outliers do not affect it.
Categorical variables place cases into____ groups
Many
We have a data set where the cases are college students. One of the variables in the data set is "age of the student." What type of variable is age of the student?
Quantitative
Variable
Special characteristic of a case EX: if she was taking weight from the class, the people would be cases, the weight would be the variable.
A zip code/ phone number
Would still be categorical
cases
are the objects described by a set of data. Cases may be customers, companies, experimental subjects
A variable is a characteristic of a
case
A type of variable where arithmetic operations do not make sense are called
categorical
We have a data set where the cases are college students. One of the variables in the data set is "gender." The values of gender are 1 if the student is male and 2 if the student is female. What type of variable is gender?
categorical
Density Curve
describes shape of the histogram. Can not be below horizontal axis.
Explanatory variable
explains or causes changes in the response variable; Response variables happen last
Label
is a special variable used in some data sets to distinguish between cases
Response variable
measures an outcome of a study
Categorical
no # to measure; Pie chart or Bar graph
Quantitative
numerical value; Histogram or stem plot
Distribution
of a variable tells us the values that a variable takes and how often it takes each value
Unimodel
one peak in graph
On a stem and leaf, the #'s are right skewed if...
the majority is on the lower end, least amount end
Statistics
the science of learning from data
Bimodel
two peaks in graph (symmetry)
Associated variables
two variables measured on the same cases
