Unit 1 Flashcards
The science and art of collecting, analyzing, and drawing conclusions from data
Statistics
An object described in a set of data. Individuals can be people, animals, or things
Individual
An attribute that can take different values for different individuals
Variable
Assigns labels that place each individual into a particular group, called a category
Categorical Variable
Takes number values that are quantities - counts or measurements
Quantitative Variable
A quantitative variable that takes a fixed set of possible values with gaps in between them
Discrete Variable
A quantitative variable that can take any value in an interval on the number line
Continuous Variable
Tells us what values a variable takes and how often it takes those values
Distribution
Shows the number of individuals having each value
Frequency Table
Shows the proportion or percent of individuals having each value
Relative Frequency Table
Shows each category as a bar. The heights of the bars show the category frequencies or relative frequencies
Bar Graph
Shows each category as a slice of the “pie.” The areas of the slices are proportional to the category or relative frequencies
Pie Chart
A table of counts that summarizes data on the relationship between two categorical variables for some groups of individuals
Two-Way Table
Gives the percent or proportion of individuals that have a specific value for one categorical variable
Marginal Relative Frequency
Gives the percent or proportion of individuals that have a specific value for one categorical variable and a specific value for another categorical variable
Joint Relative Frequency
Gives the percent or proportion of individuals that have a specific value for one categorical variable among individuals who share the same value of another categorical variable (the condition)
Conditional Relative Frequency
Displays the distribution of a categorical variable for each value of another categorical variable. The bars are grouped together based on the values of one of the categorical variables and placed side-by-side
Side-by-side Bar Graph
Displays the distribution of a categorical variable as segments of a rectangle, with the area of each segment proportional to the percent of individuals in the corresponding category
Segmented Bar Graph
A modified segmented bar graph in which the width of each rectangle is proportional to the number of individuals in the corresponding category
Mosaic Plot
Happens between two variables when knowing the value of one variable helps us predict the value of the other
Association
Shows each data value as a dot above its location on a number line
Dotplot
If the right side of the graph is approximately a mirror image to the left side
Symmetric
If the right side of the graph is much longer than the left side
Skewed to the Right
If the left side of the graph is much longer than the right side
Skewed to the Left
Shows each value separated into two parts: a stem, which consists of all but the final digit, and a leaf, the final digit. The stems are ordered from lowest to highest and arranged in a vertical column. The leaves are arranged in increasing order out from the appropriate stems
Stemplot
Shows each interval of values as a bar. The heights of the bars show the frequencies or relative frequencies of values in each interval
Histogram
A number that describes some characteristic of a sample
Statistic
A number that describes some characteristic of a population
Proportion
A statistical measure that isn’t sensitive to extreme values
Resistant
The midpoint of a distribution, the number such that about half the observations are smaller and about half are larger
Median
The distance between the minimum value and the maximum value
Range
Measures the typical distance of the values in a distribution from the mean
Standard Deviation
Average squared deviation
Variance
Divide the ordered data set into four groups having roughly the same number of values. To find the quartiles, arrange the data values from smallest to largest and find the median
Quartiles
The median of the data values that are to the left of the median in the ordered list
First Quartile
The median of the data values that are to the right of the median in the ordered list
Third Quartile
The distance between the first and third quartiles of a distribution
Interquartile Range
Consists of the minimum, the first quartile, the median, the third quartile, and the maximum
Five-number Summary
A visual representation of the five-number summary
Boxplot
