Summer stats Flashcards
Statistics
The science and art of collecting, analyzing, and drawing conclusions from data.
Individuals
An object describe in a set of data. Can be people, animals, or things
Variable
An attribute that can take different values for different individuals
Categorical Variable
Assigns labels that place each individual into a particular group, called a category
Quantitative Variable
Takes number values that are quantities-counts or measurements
Discrete Variable
A quantitive variable that takes a fixed set of possible values with gaps between them
Continuous Variable
A quantitative variable that can take any value in an interval on the number line
Frequency Table
Shows the number or count of individuals having each value.
Relative Frequency Table
Shows the proportions or percent of individuals having each value.
Bar graph
Shows each category as a bar. The heights of the bars show the category frequencies or relative frequencies. There is space between the bars.
Pie Chart
Shows each category as a slice of the pie. The areas of the slice are proportional to the category frequencies or relative frequencies
Association
There is an association between two variables if knowing the value of one variable helps us predict the value of the other. If knowing the value of one variable does not help us predict the value of the other, then there is no association between the variables.
Symmetric Distribution
A distribution is roughly symmetric if the right side of the graph (containing half of the observations with the largest values) is approximately a mirror image of the left side.
Skewed Distribution
A distribution is skewed tot he left if the left side of the graph is much longer than the right side. In other words distribution is skewed left if there is a tail stretching out of the left side. a distribution is skewed to the right if the right side of the graph is much longer than the left side.
Mean
The mean of a disribition of quantitative data is the average of the individual data values. To find add all the values and divide by the total number of data values
Statistic
A number that describes some characteristic of a sample
Parameter
A number that describes some characteristic of a population
Resistant
A statistical measure is ____ if it isn’t sensitive to extreme values(outliers)
Median
The midpoint of a distribution is the number such that about half the observations are smaller and about half is larger. to find arange the data values from smallest to largest. If the number of data values is odd the ____ is the middle value. If the number of data is even, then it’s the average of the two middle values. The _____ Repersentst he 2nd Quartile andis at 50%
Range
The ___ of a distribution I the distance between the minimum value and the maximum value. Max-Min= ___