Distributions
The number equal to the area under a normally distributed density curve
What is 1?
This is calculated by taking the sum of all the values and dividing by the number of values.
What is the mean?
Type of variable that assigns individuals into a limited number of groups, sometimes based on a qualitative property
What is a categorical variable?
Graph that can be used to display the relationship/correlation between two quantitative variables
What is a scatterplot?
A regression line can use the given x value to predict this
What is the given y value?
The mean and median will be equal in this type of distribution
What is a normal distribution?
Group of summary statistics consisting of minimum, first quartile, median, third quartile, and the maximum
What is the five-number summary?
All groups on this kind of graph should be parts of a whole, and add up to 100%
What is a pie chart?
Statistic that describes a straight-line relationship of two quantitative variables as a number between -1 and 1
What is "r"?
The number that helps us predict a y value for a given x value, and it represents the amount y changes when x increases by one unit
What is the slope?
The rule of thumb we can use for normal distributions to find the percentage of observations that fall within 1, 2, or 3 standard deviations of the mean
What is the 68-95-99.7 rule?
The extreme values that will affect the mean of a set of data more than it affects the median
What are outliers?
This graph is used to display a quantitative variable change over time, and the scaling of the graph is very important to accurately display the data
This type of relationship will have a negative "r", as the two variables are inversely related
What is a negative relationship?
The statistical measure that describes how much variation in one variable is accounted for by the relationship with the other variable
what is r-squared?
These two measures of center and spread are more appropriate for a symmetrical distribution, rather than the five-number summary
What are mean and standard deviation?
The statistic that has the standard score of 0
What is the mean?
The type of graph to use when you want to be able to display distribution as well as maintain individual values with a small set of data
What is a stem-plot?
This variable, if present, is placed on the horizontal scale of the scatterplot
What is the explanatory variable?
This is referring to prediction outside the range of available data for a regression line, which should be avoided
What is extrapolation?
This kind of skewed distribution will drag the mean toward the right side, away from the median.
What is a right-skewed distribution?
This number represents the number of standard deviations that the observed value is above or below the mean
What is a standard score?
This graph can present similar data as a pie chart, but can be used if the data are not parts of a whole or if angles on a pie chart are too hard to compare
What is a bar graph?
Correlations are sensitive to these kinds of values, as they can greatly weaken an association between two variables
What are outliers?
The method used to find closest regression line where the sum of the squares of vertical distance from the data points to the line is the smallest
What is the least-squares method?