Scatterplots and Trend Lines
ordered pair
(x,y)
scatterplot
A graphed cluster of dots, each of which represents the values of two variables
trend line
A line on a scatterplot that helps show the correlation between data sets more clearly. It is used to make predictions. It is also called a line of best fit.
association
A measure of the relationship between two variables
outlier
A value that "lies outside" (is much smaller or larger than) most of the other values in a set of data.
negative correlation (definition & graph)
Data points that go generally downward from left to right
positive correlation (definition & graph)
Data points that go generally upward from left to right
y = -1/3x + 8
What is the trend line?
y = -10/3x + 80
What is the trend line?
y = -25/3x + 200
What is the trend line?
y = -25x + 250
What is the trend line?
y = -50/3x + 400
What is the trend line?
y = -50x + 500
What is the trend line?
y = -x + 10
What is the trend line?
y = 1/2x + 3
What is the trend line?
y = 10x
What is the trend line?
y = 25/2x + 75
What is the trend line?
y = 25x + 150
What is the trend line?
y = 50x
What is the trend line?
y= -10x + 100
What is the trend line?
y= 25x
What is the trend line?
y= 5x+30
What is the trend line?
y=x
What is the trend line?
line of best fit
a line drawn in a scatter plot to fit most of the dots and shows the relationship between the two sets of data. It is used to make predictions. It is also called a trend line.
prediction
a logical guess of one variable when given information about the other variable.
dependent variable
a variable whose value depends on the independent variable. the y.
independent variable
a variable whose values are independent of changes in the values of other variables. the x. The value we can choose.
correlation
another term for "association"
clustering
data values occurring close together
no correlation (definition & graph)
there is no relationship between two variables (like your height and the month you were born)
