Presentation on theme: "Prior Knowledge Linear and non linear relationships x and y coordinates Linear graphs are straight line graphs Non-linear graphs do not have a straight."— Presentation transcript:
Prior Knowledge Linear and non linear relationships x and y coordinates Linear graphs are straight line graphs Non-linear graphs do not have a straight lines
Linear functions and data Scatter plot- a graph or diagram using coordinates to display data for two variables, usually to look for a trend Consists of an X axis (the horizontal axis), a Y axis (the vertical axis), and a series of dots. Dots represents one observation from a data set. Scatter plots are used to analyze patterns in bivariate data. By looking at a scatter diagram, we can see whether there is any connection (correlation) between the two sets of data.
Regression line (line of best fit) on Scatter plots A straight line that describes how a response variable y changes as an variable x changes Regression lines are often used to predict the value of y for a given value of x.
Correlation If there is a correlation between two sets of data, it means they are connected in some way. Less scatter around the best-fit line, the stronger the relationship is between the two quantities. If the points are close to the best-fit line = strong correlation. If the points are loosely scattered = weak correlation. Zero correlation = no linear relationship between the variables- if a line of best fit can not be drawn Positive correlation= best fit line slopes upwards, line slopes down Negative Correlation= the dependent variable decreases as the independent variable increases.