Regression line (Edexcel GCSE Statistics): Flashcards
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Practise the cards
10 cards from this deck
What is the formula for a regression line in statistics?
What is the formula for a regression line in statistics?
y = mx + c, where m is gradient and c is y-intercept.
How to plot a regression line from an equation?
How to plot a regression line from an equation?
Choose x-values, find y, plot points, draw line through.
What does the y-intercept tell us?
What does the y-intercept tell us?
Where line crosses y-axis; shows predicted y at x=0.
What is a limitation of the y-intercept?
What is a limitation of the y-intercept?
May not be realistic if outside data range.
How to interpret a gradient of 1.05?
How to interpret a gradient of 1.05?
Y increases by 1.05 for each 1 unit increase in X.
What does the gradient tell us about variable change?
What does the gradient tell us about variable change?
Rate at which y changes for a unit increase in x.
What is the key purpose of a regression line?
What is the key purpose of a regression line?
Understand relationship and make predictions.
Find two points for y=1.05x-3 using x=30 and x=80
Find two points for y=1.05x-3 using x=30 and x=80
(30,28.5) and (80,81)
Using gradient 1.05, find y change for x+5
Using gradient 1.05, find y change for x+5
y increases by 1.05×5 = 5.25
Find two points on y=1.05x-3 for x=20 and x=90
Find two points on y=1.05x-3 for x=20 and x=90
(20,18) and (90,91.5)