Statistics Task

Question

A regression equation was computed to be y = 5 + 3x.

1. What is the purpose of a regression equation?
2. what does the 3 represent in this model ?
3. what does the 5 represent in this model?
4. if the model represents the relationship between the number of sales on duty, how can this model be interpreted?

Answer 1

So the regression equation is how much the value of x regresses or decays over time. First I would re-write this equation as y = 3x + 5. The three in question is the slope at which the sales regress here. That slope is 3/1. The five is the y-intercept, or where the line/linear function crosses the y-axis. What you will do next is to draw a t-table, and plug in values for x, the input.

when we do this we get the following ordered pairs: (0, 5), (1, 8), (2, 11) and if we plug in negative values for x we get (-1, 2) , (-2, -1) and (-3, -4). We can plot these lines on a sheet of graph paper. As you get more comfortable graphing linear equations, you will see that for every next point, you go up three spaces, then over to the right one space. For the bigger purpose of the equation, we see that if we have no sales, then we make $5.00. When we have 1 sale, we earn $8.00. For every sale we get three more dollars. I hope this helps!

Answer 2

A regression equation which line best fits the data. A linear plot (i.e. a straight line) usually is the simplest way to present data. The "3' represents the slope of the regression equation, the "5" is the y-intercept. If "y" is the amount of money taken in, then the amount of money taken in is three times the number of sales(x).