Lines of best fit (1 Viewer)

[tlv6554]

Can someone please explain when to do a curve and when to do a straight line?

 

[kawaiipotato]

I think it'd usually be specified. It also helps to understand what the data is explaining/coming from (say you knew the underlying formula for it, you could see what the theoretical curve should be).

 

[jazz519]

It all depends on the data. If you have an equation this can be easier because say example the equation is for concentration, c=n/v, where we are keeping n constant and changing v, resulting in a change in c. You can see that c is inversely proportional to v and this resembles a y=1/x hyperbola type of graph (a curve), while in a different equation that might be a line graph.

If the data is just random like from an experiment, then to decide between a line of best fit and a curve of best fit, just use common sense. If the relationship between the two axis looks curved it is probably a curve of best fit, likewise for line of best it, as I doubt the HSC examiners are going to make it vague as to what the relationship looks like