Mathematics and Statistics are quite far behind in my educational curriculum, and yet now I seem to need them again, so this set of questions is very basic I suppose:
What is a trend line? What various types of trend lines are there? And what are their respective use or relevance?
I'm working on a thesis and I am producing some visual rendering of a survey I ran, in which I tried to measure public knowledge of (colonial) history and heritage in a town of Kerala, India.
I have data for instance, representing the result of a test, the average result of which is compared to various criteria of the population (age, education, etc.) With regard to criteria such as age-group, income or education, it is also interesting to find out whether their increase improves the results.
I am working on this data with LibreOffice, which offers me the possibility to show a "trend line", and I suppose the trend-line is adequate to show the relation between x and y, i.e. criteria and result. However, there are 4 types of trend lines available: linear, logarithmic, exponential and power.
Which one should I chose? Which difference does it make? How would I figure out a trend line if LibreOffice would not do it for me?
Wikipedia brings some light on those questions. Although I am not sure whether I should look at linear regression or technical trend line analysis.
Could you please provide a short "Trend Line for Dummies" introduction? Thanks :)