Bayes analysis for a linear trend.
I'm trying to figure out the best way to test for a linear trend in a data-set I have.
the data consists of four variables, each represent an object size, and the dependent variables are reaction times for each object size.
My hypothesis is actually a null-hypothesis. I predict that reaction times will not increase as the object size increases (a linear trend). I could do a simple RM-ANOVA and test for a linear trend by using a comparison with linear weights (i.e. -3, -1, 1, 3) and see that the linear comparison is insignificant, but of course that is not a suitable way to support a null hypothesis, so a Bayesian analysis seems to me like a proper solution, by calculating the probability of receiving my data given that the null is correct.
Please advise me with a possible way to test for such a hypothesis using Bayes analysis in JASP, if there is one.