Significance test comparing slopes from linear fit

[iiwanovic]

I would like to compare four slopes I got from linear fits through five data points for each fit. The fitting results (for the slopes) are as follows:
1: 0.08885 ± 0.00991
2: 0.08744 ± 0.0118
3: 0.10288 ± 0.00669
4: 0.0926 ± 0.01285

My hypothesis is that they are all not significantly different from each other and I would like to put that into a number. Can I run an unpaired t-test putting N=5? I guess I should loose a degree of freedom due to the linear fit. Or are there other tests better suited for this problem? Thanks a lot for your help in advance.

 

[jvicens]

Thank you for your question. I would recommend using a one-way ANOVA (analysis of variance) test to compare the four slopes you obtained from your linear fits. This test is specifically designed to compare the means of more than two groups, which is the case in your situation.

Before running the ANOVA, you should first check the assumptions of the test, such as the normality and homogeneity of variances. If these assumptions are not met, you may need to consider using a non-parametric test instead. Additionally, since you have a small sample size (N=5), you may also want to consider using a post-hoc test, such as Tukey's HSD, to determine which specific pairs of slopes are significantly different from each other.

Overall, I believe that using a one-way ANOVA would be the most appropriate and robust approach for comparing the four slopes you obtained from your linear fits. I hope this helps and best of luck with your analysis.