Disagreement between studentized Breusch-Pagan test and the plots "residuals vs fitted" and "scale location" Given the model:
> Durée <- c(6,5,3.5,3,5,3,2,8, 2.5) 
> Note <- c(18,16,14,10,15,13,8,19,12) 
> model <- lm(Note ~ Durée)

I was tasked, among other things, to verify whether homoscedasticity is true.
After running  plot(model) I was able to visualise the following graphs:



From the Residuals vs Fitted and Scale-Location plots, we can see that the line is very far from being straight, which indicates the presence of heteroscedasticity.
However, when I run the studentized Breusch-Pagan test using the command bptest(model), I got the following output:
    studentized Breusch-Pagan test

data:  model
BP = 1.8622, df = 1, p-value = 0.1724

The test gives a p-value of 0.1724, which is greater than 0.05. This means that we can't reject the hypothesis of homoscedasticity, which contradicts, at least in my understanding, the output of the plots previously mentioned.

You just don't have enough data to see whether homoscedasticity is violated with only 9 data points. Maybe you could include a hint that homoscedasticity might be violated but you just don't have enough information to tell.
