Apologies for the awkward title, but I hope to be able to regain your confidence.
Let's start with the final output I got, so at least you can understand why I'm not happy/concerned about the outcome.
The graph shows the past 2 years website traffic. I was interested to understand whether my learnings could have been applicable to my main profession. I truly believe this is the case, but the results I got aren't very encouraging.
The plot has been obtained running the data past an ARIMA model after different normalisations occurred (e.g. differencing, log, etc.) The best ARIMA model was found to be 11, 1, 11. This is supported from the below:
You may be tempted to say P = 15, but in fact, after several computations, the best RSME was given by the above. See below (though I'm not sure that RSME can be really applied here)
I understand that almost 69% of confidence is far from being perfect, but I would have in some case expected to return something better than the above output.
Do you have any ideas of what I could have done wrong, what I may improve and how? Bear in mind I'm learning, so please excuse my limited understanding on complex terminology. The plainer you go, the best chance for me to understand.
Thanks for your support.
Thanks to all comments below, I made some progress. I was also able to get through the SARIMA and counter verify the data with the new data acquired since I started this learning project.
See below the new plot.
Although a perfectly matching fit with the "training" data, when it comes to the forecast, the data hardly correspond. Given my in-expertise, is the above plot something that you would deem normal? Or Do I need to re-work a lot more to get anything better?