When using the naïve prediction, it is good for only a time series. Knowing how to compare and use data is important because there are hundreds upon hundreds of ways to analyze data and you have to be sure you are effectively analyzing the data.
Another aspect to look using naïve prediction is there could be seasonality in the market you are examining and this approach may not be the best to use. There are other factors to keep in mind such as drift and a shift in the average.
These are in depth formulas that can be manipulated and changed, but it is important to understand what goes into the equation because with that you can narrow in on the specific data that may be altering the results. There are many different resources to use on the Internet so be sure to fully understand what is happening before using this in your current setup. Join an investing group and see if other people are using this as you may find it is not widely used due to a various of reasons. Also, check out Macroaxis as there are many useful tools that can help expand your current trading setup.