Page 61 - Reclaim YOUR DIGITAL GOLD (without audio)
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Data ColleCtion Harvesting



            the output using those values. As you may have guessed,
            it  performs  quite poorly. However, we can test  the
            accuracy of our model’s forecasts by comparing them to
            the expected results, and then we can change the values
            we use for W and b so that our model produces more
            accurate forecasts.

            This  procedure is  then  repeated.  One  round of weight
            and bias updates is referred to as a “training step.”

            Let’s take a closer look at what this means for our dataset
            in this specific scenario and context. At first glance, it
            appears that we’ve simply drawn a random line through
            the data. As the training progresses, it gets closer and
            closer to an optimal separation of wine and beer.



            EVALUATION PHASE


            After  the  training  phase  is  completed,  it  is  time  to
            evaluate the model to see if it is any good. The dataset
            that we previously set aside comes into play at this point
            in the process. The evaluation phase allows us to test
            our model using data that was not previously used for
            training. This statistic allows us to forecast how well the
            model will perform when applied to data that it has not
            yet been exposed to. This is meant to be an indication of
            how the model might perform in the real world.

            According to the commonly used rule of thumb, a good
            training-evaluation split should be in the 80/20 or 70/30
            range. The amount of the dataset that was initially used
            as the source determines a significant portion of this. If
            you have a large amount of data, a smaller percentage of
            it may be sufficient for the evaluation dataset.



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