The huge amount of data that we’re generating each day , has led to an increase of the need for advanced Machine Learning Algorithms.
It is quite essential to know Machine Learning basics. Here’s a fast introductory section on what’s Machine Learning and its types.
Machine learning could also be a subset of AI that provides machines the power to hunt out out automatically and improve from their gained experience without being explicitly programmed.
There are mainly three kinds of Machine Learning discussed briefly below:
Supervised Learning: it’s that a neighborhood of Machine Learning during which the data provided for teaching or training the machine is well labeled then it becomes easy to work with it.
Unsupervised Learning: it is the training of knowledge employing a machine that’s unlabelled and allowing the algorithm to act thereon information without guidance.
Reinforcement Learning: it’s that a neighborhood of Machine Learning where an agent is put in an environment and he learns to behave by performing certain actions and observing the numerous possible outcomes which it gets from those actions.
Now, moving to our main blog topic,
What is KNN Algorithm?
KNN which stands for K Nearest Neighbor could also be a Supervised Machine Learning algorithm that classifies a replacement datum into the target class, counting on the features of its neighboring data points.
Let’s decide to understand the KNN algorithm with an essay example. Let’s say we might sort of a machine to differentiate between the sentiment of tweets posted by various users. to undertake to to the present we must input a dataset of users’ sentiment(comments). And now, we’ve to teach our model to detect the emotions supported certain features. as an example , features like labeled tweet sentiment i.e., as positive or negative tweets accordingly. For positive tweet, it’s labeled as 1 and for negative, it,’s labeled as 0.
Features of KNN algorithm:
KNN could also be a supervised learning algorithm, supported feature similarity.
Unlike most algorithms, KNN could also be a non-parametric model which suggests it doesn’t make any assumptions about the data set. which makes the algorithm not only simpler but also effective because now it can handle realistic data.
KNN is taken under consideration to be a lazy algorithm, i.e., it suggests that it memorizes the training data set rather than learning a discriminative function from the training data.
KNN is typically used for solving both classification and regression problems.
Disadvantages of KNN algorithm:
After multiple implementations, it has been observed that KNN algorithm doesn’t work with good accuracy on taking large datasets because the worth of calculating the space between the new point and each existing points is large , and successively it degrades the performance of the algorithm.
Disadvantages of KNN algorithm:
It has also been noticed that performing on high dimensional data is quite difficult with this algorithm because the calculation of the space in each dimension isn’t correct.
It is quite needful to perform feature scaling i.e., standardization and normalization before actually implementing KNN algorithm to any dataset. Eliminating these steps may cause wrong predictions by KNN algorithm.
Sensitive to noisy data, missing values and outliers: KNN is sensitive to noise within the dataset. we’d wish to manually impute missing values and deduct outliers.