# Write an algorithm for k-nearest neighbor classification of drugs

The study of mathematical logic led directly to Alan Turing 's theory of computationwhich suggested that a machine, by shuffling symbols as simple as "0" and "1", could simulate any conceivable act of mathematical deduction. This insight, that digital computers can simulate any process of formal reasoning, is known as the Church—Turing thesis. Herbert Simon predicted, "machines will be capable, within twenty years, of doing any work a man can do". Marvin Minsky agreed, writing, "within a generation The data can also be found on Kaggle. We will require the training and test data sets along with the randomForest package in R. Let us get started. Scribbles on Paper Hand writing is unique to each person, and specifically the numbers we write have unique characteristics mine are difficult to read.

Yet when we read numbers written by other people, we can very quickly decipher which symbols are what digits. Since there is increasing demand to automate reading handwritten text, such as ATMs and checks, computers must be able to recognize digits.

So how can we accurately and consistently predict numbers from hand written digits? The data set itself consists of training and test data describing grey-scale images sized 28 by 28 pixels. The columns are the pixel number, ranging from pixel 0 to pixel total pixelswhich have elements taking values from 0 to The training set has an additional labels column denoting the actual number the image represents, so this what we desire from the output vector from the test set.

## Classification Concept

As we can see, the image numbers are in no particular order. The first row is for the number 1, the second for 0, and third for 1 again, and fourth for 4, etc.

The first 10 digits represented by the first 10 rows of written numbers from the training data are shown below. Since the values range from 0 towe had to normalize them from 0 to 1 by dividing them by And it will give us this: The below code stacks the rows 1 to 5 on top of the rows 6 through Creating a Stacked PNG for 10 Digits And the image resulting from the above code we saw already, as the first series of handwritten numbers above.

Random Forests Now that we know how the image was mapped onto the data set, we can use random forests to train and predict the digits in the test set.

With the randomForest package loaded, we can create the random forest: Creating RandomForest After taking out the labels in the training set, we can use train. We will use 1, trees bootstrap sampling to train our random forest. Note that the creation of this random forest will take some time- over an hour on most computers.

I left R running overnight to ensure that it would be completed by morning. RandomForest Above, we have the default output of the random forest, containing the out-of-bag error rate 3.

We see large numbers down the diagonal, but we should not stop there. Then we can call plot on rf. The error from the classification using that particular tree is the OOB error.

Next we can observe which variables were most important in classifying the correct labels by using the varImpPlot function. Important Pixels We can see the most important pixels from the top down-,etc. There is another step where we can rerun the random forest using the most important variables only.

Predicting Digits Lastly, we need to predict the digits of the test set from our random forest. As always, we use the predict function. However, since we already specified the test data in our randomForest function, all we need to do is call the proper elements in the object. The first 15 are down below: We did relatively well at 0.

Kaggle Submission And there we have it, folks! We used random forests to create a classifier for handwritten digits represented by grey-scale values in a pixel matrix.

And we successfully were able to classify Stay tuned for predicting more complex images in later posts!Applications of Machine Learning in Pharma and Medicine 1 – Disease Identification/Diagnosis The k-nearest neighbor algorithm assigns class based on the values of the most similar training examples.

the organization HealthMap uses automated classification and visualization to help monitor and provides alerts for .

## Classification Algorithms

Preprocessing is one of the main components in a conventional document categorization (DC) framework. This paper aims to highlight the effect of preprocessing tasks on the efficiency of the Arabic DC system.

In this study, three classification techniques are used, namely, naive Bayes (NB), k-nearest neighbor (KNN), and support vector machine .

They test the supervised approach with several algorithms (Naive Bayes, Decision Trees, K-Nearest Neighbor and SVM) and the results are comparable to previous results in the subjectivity domain, with SVM algorithm achieving the best result. Since December, bitcoins can not only be traded at more or less dubious exchanges, but also as futures at the CME and CBOE. And already several trading systems popped up . Jan 16,  · R: Classifying Handwritten Digits (MNIST) using Random Forests Hello Readers, The last time we used random forests was to predict iris species from their various characteristics.

Learn the key difference between classification and clustering with real world examples and list of classification and clustering algorithms. Dataaspirant A Data Science Portal For Beginners.

k-nearest neighbor; Decision trees Random forests; vector machine classifier is one of the most popular machine learning classification algorithm. A very common supervised machine learning algorithm for multiclass classification is k-Nearest Neighbor. This is an instance-based machine learning algorithm, or what's also called lazy learning. Artificial intelligence (AI), k-nearest neighbor algorithm, kernel methods such as the support vector machine (SVM), that a mathematical formula developed with the help of AI correctly determined the accurate dose of immunosuppressant drugs to give to .

A3: Accurate, Adaptable, and Accessible Error Metrics for Predictive Models: abbyyR: Access to Abbyy Optical Character Recognition (OCR) API: abc: Tools for.

Valence Analytics: R: Classifying Handwritten Digits (MNIST) using Random Forests