Data mining
Problem Definition
Market Analysis
Customer Profiling, Identifying Customer Requirements, Cross Market Analysis, Target Marketing, Determining Customer purchasing pattern
Corporate Analysis and Risk Management
Finance Planning and Asset Evaluation, Resource Planning, Competition
Fraud Detection
Customer Retention
Production Control
Science Exploration
> Data Preparation
Data preparation is about constructing a dataset from one or more data sources to be used for exploration and modeling. It is a solid practice to start with an initial dataset to get familiar with the data, to discover first insights into the data and have a good understanding of any possible data quality issues. The Datasets you are provided in these projects were obtained from kaggle.com.
Variable selection and description
Numerical – Ratio, Interval
Categorical – Ordinal, Nominal
Simplifying variables: From continuous to discrete
Formatting the data
Basic data integrity checks: missing data, outliers
> Data Exploration
Data Exploration is about describing the data by means of statistical and visualization techniques.
· Data Visualization:
· Univariate analysis explores variables (attributes) one by one. Variables could be either categorical or numerical.
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Univariate Analysis - Categorical |
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Statistics |
Visualization |
Description |
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Count |
Bar Chart |
The number of values of the specified variable. |
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Count% |
Pie Chart |
The percentage of values of the specified variable |
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Univariate Analysis - Numerical |
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Statistics |
Visualization |
Equation |
Description |
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Count |
Histogram |
N |
The number of values (observations) of the variable. |
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Minimum |
Box Plot |
Min |
The smallest value of the variable. |
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Maximum |
Box Plot |
Max |
The largest value of the variable. |
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Mean |
Box Plot |
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The sum of the values divided by the count. |
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Median |
Box Plot |
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The middle value. Below and above median lies an equal number of values. |
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Mode |
Histogram |
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The most frequent value. There can be more than one mode. |
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Quantile |
Box Plot |
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A set of 'cut points' that divide a set of data into groups containing equal numbers of values (Quartile, Quintile, Percentile, ...). |
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Range |
Box Plot |
Max-Min |
The difference between maximum and minimum. |
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Variance |
Histogram |
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A measure of data dispersion. |
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Standard Deviation |
Histogram |
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The square root of variance. |
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Coefficient of Deviation |
Histogram |
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A measure of data dispersion divided by mean. |
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Skewness |
Histogram |
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A measure of symmetry or asymmetry in the distribution of data. |
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Kurtosis |
Histogram |
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A measure of whether the data are peaked or flat relative to a normal distribution. |
Note: There are two types of numerical variables, interval and ratio. An interval variable has values whose differences are interpretable, but it does not have a true zero. A good example is temperature in Centigrade degrees. Data on an interval scale can be added and subtracted but cannot be meaningfully multiplied or divided. For example, we cannot say that one day is twice as hot as another day. In contrast, a ratio variable has values with a true zero and can be added, subtracted, multiplied or divided (e.g., weight).
· Bivariate analysis is the simultaneous analysis of two variables (attributes). It explores the concept of relationship between two variables, whether there exists an association and the strength of this association.
There are three types of bivariate analysis.
1.Numerical & Numerical
Scatter Plot, Linear Correlation …
2.Categorical & Categorical
Stacked Column Chart, Combination Chart, Chi-square Test
3.Numerical & Categorical
Line Chart with Error Bars, Combination Chart, Z-test and t-test
> Modeling
· Predictive modeling is the process by which a model is created to predict an outcome
· If the outcome is categorical it is called classification and if the outcome is numerical it is called regression.
· Descriptive modeling or clustering is the assignment of observations into clusters so that observations in the same cluster are similar.
· Finally, a ssociation rules can find interesting associations amongst observations.
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Classification algorithms: |
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1. Frequency Table · ZeroR , OneR , Naive Bayesian , Decision Tree 2. Covariance Matrix · Linear Discriminant Analysis , Logistic Regression 3. Similarity Functions 4. Others · Artificial Neural Network , Support Vector Machine Regression |
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1. Frequency Table 2. Covariance Matrix 3. Similarity Function 4. Others |
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Clustering algorithms are: |
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1. Hierarchical 2. Partitive |
> Evaluation
· helps to find the best model that represents our data and how well the chosen model will work in the future. Hold-Out and Cross-Validation
> Deployment
The concept of deployment in predictive data mining refers to the application of a model for prediction to new data.