# Maths 533

Topics: Skewness, Normal distribution, Median Pages: 3 (899 words) Published: April 11, 2013
Brief Introduction
AJ Davis is one of the department stores which have many credit customers. The store has decided to find out more information about its credit customers. There are 50 credit customers who were selected for the data collection on five variables such as location, income, size, years, and credit balance. In order to understand more about their customer, AJ DAVIS must used graphical, numerical summary to be able to interpret and better expand their business in the future.

A. Discuss your 1st individual variable, using graphical, numerical summary and interpretation:
A histogram shows the distribution of data within the income generated from 20-60. In this Histogram graph of Income, it shows that the graph is not symmetrical. The graph shows that this graph is more like two graph because there is a clear difference between income generating from 20-40 and from 50-above. There are two separated cluster; therefore, the skewness of this graph is skewed right. Income has a lower value of kurtosis which indicates a lower, less distinct peak. The following table shows the numerical summary of Income:

B. Discuss your 2nd individual variable, using graphical, numerical summary and interpretation :

A histogram shows the distribution of data within the Credit Balance. In this Histogram graph of Credit Balance, it shows that the graph is symmetrical with the exception of one outlier which is credit balance of \$2,000. This is a normal distribution with a single peak at the center of the distribution. By symmetric, I mean that the distribution can be folded about an axis and the two sides almost coincide. The following table shows the numerical summary of Credit Balance:

The P-value of the Credit Balance using the Anderson-Darling Normality Test is 0.400 and the A-Squared is 0.38. With the 95% Confidence Interval for Mean, Median, and St Dev are as followed:

This graph show that the number of the customers current credit card...