Data Analytic and Business Intelligence Reports 2022

Data Analytics and Business Intelligence

Data Analytics and Business Intelligence
Statistics
Statistics refers to the science that deals with the application of mathematical methods in
the evaluation of data to derive information of interest (Barbara & Susan, 2014). Statistics is
generally divided into two types. The first type is descriptive statistics which is a form of
statistics that summarizes the attributes in a dataset (Douglas, William, & Samuel, 2012).
The second type is the inferential statistics which is a form of statistics that estimates the
properties of attributes in a dataset (Douglas, William, & Samuel, 2012).
Population is the group of elements whose characteristics are to be evaluated in a
statistical study (Everitt & Skrondal, 2010). The subset of a population used in the analysis in
descriptive and inferential statistics is called a sample. Variables are countable and measureable
attributes of a dataset. Variables are either quantitative or qualitative in nature; Quantitative
variables are variables that can be expressed using numerals or integers while variables that are
nonnumeric are qualitative variables (Creswell, 2014). The types of variables are dependent on
the measurement scales. There are four measurement scales; nominal, ordinal, interval and ratio
scales (Norman, 2010).
An example of descriptive statistics is the mean share price of Apple on the NASDAQ
while an example of inferential statistics is the relationship between price of iPhones and the
share price of Apple.
Frequency Table
Frequency tables are tabular representations of counts of entries of the categories or
classes of qualitative variables. Visually, the information in the frequency tables can be
represented using pie charts and bar charts. Frequency distributions are extensions of frequency
tables with the inclusion of either cumulative values of the frequencies or the relative values of
the frequencies (Howitt & Cramer, 2010). Visually, the information in the frequency
distributions can be represented using histograms and frequency polygons.
Consider the Apple’s products characteristics data with a sample of 200 products, the
example of a frequency table and a frequency distribution are as given in Table 1: Frequency
Table and Table 2: Frequency Distribution below.Table 1: Frequency Table
Product Frequency
AirPods 2 40
MacBook Pro 5
iPad Mini 5 8
iPhone 15
Mac Pro 30
iPad Pro 37
iPad 13
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Data Analytics and Business Intelligence
AirPower 6
Apple Watch Series 5 9
iPod Touch 17
Apple TV 20
Table 2: Frequency Distribution
Product Frequency Cumulative Frequency
AirPods 2 40 40
MacBook Pro 5 45
iPad Mini 5 8 53
IPhone 15 68
Mac Pro 30 98
iPad Pro 37 135
iPad 13 148
AirPower 6 154
Apple Watch Series 5 9 163
iPod Touch 17 180
Apple TV 20 200
Numerical Description of Quantitative Variables
Measures of location, also referred to as measures of central tendency, are measures that
represent information on the data distributions with respect to the centers of the distributions.
The measures of dispersion on the other hand are measures that represent information on the
spread within the dataset (Douglas, William, & Samuel, 2012).
Measures of location are; mean, median and mode. Mean refers to the average value of a
variable computed by dividing the total value by the count value. Median refers to the centrally
placed value in a set of values of a variable. Mode refers to the value that occurs most frequently
in a set of values of a variable. Measure of dispersion are; range, variance and standard
deviation. Range refers to the difference between the highest value and the lowest value of a
variable. Variance is a measure representing the average of the square of the deviations from the
mean value of a variable. Standard deviation refers to the square root of the variance of a
variable (Douglas, William, & Samuel, 2012).
Consider the value of the share prices of BP for the first five months of 2019 given in
Table 3: BP Share Prices and Measures of Location below. The measures of location are also
indicated in the table.
3