Lecture One (t1) 23/09 Flashcards
What is the classification of data
process of organising data into categories based on attributes
What are decisions based on?
Limited information
Why is there uncertainty when making decisions?
We are never given the full amount of information - we base decisions on small samples
What must accountants do to try make accurate decisions?
need to select a portion of records for auditing purposes
Can decisions made always be accuate?
No, all of the variables cannot be taken into account = uncertainty = decisions may not be accurate
for e.g. analysing a company u cant analyse the whole time they have been trading - since 1900s because of many reasons -therefore u don’t have all of the information
What must be done to ensure data to be efficient?
Now in this day and age there is LARGE amounts of data: eg internet etc
Therefore INORDER TO BE EFFICENT: DATA MUST BE SUMMARISED EFFICENTLY!
How can you summarize 10 years of monthly data points into a single page
Using charts - “A good picture is worth a thousand words”
What is a histogram
a graph type that groups data into specific buckets - e.g. what has in common = grouped
e.g. Students born in different months = split the students into buckets of their own birth months
What is data?
a collection of numbers / characters / words / text - in raw or organised form to represent facts or information.
What can data be used for
use this data to make an inference of certain things
What is numerical data?
values that represent measured or counted quantities as a number
What is numerical data also known as
Quantitative data
What are the two types of numerical data
Continuous and Discrete
What is Continuous data
data that can be measured/ take on any numerical value in specified range of values
e.g. weight can be any between 100kg
What is discrete data
numerical values that are resulted from a counting process
e.g. stock prices/ auction prices - to avoid small bets (must be larger/equal to
a certain value - they increase by a certain amount
What is categorical data?
set of data that has been broken up into different categories, can be used to label and divide a dataset into groups
what is categorical data also known as?
qualitative data
What are the two types of categorical data?
Nominal and Ordinal
What is nominal data?
categorial values, that aren’t numerical -label variations without numbers, values are unordered, mutually exclusive ,
they can be represented by numbers but wont impact the data.
eg. gender, equality, eye colour.
Why are nominal data mutually exclusive
each category is separate and cannot occur at the same time
What is ordinal data?
categorical values that can be logically order or ranked
eg. best-worst,
What are the main categories of numerical data?
Cross-sectional data, Time series data, Panel data
What is cross sectional data?
a list of observations of specific values from multiple observation units given at a point in time
meaning u fix the time period - eg analysing the age of ALL uni students TODAY
What is time series data?
sequence of observations of a SINGLE specific variable collected over time > at discrete and typically equal spaced intervals of time
analysing info from something MORE specific -eg analysing all students studying fin and account ages. So NOT the time. Just the course..
What is panel data?
a mix of time series and cross sectional data
used in financial analysis and modeling.
e.g. average age of students today across the different courses ( specifically finance and data course)
Data in ________ form are not usually easy to use for __________ ___________
Data in raw form are not usually easy to use for decision making
What is be dependent on the type of graph to use
the variable being summarized
What graphs can be used for categorical values?
-Frequency distribution
-Cross table
-Bar chart
-Pie Chart
-Pareto Diagram
What graphs can be used for numerical values?
-Line chart
-Frequency distribution
-Histogram and ogive
-Stem and leaf display
-Scatter plots
How to work out percentage
(value/total value) x100
What is frequency distribution
a list or table containing class groupings (categories or ranges within which the data falls - creating samples)
What does frequency distribution do?
its a way of summarizing data - it condenses the raw data into a more useful form
why is frequency distribution good
allows for quick visual interpretation of data
what is a graph in a frequency distribution called
histogram
