DATA MANAGEMENT Flashcards
a branch of mathematics that deals with data collection, organization, analysis, interpretation and presentation.
statistics
defined as the procedure of collecting, measuring, and analyzing accurate insights for research using standard validated techniques
data collection
refers to the method of classifying and organizing data sets to make them more useful, it can be applied to physical records or digital records.
data organization
process of inspecting, cleansing, transforming, and modeling data with the goal of discovering useful information, informing conclusions, and supporting decision-making
data analysis
process of assigning meaning to the collected information and determining the conclusions, significance, and implications of the findings.
interpretation of the data
refers to the organization of data into tables, graphs or charts, so that logical and statistical conclusions can be derived from the collected measurements
presentation of the data
two kinds of variables
qualitative
quantitative
also called as categorical variables are variables that are not numerical. It describes data that fits into categories.
Qualitative variables
are numerical. It can be ranked and has order
Quantitative variables
no. of students present
Discrete
no. of re marbles in a jar
Discrete
no. of heads when flipping three coins
Discrete
students’ grade level
Discrete
height of students in class
continuous
weight of students in class
continuous
time it takes to get to school
continuous
distance traveled between classes
continuous
Types of statistical data
numerical
categorical
These data have meaning as a measurement such as a person’s height, weight, IQ, or blood pressure or shares of stocks a person owns.
Numerical Data
represent characteristics such as a person’s gender, marital status, hometown, or the types of motives they like.
Categorical Data
This can take on numerical values (such as 1 indicating male and
2 indicating female) but those numbers don’t have mathematical meaning.
Categorical Data
Four level of measurements
Nominal
ordinal
interval
ratio
the lowest of the four ways to characterize the data. it deals with names, categories, or labels.
Nominal
the data at this level can be ordered but no differences between the data
ordinal
deals with data that can be ordered, and in which differences between the data does make sense. But data at this level has no starting point.
interval
the highest level of measurement. data possess all the features of the interval level, in addition to an absolute zero. due to the presence of a zero, it now makes sense to compare the ratios of the measurements
ratio
Methods of collecting data
in-person interviews
mail surveys
phone surveys
web/online surveys
Pros: in depth and a high degree of confidence on the data
in-person interviews
Cons: Time consuming, expensive and can be dismissed as anecdotal
in-person interviews
Pros: Can reach anyone and everyone – no barrier
Mail surveys
Cons: Expensive, cannot self-administer, need to hire an agency
Phone survey
Cons: Expensive, data collection errors, lag time
Mail surveys
Pros: High degree of confidence on the data collected, reach almost everyone
Phone survey
Pros: Cheap. can self-administer, very low probability of data errors
Web/Online survey
Cons: Not all your customer might have an email address/be on the internet, customers may be worry of divulging information online
Web/Online survey
Three ways of presenting data
textual
tabular
graphical
this method comprises data presentation with the help of a paragraph or a number of paragraphs
textual
the method of presenting data using statistical table. a systematic organization of data in columns and rows
tabular
a chart representing the quantitative variations or changes of variables in pictorial or diagrammatic form
graphical
the rate that measures how often something occurs
frequency
a pictorial representation of statistical data in such a way that length of the rectangles in the graph represents the proportional value of the variable. _______ are generally used to compare the values of several variables at a time to analyze that data. The length of the bars represents the frequency of the variable and is applicable to discrete categories only.
Bar Graph
a graphical display of information that changed continuously over time. Within a line graph, there are points connecting the data to show a continuous change. The lines in a line graph can descend and ascend based on the data. We can also compare different events, situations, and information.
Line graph or line chart
type of a graph that displays data in a circular graph. the pieces of the graph are proportional to the fraction of the whole in each category. each slice of the pie is relative to the size of that category in the group as a whole. the entire pie represents 100 percent of a whole, while the pie slices represent portions of the whole
pie chart
