Statistics Flashcards
Why are statistics important
We must have evidence in the form of statistics to back up our conclusion of experiments
What is a population
Entire collection of units, items or individuals under investigation
What is a sample
Subset of the population which we use to collect information
What is a unit
Entity which is to be measured e.g. Human, petri dish, plot of land
What is a variable
Any characteristic or attribute which may vary from one unit in the population to another
What is an observation
It is the value that a variable has been found to have on a particular individual unit
What does a data set contain
Row = unit Column = variable
What is accurate data
Correct data
What is precise date
High number of decimal points to ensure precision
What is repeatability
Can the person who carried out the experiment repeat the results
What is reproducibility
can someone else who hasn’t carried out the experiment reproduce the same results
What are non sampling errors
they cover all errors other than those due to sampling a subset of the population
what are the 4 different type of non sampling errors
Coverage
Non Responsive
Measurement
Data Handling
What is a coverage error
an inadequate sample to be able to represent the entire population is taken
what is a non responsive erro
failure to obtain information from a sampling unit
What is a measurement failure
for some reason the recorded response differs from the true value
What is a data handling error
an error associated with the transcribing of data across mediums of storage
What are the two types of variables
Qualitative
Quantitative
What is a qualitative variable
A qualitative variable represents a characteristic
What is a quantitative variable
A quantitative variable is numerical in nature
Think Quantity
What are the two types of qualitative variable
Ordinal
Nominal
What is an ordinal variable
natural ordering
what is a nominal variable
no natural ordering
what are the two types of quantitative variable
discrete
continuous
What is a discrete variable
take only countable numbers as possible values
what is a continuous variable
unlimited number of possible values
