Statistics Definitions Flashcards
What is Descriptive Statistics ?
Summary statistic that quantively describe /summarise features of a collection of information
What is Inferential Statistics ?
Makes inferences /prediction about a population based on a sample of data taken from the population in questions ?
How would you calculate the Variance ?
Sqaure root of Standard Deviation
variance is the expectation of the squared deviation of a random variable from its mean. Informally, it measures how far a set of (random) numbers are spread out from their average value.
Standard Deviation
the standard deviation is a measure that is used to quantify the amount of variation or dispersion of a set of data values
What is the Standard Error and how is it calculated ?
SD divided by sample size
approximate standard deviation of a statistical sample population.
How Would you find 95 %?
Standard Error x2
How would you know data Is distributed ?
Curve and the mean median is similar
How do you calculate the Coefficient variation ?
divide the standard deviation by the mean and multiply by 100
Tell you how much variable something is between individuals of that same group.
Elephant 70l per min and SD =10 L per min
Cv= 10/70 =14%
Human 6 L per min SD
1/6=0.17=17%
Conclude; The variance for Human is more variable than the elephant.
Chi Square what is it ?
Is a statical method used on assessing the goodness of it between a state of observed values .
Used to analyse data that are counst of the number of things in different cateogories .
What is Destriptive Statitics ?
Descriptive: procedure for organising, summarizing and
describing data
The mean height of women in the lecture theatre is 165 cm
The average blood sugar level of a person is 90 mg / 100 ml
What is Inferential methods?
Inferential: methods for making inferences about a larger group
of individuals (population) on the basis of data
collected on a much smaller group (sample)
Students who spend more time revising get better grades
What happens if the t value is grater than the critical value ?
We have a significant results our p value is lower than the p value threshold.
