Definitions Flashcards
Orthocentre
Points where the altitudes intersect
Altitude
Drawn from a vertex to the opposite side such that it forms a right angle
Circumcircle
The circle that passes through all 3 vertices of a triangle
Circumcentre
The point where the triangle’s 3 perpendicular bisectors meets
Incircle
The largest circle that will fit inside the triangle. Each of the triangle’s 3 sides is a tangent to the circle
Incenter
The point where the triangle’s 3 angle bisectors meet
Axiom
A statement which we accept without any proof
Corollary
A statement that follows readily from a previous theorem
Converse
The reverse of a theorem
Proof by contradiction
A form of proof that establishes the truth or validity of a proposition by showing that the proposition being false would imply a contradiction
Mean
The sum of all the values divided by the number of values
Median
The middle value when the values are arranged in order
Mode
The value that has the greatest frequency
Range
The difference between the maximum and minimum value of a set
Lower quartile
One quarter of the values in a ranked set of values are less than or equal to the median
Second quartile
The median
Upper quartile
3 quarters of the values in a ranked set of values are more than or equal to the median
Z-scores
The number of standard deviations a given value x is above or below the mean of a given data set
Z = χ-γ / σ
Observational study
The researcher collects the information of interest but does not influence events
Case-control study
Two groups are compared one (the case) and one (the control)
Explanatory variable
Response variable
In the case of a drug trial, the drug is called the explanatory variable and the effect of the drug is called the response variable
Categorical data
Questions that cannot be answered by numbers provide categorical data
Ordinal vs nominal
Ordinal can be ordered
Nominal cannot
Numerical data
Questions that can be answered by numbers provide numerical data