Biostatistics & Epidemiology Lecture 1 Histogram, Ogive or line chart,

alchemist04's version from 2016-06-25 00:35


Question Answer
What is on Y axis (Vertical) of Histogram?The frequency that determines the bar height
What is on the X axis (Horizontal)?The classes of data (e.g 10 - 19, 20 -29 etc), use class boundaries or class midpoints. Represented by the subject's name (e.g pulse rate or height rate or BP rate)
Skewness meansLack of symmetry in the histogram
Positive skew (right skew)has more low values
Negative skew (left skew)has more upper values


Question Answer
Relative frequency histogramthe frequency is represented by proportion or percentage and not regular numbers
Normal distribution graph of Histogramthe graph has normal bell shape
Platykurtic(1) distribution is flat (2) more variability than other distribution
Leptokurtic(1) distribution peaked (2) lower variability than other distributions


Question Answer
What does a line chart tell us? (1)(1) Estimation of possible trend
What does a line chart tell us? (2)(2) present a dat for a particular period of time
What does a line chart tell us? (3)(3) can be juxtaposed w/ results from a histogram
What does a line chart tell us? (4)(4) useful for charting possible trends over time


Question Answer
Pie Chart (1)(1) depicts qualitative data as slices of a circle, in which the size of each slice is proportional to the frequency count for the category
Pie Chart (2)(2) use Pie Charts w/ qualitative data
Pie Chart (3)(3) Pie Charts is good for representing a small or large sample w/ percentages
Pie Chart (4)(4) Pie Charts are the best graphical representation of the data