ACTUAL Exam Questions and CORRECT
Answers
Variable - CORRECT ANSWER - Quantity with a value to quality that can vary
Random variation - CORRECT ANSWER - Differences between variables governed by
chance
Nominal data - CORRECT ANSWER - Consists of simple labels/categories with no order
Ordinal Data - CORRECT ANSWER - Consists of categories with a natural order
Metric Data - CORRECT ANSWER - Consists of precisely defines values
All spaces between adjacent values are the same
Qualitative - CORRECT ANSWER - Nominal and ordinal values
Quantitative - CORRECT ANSWER - Counting or measuring - numbers
Proportions - CORRECT ANSWER - Ratio in which numerator is included in denominator -
%
Numerator - CORRECT ANSWER - Upper portion of a fraction
Denominator - CORRECT ANSWER - Lower portion of a fraction - population at risk in the
calculation
,Person Time - CORRECT ANSWER - Combines persons and time as the denominator in
incidence/mortatilty rates - when people are at risk of dying for varying periods
Ratios - CORRECT ANSWER - Compares frequencies of categories
Rate - CORRECT ANSWER - Measure of the frequency of the occurrence of a phenomenon
Normal Distribution - CORRECT ANSWER - Smooth symmetrical bell shaped curve
Mode - CORRECT ANSWER - Value that occurs most frequently
Median - CORRECT ANSWER - Middle value after arranged in ascending order
Mean - CORRECT ANSWER - Sum of all / number of values
Skewness - CORRECT ANSWER - Measurement of asymmetry
-ve skew = to the right
+ve skew = to the left
Variance - CORRECT ANSWER - Measure of the spread of values away from the mean
Range - CORRECT ANSWER - Difference between largest and smallest values
Interquartile range - CORRECT ANSWER - Difference between lowest 25% and highest 25%
of values
Semi-quartile range - CORRECT ANSWER - Average distance of the 1st and 3rd quartiles
from the mean
, Standard deviation - CORRECT ANSWER - Degree of variation in a set of data values,
relative to the mean
Standard Error - CORRECT ANSWER - Measure of the deviation of the sample mean from
the true population mean (big samples reduce standard error)
Confidence interval - CORRECT ANSWER - Range that is likely to contain the true
population value
Null Hypothesis - CORRECT ANSWER - No difference between the groups being tested
Type I error - CORRECT ANSWER - A difference is found when there isn't one - Wrongly
reject a true null hypothesis
Type II error - CORRECT ANSWER - No difference is found when one exists - Wrongly
accepting a false null hypothesis
Power - CORRECT ANSWER - Probability that a study will detect a statistically significant
difference
P values - CORRECT ANSWER - How likely it is that a hypothesis is true
Regression Coefficient - CORRECT ANSWER - Describes the relationship between 2
variables
- Slope of the line of best fit on a graph
Correlation coefficient - CORRECT ANSWER - Linear relationship between 2 values - the
strength of this relationship