Appendix B Flashcards
chi-square test
goodness of fit or contingency test. Test of significance designed to determine if the difference in observed and expected frequencies are significant within a selected degree of probability (frequency data vs continuous data)
continuous variable
infinite number values possible (ex. measurement of haemoglobin in blood may be in whole grams or fractional units)
discrete variable
fixed numerical values with no intermediates possible (ex. number of toes, number of trees, number of white blood cells)
dispersion
scatter of values from a central point
histogram
graph of a frequency distribution of a continuous variable
interpolation
predicts values within range of values measured but which do not actually exist in the set
Mean
denoted by X with line on top
measurement error
reflects discrepancy between a measurement and the true value of the variable being measured
median
middle value in an ordered set of values (half values are less than and half more than)
mode
most frequently occurring value
normal distribution
a theoretical frequency distribution that is bell shaped and symmetrical
population
in stats, all possible values of a particular variable in all sampling units of a particular group
precision
nearness of values of successive measurements of the same specimen
range
largest values - smallest values
scientific notation
write number as factors of powers of 10
significant figures
reflects the accuracy for which we are able to measure
standard deviation
a measure of the dispersion of a set of data about the mean (calculated as the square root of the variance)
- average size of the deviation from the mean
standard error
a measure of how reliable the sample mean is as an approximation to the population mean (standard deviation/square root of sample size)