Hypothesis Testing: Two Sample Tests of Significance Flashcards
Scale of ordered numbers but the spacing between them is not necessarily the same
Ordinal Scale
Numbers are assigned to different variables but the number’s value doesn’t have a meaning on its own
Nominal Scale
Scale of ordered numbers with equal spacing. Includes negative numbers as has a relative zero value.
Interval Scale
Scale of ordered numbers with equal spacing that has an absolute zero value (i.e. no negative numbers)
Ratio Scale
A calculation that tests the hypothesis that two sample mans point to (or estimate) the same population mean. The term “independent” indicates that each subject is in one and only one sample.
Student’s t-test for independent samples
A calculation that tests the hypothesis that a sample mean of measurement of differences points to (or estimates) a population mean of zero. The term “related” indicates that subjects act as their own control or that two different subjects have been matched or linked in some way. Two measurements are collected per subject or pair and teh sample mean is computed by subtracting one from the other.
Student’s t-test for related samples
A sampling distribution which is formed by selecting two random samples of equal size from the same population and then constructing a distribution of the differences of the means in each sample. This sampling distribution reveals what the difference between two sample means is expected to be when no treatment effects are present.
Sampling distribution for the difference of two sample means
The standard deviation of the differences in sample means used to form a sampling distribution for the difference of two means.
Standard Error for the Difference of Means
The average of the variances of two independent samples for estimating the variance of a measurement in a population
Pooled Variance
The arithmetic mean of a sufficiently large number of iterates of independent random variables will be approximately normally distributed.
Central Limit Theorem
Variability of measurements is similar among all study groups
Homogeneous Variance
Variability of measurements differs among study groups
Heterogenous variance
The calculation that is done for an independent samples student t-test when the homogeneity of variance assumption is violated
Satterthwaite Adjustment
A test of statistical significance in which the rival hypothesis is stated in one direction
One-tail test
A test of statistical significance in which the rival hypothesis is not stated in any particular direction
Two-tailed test
