Levels of Quantitative Measurement
The lowest level of measurement, which consists of assigning numbers as labels for categories. these numbers have no numerical interpretation. Example, blood type (A, B, AB, O).
What is nominal level of measurement?
Descriptive statistics that depict the spread or variability among a set of numerical data.
What are the measures of central tendency?
A score defined as the difference between the raw score and the mean of that distribution (the sum of the deviated scores in a distribution always equal 0).
What is a deviated score?
The dependent variable is measured on an interval-ratio scale and is normally distributed in the population and groups being mutually exclusive (independent of each other). Accomplished through random sampling.
What are parametric procedures?
A parameter estimation evaluated by a single number or an interval. Example, a sample mean age of 18 years.
What is the point estimate?
A level of measurement that yields rank order data. Example, Likert scale.
What is ordinal level of measurement?
The most commonly used measure of central tendency and is often associated with the term average.
What is the mean?
A measure of variability that is the difference between the lowest and highest values in a distribution. It is calculated by subtracting the lowest score in the distribution from the highest.
What is the range?
A parametric procedure using interval-ratio data to test for a relationship between 2 variables. The correlation can be positive or negative and decimals closer to 1 are highly correlated.
What is a Pearson product-moment correlation or Pearson r?
A range of values that has some specified probability (ex., 0.95-0.99) of including a population parameter.
What is a confidence interval?
Level of measurement characterized by a constant unit of measurement or equal distances between points on a scale. Example, no true zero such as temperature.
What is interval level of measurement?
A measure of central tendency that represents the middle score in a distribution and the best measure with a skewed distribution. Example, set of scores on a pain scale of 4, 5, 5, 7, 7, and 9, (7+5)/2=6.
What is a median?
Measure of variability, which is the average squared deviation form the mean.
What is the variance?
a parametric procedure used to determine whether means in 2 groups are significantly different when scores in one group have no logical relationship with scores in the other group or independent of each other.
What is an independent t-test or pooled t-test?
The likelihood that an event will occur.
What is probability (p)?
The highest level of measurement, characterized by equal distances between scores having an absolute zero point. Example, height and weight.
What is ratio level of measurement?
The score or value that occurs most frequently in a distribution; a measure of central tendency used most often with nominal-level data (categories).
What is the mode?
The square root of the variance and the most stable measure of variability.
What is the standard deviation?
Tests typically used when data represents an ordinal or nominal scale. Also known as distribution free tests (can be used when data is skewed).
What are nonparametric procedures?
The probability (alpha) level in which the null hypotheses can be rejected with confidence and the research hypothesis can be accepted with confidence.
What is a level of confidence?
A definition that assigns meaning to a variable and the terms or procedures by which the variables are to be measured. Example, the variable education is ranked 1-4 and defined as graduate/professional training, completed college, and less than college.
What is the operational definition?
A data point isolated from other data points in a distribution of scores, which pulls the mean in the direction of those extreme values. Example, ages 23, 24, 25, and 50.
What is an outlier?
Measures that consider every score in a distribution.
What are the variance and standard deviation?
A nonparametric statistic that compares frequency of an observed occurrence with a frequency of an expected occurence.
What is Chi-square analysis?
When researchers are willing to accept statistical significance occurring by chance five times out of 100.
What is the standard level of confidence (0.05)?