Stat terms Flashcards
Range
Range is a measure of dispersion. It is defined as the difference between the highest and the lowest values.
Median
In a population or a sample, the median is the value that has just as many values above it as below it. If there are an even number of values, the median is the average of the two middle values.
Mode
The mode is a value that occurs with the greatest frequency in a population or a sample.
Standard Deviation
Average deviation from the mean. How far the scores deviate on average from the mean, positive square root of variance.
Variance
Sum of squares divided by the sample size or sample size minus one. It is average square deviation from the mean.
Mean
Average of scores
MAD
Mean Absolute Deviation
The mean absolute deviation of a set of data is the average distance
between each data value and the mean.
It includes (1) minimum, (2) maximum, (3) median (or second quartile), (4) the first quartile, and (5) the third quartile.
Box-and-Whisker plot
A way of presenting measure of central tendency on variability graphically. It indicate shape of distribution.
Standard score
The distance away from the mean in standard deviation unit. It is presented as “z”.
Population
A set of all values, scores or organisms of interest. It includes every single individual of interest.
Population Distribution
Distribution of all scores from the population
Parameter
A measurement of the characteristics of a population. No variation. It is fixed.
Random sample
Random sampling is a method of selecting a sample from a population in which all the items in the population have an equal chance of being chosen in the sample.
Sample Distribution
Collection of individual scores, theoretical probability distribution of some statistics.
Statistics
A measure of a characteristics of a sample distribution.
Dependent Variable
The variable that is being influenced. Measure of subjects behavior.
Independent Variable
The variable the experimenter manipulates.
Measurement (as a process)
How you assign the number of people and a set of rules that determine what makes up the scale.
Nominal Scale
A nominal scale is really a list of categories to which objects can be classified. It does not imply any amount. Just type or brand.
Ordinal Scale
An ordinal scale is a measurement scale that assigns values to objects based on their ranking with respect to one another.
Interval Scale
An interval scale is a measurement scale in which a certain distance along the scale means the same thing no matter where on the scale you are, but where “0” on the scale does not represent the absence of the thing being measured. Fahrenheit and Celsius temperature scales are examples.
Ratio Scale
A ratio scale is a measurement scale in which a certain distance along the scale means the same thing no matter where on the scale you are, and where “0” on the scale represents the absence of the thing being measured.
Discrete Variable
離散変数. A variable that may assume only a countable, and usually finite, number of values.
Continuous Variable
If a variable can take on any value between its minimum value and its maximum value, it is called a continuous variable; otherwise, it is called a discrete variable.
Continuous Variable
If a variable can take on any value between its minimum value and its maximum value, it is called a continuous variable; otherwise, it is called a discrete variable.
Normal Distribution
The normal distribution is a probability density which is bell-shaped, symmetrical, and single peaked. The mean, median and mode coincide and lie at the center of the distribution. The two tails extend indefinitely and never touch the x-axis (asymptotic to the x-axis). A normal distribution is fully specified by two parameters - mean and the standard deviation.
