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What are two examples of description statistics?
 1. Averages
 2. Percentages

A __________is a descriptive statistic calculated from population data
Parameter

The 4 levels of measurement are
 1. nominal
 2. ordinal
 3. interval
 4. ratio

_________ is the lowest level of measurement and involves assigning #'s to classify characteristics into categories. The numbers do not have mathematical meaning
Nominal

Give 3 examples of nominal measurements.
 1. gender
 2. blood type
 3. marital status

The #'s assigned in nominal measurement a. have or b. do not have quantitative meaning
b. do not have

Nominal measurements must be classifiable into 1 and only 1 category. Thus they must be___________ and __________.
For example, 1=married, 2=separated or divorced, 3=widowed.
 mutually exclusive
 collectively exhaustive

_________ measurement goes beyond categorization and involves sorting people based on their relative ranking on an attribute
Ordinal

In an ordinal measurement, we only know the ________ ranking.
Examples of this type of measurement include: ____ _____
 relative
 frequency counts
 percentages

________ measurement occurs when researchers can specify rank ordering on an attribute and can assume equivalent distance between them
Interval

An example of an interval measurement is____
Farenheit Temp scale

Interval measurements are more informative than ordinal ones, but they do not convey _______ magnitudes, because there is no rational zero point.
absolute

Example of interval measurements is______
psychological and educational testing

In _________ measurement we can meaningfullly calculate an average which expands our analytic possibilities
interval

________ measurement is considered the highest level and provides information about ordering on the critical attribute, the intervals between objects, AND the absolute magnitude of the attribute because they have a rational, meaningful zero.
Ratio

An example of a ratio measure is _____
Weight

A _________ distribution is a systematic arrangment of values from the lowest to highest, together with a count of the number of times each value was obtained
Frequency

Frequency distributions consist of 2 values;
_____ the observed value
______ the frequency of cases at each value

Sum of f's =_____
N (total sample size)

Examples of graphs that display interval and ratio level data
Histograms and Frequency polygons

Frequency polygons can assume many shapes. A _______ distribution has two equal halves and a _________ distrubution has a peak that is off center and a tail longer on one side than the other.

When the tail of a skewed distribution points to the right, the distribution is _________.
positively skewed

When the tail of the distribtion points to the left, the distribution is _________
negatively skewed

Age at death is an example of a ________ skewed attribute.
negatively

A ________ distribution has a symmetrical peak.
Normal (Bell Curve or Gaussian distribution)

The 3 measures of central tendency is are:
____, ______ and ________

The _____ is the most frequently occurring score in a central distribution
Mode

The ________is the point in a distribution above which and below which 50 % of cases fall.
Median

Modes are a quick way to determine a ________ score, but are rather _____

The ______ is used primarily to describe typical values for nominallevel measures.
Mode

The value that divides the cases exactly in half is the ________ for the set of numbers.
Median

The ______ is the sum of all scores, divided by the number of scores.
Mean (M) or X (with line over it)

Another name for the mean is the ______.
average

The ______ is the most widely used measure of central tendency. It is the most ______because if repeated samples were drawn from a population, means would fluctuate less than modes or medians.

If the goal is to understand what is "typical" in a sample, the _______ may be the best measure of central tendency. As in a the income level of a group.
Median

When a distribution is symmetric and unimodal, the three indexes of central tendency _______
coincide

In a skewed distribution, the mean , median and mode will _________
Differ

In a skewed distribution the mean always pulls in the direction of the long ________
tail

The ________ is most suited for nominal measures.
Mode

Both the ____ and ____ are suitable for ordinal measures.
(measures of central tendency)

The ________ is appropriate for interval and ration measures.
( a measure of central tendency)
Mean

______ is the measure of how spread out or dispersed the data are.
Variability

The _______ is the highest score minus the lowest score.
Range

The range is ________ because it is based on only two numbers.
Unstable.

_______ is a measure of variability used for interval or ratiolevel data. It indicates the average amount of deviation of values from the mean and is calculated in every score.
Standard Deviation

A _______ score is the difference between an individual score and the mean.

If a person weighed 150 lbs and the sample mean were 140. The person's deviation score would be______
+ 10.

Deviations above the mean always ______ deviations below the mean, so that the net sum of them is 0.
Balance

_______ is the value of the standard deviation before a square root has been taken, and it is a related index of variability.
Variance

In a normal or near normal distribution there are roughly ______ SD's above and below the mean.
3.

The ______ is a useful variability index for describing a distribution and interpreting individual scores.
Standard Deviation

Like the mean, the SD is a _______ estimate of a parameter and is the preferred index of a distribution's __________

