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This is a surprisingly difficult question, partly perhaps because of the ambiguous term 'ordinal'. For instance, horse-race finishes are ordinal--horses usually finish first, second, etc., with no ties; pure order data gives no information about gaps between horses. For such data--the purest form of ordinal data--talk about variability is meaningless. You need data with 'ties' or repeated 'values'--more cases than ordered categories--to talk about variability meaningfully.

If you do have repeated values, one option is to fall back and use nominal variability measures--the Index of Qualitative Variation is one; information statistics also work; and there's always the frequency/percentage table. They don't 'measure' concentration along the categoric order, obviously.

Disappointingly many websites recommend using the range or interquartile range, presumably calculated by assigning numbers to the ordered categories and subtracting. These indices are very dangerous if you assume only qualitative order among categories. This is obviously flawed--if you don't know how far categories are separated, subtracting numbers is flat invalid. For instance, rank states in the US by size--Alaska is 1, RI is 50--and consider the fact that a group from AK, TX, and CA has a range of 2 and a group from NJ and MA has range of 3 [47 - 44]. First, those numbers are really meaningless; second, they sure misrepresent relations among state size differences. Unless you trust that your 'ordinal' categories are pretty close to equal intervals apart--what we call 'quasi-interval'--you simply cannot use range validly to measure ordinal variability. The same reasoning applies to inter-quartile range. You might as well use variance, since describing 'skew' and 'outliers' for ordinal data is very dangerous, itself.

More valid ordinal measures do exist--I cannot recall them. But when you choose an index, take care to examine how it is treating the numbers or other ordering symbols it trades on. Invalidity is rife.

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Q: What is the appropriate measure of variability for ordinal data?
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IS GPA nominal data or ordinal?

It is ordinal.


Should The mean or median be used in ordinal data?

The median is used when reporting ordinal data.


What measure of central tendency may not exist for all numeric data sets?

Measurement Scale Best measure of the 'middle' Numerical mode Ordinal Median Interval Symmetrical data- mean skewed data median Ratio Symmetrical data- Mean skewed data median


What is the measure of central tendency for nominal and ordinal data?

The mode can be used with both kinds of data. The median may be used with ordinal data but great care is required if the median falls between two classes of observations.The mode can be used with both kinds of data. The median may be used with ordinal data but great care is required if the median falls between two classes of observations.The mode can be used with both kinds of data. The median may be used with ordinal data but great care is required if the median falls between two classes of observations.The mode can be used with both kinds of data. The median may be used with ordinal data but great care is required if the median falls between two classes of observations.


How do you convert ordered data to nominal data?

I think you mean ordinal data. Similar to the golf tournament, you need to determine where to "cut" (from the ordinal data) so as to divide the data into different categories (to the nominal data). For example, if the ordinal data range from 1 to 6 (where 1 = the best) and the cut is 3, then you convert all the numbers from 1 to 3 to "1" (which represents "good") and the all numbers from 4 to 6 to "2" (which represents "bad"). In other words, 1, 2, and 3 from the original ordinal data set are converted to "1" (ordinal data); whereas 4, 5, and 6 from the original date set now become "2" (ordinal data). Eddie T.C. Lam

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What is the appropriate measure of average that must be used?

The appropriate measure of average that must be used depends on the type of data being analyzed and the research question being asked. For example, if the data is numerical and normally distributed, the mean is often used as the measure of average. If the data includes outliers or is not normally distributed, the median may be a more appropriate measure of average. Similarly, if the data is categorical or ordinal, the mode may be the appropriate measure of average.


How does finding the IQR hep you identify the variability of set of data?

The IQR gives the range of the middle half of the data and, in that respect, it is a measure of the variability of the data.


What is the best measure of variability?

The best measure of variability depends on the specific characteristics of the data. Common measures include the range, standard deviation, and variance. The choice of measure should be made based on the distribution of the data and the research question being addressed.


Which measure of central tendency cannot be applied to ordinal data?

The mean cannot be used with ordinal data. The best measure of central tendency for ordinal data is usually the median. A common example of ordinal data is the scale you see in many surveys. 1=Strongly disagree; 2=Disagree; 3=Neutral; 4=Agree; 5=Strongly agree. The mean would have not meaning here ( no pun intended) The median is simple the middle value. The mode does have meaning.


IS GPA nominal data or ordinal?

It is ordinal.


What is ordinal statistics?

Ordinal statistics or data is classified as ordinal if the values can be rated on a scale or put i order. Ordinal data can be counted but never measured.


Is asking your birth year a ordinal data?

No, but the answers provide ordinal data.


Does the coefficient of variation measure variability in a data set relative to the size of the arithmetic mean?

Yes.


Should The mean or median be used in ordinal data?

The median is used when reporting ordinal data.


Would you use mode and median measure for the central location would be appropriate to use for the data generated by a questionnaire?

If the information collected is nominative - eg what is your favourite colour - you have no choice but to use mode. A median may be an appropriate choice is there are outliers or if the data are on an ordinal but not in interval scale - eg small/medium/large or strongly disagree/disagree/agree/strongly agree.


What measure of central tendency may not exist for all numeric data sets?

Measurement Scale Best measure of the 'middle' Numerical mode Ordinal Median Interval Symmetrical data- mean skewed data median Ratio Symmetrical data- Mean skewed data median


In mathematics central tendency is the tendency of data values to cluster around some central value. What does a measure of variability tell you about the central tendency of a set of data Explain.?

The measure of variability tells you how close to the central value the data values lie: that is whether the cluster is tightly packed around the central value of spread out over a large range of values.