z-score

For z-score calculation, please enter numerical data separated with comma (or space, tab, semicolon, or newline). For example: 884.7 954.3 177.0 497.8 846.4 742.8 429.5 -229.9 -105.4 153.5 -223.4 997.2 595.6



Z-score

Z-score (or standard score) is the transform of items x via the formula:

z=σxμ
where:

μ is the mean of the population;
σ is the standard deviation of the population.
The absolute value of z represents the distance between the raw score and the population mean in units of the standard deviation. z is negative when the raw score is below the mean, positive when above.

How to enter data as a frequency table?

Simple. Write data elements (separated by spaces or commas, etc.), then write f: and further write the frequency of each data item. Each element must have a defined frequency that counts numbers before and after symbol f: must be equal. For example:

1.1 2.5 3.99
f: 5 10 15

How to enter grouped data?

Grouped data are formed by aggregating individual data into groups so that a frequency distribution of these groups serves as a convenient means of summarizing or analyzing the data.

groupfrequency
10-205
20-3010
30-4015
This grouped data you can enter:
10-20 20-30 30-40
f: 5 10 15

How to enter data as a cumulative frequency table?

Similar to a frequency table, but instead, f: write cf: in the second line. For example:

10 20 30 40 50 60 70 80
cf: 5 13 20 32 60 80 90 100


The cumulative frequency is calculated by adding each frequency from a frequency distribution table to the sum of its predecessors. The last value will always equal the total for all observations since the calculator will have already added all frequencies to the previous total.

Practice problems from statistics:



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