HesapHanem

Cumulative Frequency Calculator

Enter class frequencies to build the cumulative frequency.

How it is calculated

Enter the class frequencies in order, separated by commas, spaces or both. The tool keeps a running total: Ci = f1 + f2 + … + fi, so each cumulative value equals the previous one plus the new frequency. The last value is also reported as the total, which is the number of observations in the data. Order matters because the running total follows the order you type, so list the classes from the lowest to the highest interval. Frequencies are counts, so every entry must be a whole number of zero or more: a negative value, a decimal such as 2.5, or anything that is not a number (including semicolons between values) gives no result. Because the comma is a separator, 2,5 is read as two entries, 2 and 5. Zeros are allowed for empty classes.

Worked example

A teacher groups test marks into five intervals with frequencies 3, 7, 12, 8, 5. The first class has 3. The second adds 7 to give 3 + 7 = 10. The third adds 12 to give 22. The fourth adds 8 to give 30. The fifth adds 5 to give 35. The cumulative frequencies are 3, 10, 22, 30, 35 and the total is 35 students. Half of 35 is 17.5, which is first passed in the third class, so the median lies in the third interval.

Try this example →

Common mistakes

  • Typing the classes out of order. The running total follows your order, so the intervals must be sorted from lowest to highest before you enter them.
  • Entering cumulative values instead of the individual frequencies. If you type 3, 10, 22, 30, 35 the tool adds them again and the totals are far too large.
  • Using a decimal comma such as 2,5. The comma splits it into 2 and 5, which silently adds a class; and a decimal point such as 2.5 is rejected because a count must be whole.
  • Using semicolons or text between the numbers. Commas, semicolons, spaces and line breaks separate values, and any non-number makes the whole list give no result.
  • Entering a negative frequency through a typo. It is rejected, because a real count cannot be below zero.

About this calculator

Cumulative frequency is a running total: you take a list of class frequencies (how many data points fall into each category or interval) and, for each class, add its own count to the sum of every count that came before it. The last cumulative value always equals the total number of observations in the whole data set.

Plotting cumulative frequency against class boundaries produces what statisticians call an ogive, a smooth rising curve used to read off the median and quartiles graphically without needing the raw, ungrouped data — you simply find where the curve crosses the desired cumulative count and read across to the value. This makes cumulative frequency a standard tool in descriptive statistics courses and in summarizing survey or grouped measurement data where only bucketed counts are available.

Was this helpful?

You can pick up to 3 reactions.

Comments

  • Be the first to comment.

Popular calculators

Loan Calculator

Monthly payment, total interest and full amortization schedule.

Percentage Calculator

Percent change, percent of, and ratio calculations.

Discount Calculator

Calculate final price, savings, and discount amount.

BMI Calculator

Body mass index from height and weight (metric or imperial).

Age Calculator

Compute your exact age in years, months and days from a birth date.

Compound Interest Calculator

Calculate the final amount and interest earned with compounding.

All Calculators