Can we take average of average?

Can we take average of average?

A fact that we teach in our OLAP class is that you can’t take the average of averages and hope it will match the average. It is only true if all of the averages are computed over sets having the same cardinality, otherwise it is false. …

How do you calculate multiple percentages?

Multiply the original price – also known as your base – by that percentage. On a calculator, for the fishing rod example, you’d put in 130, then the calculator’s multiplication sign (usually x or *), then a decimal point, then the percentage you have to pay.

How do I calculate the average percentage increase?

To calculate the percentage increase:

  1. First: work out the difference (increase) between the two numbers you are comparing.
  2. Increase = New Number – Original Number.
  3. Then: divide the increase by the original number and multiply the answer by 100.
  4. % increase = Increase ÷ Original Number × 100.

How do I calculate annual increase?

To calculate the annual growth rate formula, follow these steps:

  1. Find the ending value of the amount you are averaging.
  2. Find the beginning value of the amount you are averaging.
  3. Divide the ending value by the beginning value.
  4. Subtract the new value by one.
  5. Use the decimal to find the percentage of annual growth.

How do you calculate population size?

Population size: The total number of people in the group you are trying to study. If you were taking a random sample of people across the U.S., then your population size would be about 317 million. Similarly, if you are surveying your company, the size of the population is the total number of employees.

What is an example of growth rate?

For example, the number of manufacturing jobs in the US decreased from 15.3 million in 2002 to 11.9 million in 2012, a -22.2% growth rate. An annual growth rate is a growth rate of some quantity over a single year.

How do you calculate total population?

It can be calculated by dividing the population 0-14 years and 65 years and older by the population that is in the 15-64 year age group. Example: A community has 41,650 children under age 14 and 6,800 persons age 65 and over. The total population is 85,000.

What are 4 methods of determining population size?

Four methods of determining population size are direct and indirect observations, sampling, and mark-and-recapture studies.

What is mid year population formula?

The mid-year population is computed by letting the population increase at an annual geometric rate of 2 per cent for half a year. The mean population is computed by adding the population for the beginning of each of the twelve months and for the end of the last month, and dividing the sum by 13.

What is the formula of sample size?

n = N*X / (X + N – 1), where, X = Zα/22 *p*(1-p) / MOE2, and Zα/2 is the critical value of the Normal distribution at α/2 (e.g. for a confidence level of 95%, α is 0.05 and the critical value is 1.96), MOE is the margin of error, p is the sample proportion, and N is the population size.

How are deaths per thousand calculated?

The crude death rate is defined as “the mortality rate from all causes of death for a population,” calculated as the “[t]otal number of deaths during a given time interval” divided by the “[m]id-interval population”, per 1,000 or 100,000; for instance, the population of the U.S. was around in 2003, and in …

How do you calculate mortality rate?

To calculate a death rate the number of deaths recorded is divided by the number of people in the population, and then multiplied by 100, 1,000 or another convenient figure. The crude death rate shows the number of deaths in the total population and, for the sake of manageability, is usually calculated per 1,000.