Mathematics Stack Exchange
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Questions tagged [average]

Averages summarise a set of values in one way or another. Without further qualification it most commonly refers to the arithmetic mean, but other averages such as root-mean-square exist.

In its most general definition, an average is a summary of a set of values. Normally it refers to the arithmetic mean, but other means may be employed (geometric, harmonic, etc.) or a transformation may be applied before and after taking a mean (e.g. root-mean-square).

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Averaging averages or not

I've got a big list of data that is split by industry, and 'keyword' within this. I'm trying to do an average per industry, as well as an average for overall, and wanted to check what is the most accurate way of finding averages here. I've checked…
Rosie
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Average Slope of 4 Slopes

I want to calculate tha Average Slope of 4 Slopes, but Im not too sure if this will require me to calculate the Average error when I do calculate the average of the 4 slopes. Im obviously calculating the Average as (slope $i :=…
I AM L
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How to calculate average between 2 joints?

I have $21$ joints (each joint has $2$ coordinates $(x,y)$). I would like to calculate average value to get center of all joints. And then normalize the original coordinates. How can I calculate average and normalize?
Dennis Thor
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Merging/averaging percentages

This may be a very simple question, but I'm not even sure what the correct terminology is for the procedure I am trying to do so I wasn't able to find anything else here... The scenario is that I'm writing a program that tracks completion. The…
Jace
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Why 1 / (average of series) $\ne$ average (1 / series)

I have series of two stocks prices. Let's say that stock 1 has prices: $A_1$, $A_2$, $A_3$, $A_4$, ..., $A_i$ (where $i$ is time) And stock 2 has prices: $B_1$, $B_2$, $B_3$, $B_4$, ..., $B_i$ (where $i$ is time) As stocks are higly correlated I…
Oleg Vazhnev
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Which average would make the most sense (mean, mode, median)?

I have musical data, for tuning information for notes of an instrument. For each note played, I have the cents away from in tune (-50.0 - 50.0). I'd like to display the average each note was out of tune. I'm not sure which would make the most sense…
user1218464
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Arithmetic, Harmonic or Geometric Mean?

I have a frequency spectrum of a particular phenomenon (it is the Fast Fourier Transform of the stress response in iron to an induced strain). In short, the stress oscillates and I wish to analyse the frequency of the oscillations. A typical…
William White
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Can I increase the standard deviation of a series without increasing its mean?

I have a series of values. Can I modify them in a consistent manner such that it's mean remain the same but standard deviation increase by 1? 1 is just arbitrary in this example
Boon Heng Tan
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Intuition calculating average price change

Given two products p1 and p2, each with a price per single unit and an amount per year. The question is to calculate the average change in price for both products combined. +-Product#-+-Amount_Y2011-+-Price_Y2011-+-Amount_Y2012-+-PriceY2012-+ | 1 …
eric
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Weighted Average when adding and removing items

This might be a silly question for you guys, but I've been struggling myself to handle it. Imagine we have a fish tank with: number of fishes: 1000 weighted average: 0.233 (kg) One day, I decided to remove 200 fishes having 0,5 kg of weighted…
hugalves
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Conceptual difference between weighted arithmetic mean and ordinary arithmetic mean

I'm having a hard time understanding what does these values really represents, most about the weighted mean actually. I will give an example: In a factory there's 2 equipments: Equipment 1 produces 100 tons in 10 hours Equipment 2 produces 100 tons…
João Menighin
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What is the quantity of milk in the solution?

In a milk solution of 10 lit, 2 lit of water is added thereby the concentration of milk is reduced by 15%. What is the quantity of milk in the solution? (Ans is 9) I tried: Concentration - Water added - Milk: 100 - 0 - 10 liter 85 - 0 - ? $\dfrac…
Siberan Jonah
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Given a 5% employee turnover per year: What is the average tenure time?

Is it possible, based on a given turnover rate per year (in %), to calculate the average time (in years) an employee stays in an organization? I have looked at the Coupon Collector's…
FloWEffect
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Averaging as samples come in

I feel like this is a lot easier than I'm making it, but for some reason I just can't wrap my head around it. Let's say I'm sampling a voltage, for argument's sake. I want to know the average voltage over a period of time. If I know the number of…
Brydon Gibson
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Productivity forecast

So if I have the following data available: Person A May 1 10 May 2 20 May 3 20 Person B May 1 15 Person C May 2 10 May 3 12 May 5 18 Person D May 1 10 May 2 14 May 3 18 May 4 30 May 5 5 May 8 20 May 9 …
Probs
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