Linked Questions

1 vote
2 answers
275 views

Geometric vs. arithmetic mean [duplicate]

I'm not sure if this is the best place for this question, but when averaging data, how do you know if the geometric or arithmetic mean is more appropriate for taking the average? Do you need to know ...
user avatar
0 votes
0 answers
49 views

Back transformed exp(log amount) showing different amount than the untransformed one [duplicate]

...
Doug Fir's user avatar
  • 1,568
0 votes
0 answers
47 views

Arithmetic and Geometric Means [duplicate]

The arithmetic and geometric averages provide a summary of historical performance. They are both unique in calculation and contain biases (as stated by my lecturer). My question is where exactly are ...
Gustavo Louis G. Montańo's user avatar
0 votes
0 answers
30 views

Is there a name for "product divided by arithmetic mean"? [duplicate]

Consider two rates, $0 < x, y < 1$. How would one call $z$, if $z = \frac{x*y}{(x+y)/2} = \frac{2*x*y}{x+y}$? Is there a relationship with other means, such as the Inequality of arithmetic ...
bers's user avatar
  • 143
45 votes
5 answers
128k views

What is the difference between "mean value" and "average"?

Wikipedia explains: For a data set, the mean is the sum of the values divided by the number of values. This definition however corresponds to what I call "average" (at least that's what I remember ...
neydroydrec's user avatar
48 votes
7 answers
23k views

Combining probabilities/information from different sources

Lets say I have three independent sources and each of them make predictions for the weather tomorrow. The first one says that the probability of rain tomorrow is 0, then the second one says that the ...
Biela Diela's user avatar
8 votes
4 answers
11k views

What are the different types of averages?

I know there are three types of averaging methods in statistics: Mean, Mode and Median. Are there any other type of averaging methods that statisticians use? How do I know which method is best for ...
gpuguy's user avatar
  • 1,123
7 votes
3 answers
1k views

When to use Mean(X/Y) versus Mean(X)/Mean(Y)?

So, I understand that for two vectors of numbers X and Y the mean of X/Y is different from the mean of X divided by the mean of Y. But I'm not sure when it is appropriate to use each. Specifically, I ...
Plopern's user avatar
  • 73
13 votes
1 answer
15k views

"Averaging" variances

I need to obtain some sort of "average" among a list of variances, but have trouble coming up with a reasonable solution. There is an interesting discussion about the differences among the three ...
bluepole's user avatar
  • 2,699
5 votes
3 answers
6k views

geometric mean and the normal distribution

If you have data that are sampled from a normal distribution, what is the relationship between the arithmetic and geometric means? Would it ever make sense to report the geometric mean instead of the ...
Bassam's user avatar
  • 161
7 votes
2 answers
539 views

Just "take the average" they say. It's not that straightforward, right?

I have an acquaintance who does not study statistics and doesn't understand that summing data and dividing by the number of data is a summary statistic, i.e. that information is lost. For example, ...
call-in-co's user avatar
  • 1,016
8 votes
1 answer
6k views

In calculating the F-measure with precision and recall, why is the harmonic mean used?

The article for F-measure in Wikipedia says: The traditional F-measure or balanced F-score (F1 score) is the harmonic mean of precision and recall: $F_1=2\times\frac{precision \times recall}{...
e9t's user avatar
  • 250
1 vote
1 answer
6k views

How can I get an average of percentages?

I can't seem to find an answer to my exact question. I want find how much on average a stock or the stock market goes up during an up week (or month) and down during a down week (or month). Let's say ...
Eliot's user avatar
  • 11
5 votes
1 answer
2k views

Arithmetic vs Geometric Mean

There are verbal suggestions everywhere on when one should use a geometric average or when an arithmetic average should be preferred, but I can't find any formal statistical treatment of this question....
user41838's user avatar
  • 531
2 votes
0 answers
1k views

What kind of mean to use for a mix of negative and positive percent values?

What sort of mean can I use in calculating the average of the deviations of actuals from a forecast, which are in percent. The data look(s) like this: ...
dimitriy's user avatar
  • 35.5k

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