I'm creating a cheat sheet for statistical measures. Please help making it complete:
How does ... effect mean, median, mode, range, and std. dev.?
1) Add constant: Add same constant to mean, median, mode; range and std. dev. not affected.
2) Multiply with constant: Multiply mean, median, mode, range, std. dev. with the constant.
(In general: A linear transformation y=ax+b affects location measures like mean, median, and mode in the same way, but dispersion measures only affected by the multiplicative factor a.)
3) Changing the sample?
I need help with 3)
How do mean/median/mode/std.dev. change?
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If you add [a positive integer]:
Mean: increases (by the amount of the contant)
Median: increases (by the amount of the constant)
mode: increases (by the amount of the constant)
range: unchanged
std. dev: unchanged
If you multiply [by a positive integer]:
Mean: increases (by a factor of the contant)
Median: increases (by a factor of the constant)
mode: increases (by a factor of the constant)
range: increases (by a factor of the constant)
std. dev: increases (by a factor of the constant)
Not sure what you mean by question 3.
Also, just a note on cheat sheets. Make sure you use them as a reminder, but try to remember them while doing your problem - look to your cheat sheet after you work through the problem.
Mean: increases (by the amount of the contant)
Median: increases (by the amount of the constant)
mode: increases (by the amount of the constant)
range: unchanged
std. dev: unchanged
If you multiply [by a positive integer]:
Mean: increases (by a factor of the contant)
Median: increases (by a factor of the constant)
mode: increases (by a factor of the constant)
range: increases (by a factor of the constant)
std. dev: increases (by a factor of the constant)
Not sure what you mean by question 3.
Also, just a note on cheat sheets. Make sure you use them as a reminder, but try to remember them while doing your problem - look to your cheat sheet after you work through the problem.
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Thanks!
As for 3., my question is how the statistical measures are affected when changing the sample, for example:
- Changing the size of the sample by adding or removing an object to/from the sample
- Transforming one or n objects from the sample (by adding/subtracting/multiplying)
As for 3., my question is how the statistical measures are affected when changing the sample, for example:
- Changing the size of the sample by adding or removing an object to/from the sample
- Transforming one or n objects from the sample (by adding/subtracting/multiplying)