Data Distributions Flashcards
What is normal distribution?
It is the predicted distribution when considering an equally likely set of data
What’s the shape of normal distribution?
A classic bell shaped curve
Features of normal distribution?
1 The mean median and mode all at the same point
2 The distribution symmetrical around the midpoint
3 The distribution scores or measurements either side of the midpoint is consistent and can be expressed in standard deviation
Examples of normal distribution?
All signs point to iq scores being similar due to age
For diagram of normal distribution?
Look at distribution curves booklet
When does skewed distribution occur?
If some scores are not distributed equally around the mean
-the data values trail off more sharply on one side than on the other
Why do we get positively skewed data?
-Where something in our score has an anomaly
-Most scores to be towards the low end rather them the high end of score of the range
-Produces a positive skew when their are high scores show that it affects the mean which is higher than median creating a positive skew
Examples of a positive skew?
A hard test
most common score was low but a few extreme highs cab show the data
What is a negative skew of data?
The mean is below the median and the mode
Examples of a negative skew of data?
If the marks were plotted for an exam which was very easy to get a high score
However some may get a low score
A way to remember positive and negative skew?
Left foot- negative skew
Right foot- positive skew
Positive skew example?
Look at distribution cure booklet
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Negative skew examples?
Look at distribution cure booklet
