I don’t similar the way my S1 textbook deals alongside skewness. It basically merely sets out methods for identifying skewness without actually explaining what it is. In this postal service I hash out an choice approach.
I usually piece of employment this starter interrogation inwards my get-go S1 lesson of the year:
The indicate beingness that when at that topographic point are outliers inwards a information set, the hateful becomes rather useless (unless of class you lot wishing to deceive people!).
Whilst education S1 I oftentimes uncovering myself referring dorsum to my Bibonacci starter (‘remember that CEO? He ruined the mean!’). So I decided to brand a worksheet out of it - come across below - which I used for the get-go fourth dimension this yr when education skewness (if you lot similar this thence delight acquire out me a review on TES!). My pupils enjoyed the activeness too it generated interesting discussions.
The substitution education indicate is that when information is skewed, the median is to a greater extent than meaningful than the mean. We convey diverse methods for identifying skewness inwards a information ready (summarised inwards these slides – sorry, master copy source unknown) - nosotros usually reckon the shape of a frequency diagram or box plot. Sometimes skewness is apparent merely from looking at the raw information (this sideways stem-and-leaf diagram is interesting).
The substitution education indicate is that when information is skewed, the median is to a greater extent than meaningful than the mean. We convey diverse methods for identifying skewness inwards a information ready (summarised inwards these slides – sorry, master copy source unknown) - nosotros usually reckon the shape of a frequency diagram or box plot. Sometimes skewness is apparent merely from looking at the raw information (this sideways stem-and-leaf diagram is interesting).
Pupils involve to recollect that positive skew way nosotros convey a few 'sparse' information points (possibly outliers) at the top end of the information ready – too similar inwards the Bibonacci example, this volition pull the hateful up. This volition assistance them conceptually empathise the diverse methods described inwards the textbook.
Finally, here's a keen play a trick on that I learnt from my colleague Lizzie... Imagine a cute puppy sitting on the left of the graph. H5N1 positive skew is going to come across the puppy (positive = yay, a puppy!) too a negative skew is going away from the puppy (negative = acquire away from this puppy!). It's a giddy but uncomplicated too memorable way of ensuring that students don't acquire the graphs mixed up.
Finally, here's a keen play a trick on that I learnt from my colleague Lizzie... Imagine a cute puppy sitting on the left of the graph. H5N1 positive skew is going to come across the puppy (positive = yay, a puppy!) too a negative skew is going away from the puppy (negative = acquire away from this puppy!). It's a giddy but uncomplicated too memorable way of ensuring that students don't acquire the graphs mixed up.
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