Kiwi Fruit Harvest

Waihi College Kiwi Fruit Harvest

The school's orchard is nearly ready for harvesting.  The school has 3 hectares of commercial crop of kiwi fruit.

Kiwifruit is produced for two main markets - export (these are finest grade kiwifruit) and the local supermarkets (these are the over/under sized or unusually shaped or marked kiwifruit).

Today we're going to measure out our sample from the orchard.

I want you to have the length width height (all to nearest cm) and weight (nearest gm) measured.

We'll have a database formed for recording this information.

This we'll use to do some statistics and graphs in our investigation.

We will be looking to see if there is a relationship between the height and the weight of kiwifruit here at Waihi College.

PPDAC

Plan - how can we gather a 'fair' sample of fruit?  What are we measuring and how are we measuring it?  What units are we going to use?  Are we rounding or making any judgement calls (e.g. a fruit with a hole in it?  The measuring is evidence for the portfolio on measurement.  

Data - we will record this on a spread sheet in class.

Analysis - we will use a scatterplot to show our data.  We will make statements about what we see.

Conclusion - there maybe a relationship (maybe not).  If there is - is that relationship positive/negative, strong?  Can we make a logic statement about what happens with length and weight?

The First Graphs

First Up Graphs

The two most common graphs (these are acceptable for the numeracy standard 26626) are back to back stem and leaf graphs.  These show the numbers/data for two categories.

The trick here is to know how to read the numbers,  Can you see where the before number is 82 beats per min?

The benefits of the back to back stem and leaf graph is that you can easily see the spread of the data and make an quick comment.  "the pulse rates are generally lower (smaller numbers) in the before category.

You can also quickly find the highest, lowest, median numbers (and the quartiles).







The second most important graph to do is our dot plot graph.  These look like.

Contexts

Getting the Context Right

You need to have for this numeracy unit standard (26627) is a real context.  E.g. We can't just hand in a page on mobile phone prices - unless this has a real context.

E.g. the school ball in July is coming up for you guys - this is a real context that we can do some statistics on.

When you are doing your work you have to include a decent descriptor of the context.  Why is it real for you to be working on?


We begin our statistical investigations with a common question.  This needs to have the right wording...

"I wonder if boys spend less on mobile phones than girls at Waihi College in year 11"  The bits underlined are complusory - the I wonder if and the specific context of where the data comes from.  

Example of What To Hand In...

Here is the best type of template you can use to hand in. 

It is important that you do this as you have to have a real world reason for doing what you're doing.  



_____________________________________________________________________

Name                              Activity Heading                                              26626


Context.   - (here you write up what it is that you are investigating and why we are doing this).  


Evidence of Data.   - (here you can show what data you have used to generate your statistics and/or graphs).  Most likely this will be a list of about 30+ numbers.  


Statistics.  - (you will have to show mean/median/mode/range... perhaps quartiles and interquartile range).  


Graph(s).  - (you will most likely have a graph or two).   These need to be really well done - no errors).  


Observations.  - (what do your eyes tell you about what you have investigated?).  State the obvious.  Trend and Unusual Features are key.  


Conclusions.  - vital!  (what has all this taught you.  What do the results say?  can you back it up with the graph or statistics).  

26626 Intro To Statistics

Numeracy Statistics

The final of our three 'numeracy' standards this year is on Statistics (the study of lots of numbers).

Here is a copy of the actual standard (click here).

Here is what the evidence collection will look like...