Class notes
A-Level further maths notes on statistic and hypothesis testing OCR MEI
- Course
- Institution
Notes with detailed explanations for 1st year further maths statistics, Goodness of fit and PMCC. Contains examples
[Show more]
Seller
Follow
2poppc68
Content preview
PMCC Hypothesis Testing - RevisionDependant and independent variables
Independent variables:
The number of goals scored by a premier league football team in a season
The amount of rain falling on a field
The number of people visiting a bar
Dependent variables:
The number of points a team has in the league table
The weight of a crop yielded while the crop is growing
The volume of beer sold in an evening
Controlled Variables
Sometimes, one or both of the variables are controlled, so that the variable only
assumes a set of predetermined values; for example, the times at which
temperature measurements are taken at a meteorological station. Controlled
variables are non-random. Situations in which the independent variable is
controlled and the dependent variable is random form the basis of regression
analysis.
Mean formula
Product moment correlation
, Where there is a positive correlation most or all of the data points will fall in
Regions 1 and 3 and so you would expect the sum of these products to be positive
and large.
Where there is a negative correlation as in the case shown in the text book (page
81), most or all of the points will be in Regions 2 and 4 an d so you would expect
the sum of these products to be negative and large.
Where there is little or no correlation, the points will be scattered around all four
regions. Those in Regions 1 and 3 will result in positive values or (x, - x)(y, - y) but
when you add these to the negative values from the points in Regions 2 and 4 you
would expect most of them to cancel each other out. Consequently, the total value
of all the terms should be small.
The sum of terms is denoted by:
By itself this does not tell you very much because:
No allowance has been made for the number of items of data
No allowance has been made for the spread within the data
No allowance has been made for the units of x and y
Pearson's Product Moment Correlation Coefficient
To allow for both the number of items and the spread within the data, together
with the units of x and y, the value of Sxy is divided by the square root of the
product of Sxx and Syy.
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller 2poppc68. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $8.38. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
53068 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now