Statistical Techniques Flashcards
What is the average annual change formula?
Last years figure - first years figure / number of years - 1
What is an individual and dependant variable?
The measurement which is at a fixed individual
The figure which is dependant on the independent variable
Whats the formula which is able to replicate a trend?
Y = mx + c
Y is the forecast amount
M is the trend which it increases or decreases by
X number of years since the start
C figure at the start year
What are moving averages?
Term used for a series of averages calculated from a stream of data, each subsequent average moves along by one
eg: 1st average will be based off - 1, 2, 3
2nd average will be based off - 2, 4, 5
What is the formula for seasonal variations?
Actual/Sales = Trend +/- Seasonal Variations
What are the four main factors which can influence data generated over a period of time?
The underlying trend - trend generally moving in one direction over a long period of time
Long-term cycles - Slow moving variations caused by social trends and economic cycles
Seasonal variations
Random Variations
What does the term ‘extrapolate’ mean?
Forecasting how the trend will move in the future.
What are some topics which you should comment on when answering a profitability question?
Most likely weighted profit for each product
Consider grouping probabilities together
Profit range for each product
What is time series analysis?
Examination of historical data that occurs over time, with the intention of forecasting the future
What is linear regression?
Using a formula to demonstrate the movement of data over time, helps forecast movement of trends.
What is the formula for creating Index Numbers?
New / Old x 100
What is the formula for converting using index numbers?
Index or RPI in base / Index or RPI new year x value for year in question.
