mod 7 Flashcards
impact of forecasting on supply chain
allows to better predict demand: better inventory management, production planning, and reducing costs w/o overstocking
best forecasting method
depends on product, planning, costs, resources
Delphi Method vs. Expert Opinions
delphi: multiple forecasts
expert: one time input from an individual
weakness of sales forces opinions and market research
sales force: biased due to personal beliefs and performance targets
Market research: costly and time consuming, and not always accurate due to changes in market
historical life cycle analogy
looks at demand patterns of similar products to predict life cycle of product (good for new products)
plotting past demand data
helps to see trends and seasonal patterns/ fluctuations
responsive v smoothing time series
responsive methods: smaller moving avg window allows for faster adaptation to market conditions
smoothing: using larger moving average clearer long term trend
smoothing
used to reduce flucations in data providing cleaer signal or trend
naive forecasr
if last months demand was x then this months forecast is x
smoothing in moving average forecast (n of 3 v 5)
n of 5 more smoothing then n of 3 (avg over longer period)
smoothing in exponential forecast
a=.1 and a=.5
a=.1 offers more then a=.5 (lower values gives more weight)
linear trend v linear regression
linear trend: for time series data (predicting future values based on past trends)
linear regression: used to find relationship between independent and dependent variables
correlation in regression output
correlation coefficient shows strength and direction of linear relationship
coefficient of determination in regression output
r^2 value shows variation
MSE vs MAD
MSE (mean squared error) preferred when larger errors are penalized
MAD (mean absolute deviation) less sensitive to larger outliers