Peramalan Permintaan Part 1 (Moving Average and Weighted Moving Average)

Summary

This video tutorial provides an introduction to forecasting demand and production in operations management. The presenter explains two key forecasting methods: the Moving Average and the Weighted Moving Average. The Moving Average method involves calculating the average of previous data points, while the Weighted Moving Average gives different weights to each data point based on importance. Through detailed examples and practice exercises, the video helps viewers understand how to apply these methods to predict demand and make informed decisions for future production. The session also covers calculations for total costs and profit estimation.

Takeaways

• 😀 Moving Average is a forecasting method used to predict demand or production based on past data over a specific number of periods.
• 😀 In the Moving Average method, the forecast for a future period is calculated by averaging data from previous years, e.g., using 3 years of data to forecast the next year.
• 😀 The Moving Average formula involves adding up the relevant data points and dividing by the number of periods (e.g., 3 years).
• 😀 A practical example is provided where Richard Corporation's sales data is used to calculate the forecast for 2015 using a 3-year moving average.
• 😀 The Weighted Moving Average method assigns different weights to different years, giving more importance to more recent years in the forecast calculation.
• 😀 In the Weighted Moving Average method, each year’s data is multiplied by a specific weight, then summed and divided by the total of the weights.
• 😀 The example for Weighted Moving Average uses sales data and costs, where the weight is given to data based on its relevance, such as 2:4:5:7 for 4 years of data.
• 😀 Total cost calculations are done by summing fixed costs and variable costs, where variable costs are adjusted based on sales data.
• 😀 For the Weighted Moving Average, the calculated cost is used to predict financial outcomes, such as the company’s profit or loss in 2015.
• 😀 Both methods emphasize using past data to predict future demand or costs, making them valuable tools for operational management forecasting.
• 😀 The speaker encourages the audience to practice solving similar problems and apply these methods to other cases for better understanding.

Q & A

What is the moving average method in demand forecasting?

The moving average method is used to forecast demand by calculating the average of sales data from previous periods. It smoothens fluctuations and helps predict future demand by using historical data from a set number of periods.

How is the forecast for 2015 calculated using the moving average method?

To forecast the demand for 2015 using the moving average method, the sales data from the previous three years (2008, 2009, and 2010) is averaged. The calculation results in a forecast of 49,166.67 units for 2015.

What is the formula used in the moving average method?

The formula for the moving average method is: Forecasted demand for the next year = (Sum of data for previous periods) / n, where 'n' is the number of periods (years) used in the calculation.

What distinguishes the weighted moving average method from the regular moving average method?

The weighted moving average method differs from the regular moving average by assigning different weights to the data from different periods. More recent data usually gets higher weights, reflecting its greater importance in forecasting future demand.

How do you calculate the forecast using the weighted moving average method?

To calculate the forecast using the weighted moving average method, multiply the data from each period by its corresponding weight, sum those values, and then divide by the total sum of the weights. This allows more recent data to have a larger influence on the forecast.

In the weighted moving average method, how are the weights assigned?

In the weighted moving average method, weights are assigned based on the importance of each period's data. For example, in a scenario with four years of data, weights might be assigned as 2:4:5:7, with the most recent year receiving the highest weight.

What was the forecasted cost for 2015 using the weighted moving average method?

Using the weighted moving average method, the forecasted cost for 2015 was calculated to be 90,168.33 units.

What is the total cost formula used in the video, and how is it calculated?

The total cost formula is: Total cost = Fixed cost + (Variable cost per unit × Number of units sold). The variable costs are multiplied by the units sold, and the fixed costs are added to calculate the total cost.

How do you determine the profitability of the company based on the forecasted costs?

To determine profitability, subtract the total forecasted costs from the forecasted revenue. If the result is positive, the company is profitable; if negative, the company is incurring a loss.

What was the calculated profit or loss for the company in 2015 based on the forecast?

The company achieved a profit of 400,831.6 rupiah in 2015 after subtracting the total costs from the forecasted revenue of 2,500,000 dollars.