Question

Collecting data on process outcomes (Y’s) only and not on process variables (X’s):

People who do not know what should be measured: ?

explain with example

Answer 1

Answer:

Process outcome (Y – Dependent Variable): This the process result achieved after the execution of the process with use independent X variables. Thus all the independent X variables are processed to result out Y dependent variable.

Process input (X – Independent variable): These are all the variable required for achieving the Y output from the process. Without the use of applicable X variables, the Y variable cannot be achieved. Thus use of X variable is must and compulsory for achieving the Y variable.

Measurement of Y - Dependent Variable: This means the process analyzer is measuring the process output. The process output measurement will help the analyzer to understand the variation observed in the process output. Thus Y measurement will advise the process output with current set of variation observed in the output.

Measurement of X – Independent Variable: The measurement fo X independent variable will be able to help the causes and reason for variation in the Y result. Thus X- variable measurement is necessary for understanding the variationin Y-variable.

If people do not aware on the importance of X variable and Y variable and their interrelationship for effect of one on another, then their measurement will not be of any use and the exercise will be the waste of time and resources.

Thus if the process analyzer wants to understand the variation in process output (Y Variable), the he needs to measure the process input variable i.e. X variables. Thus the measurement and analysis of X variable will only let the analyzer to understand the variation in the Y variable.

Example:

School bus reaches the school gate late every day. If the bus administrator only measures the arrival time of bus, then he will not be able to understand the reason why the bus is reaching late.

Y Variable = Bus Arrival (process output)

X Variable are as below

• Bus start time = X1
• Traffic in city = X2
• Students boarding = X3
• Bus Maintenance Issues = X4

Thus the administer needs to understand the above stated X variables in order to understand the late arrival of bus at the school. Thus without X variable measurement, the bus administrator cannot understand the variation in the bus arrival tiem to the school.