Mesure Metric Indicatior

7/30/2019 Mesure Metric Indicatior

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First, let's look at the definitions of these terms (the definitions are in italics):

Measure- To ascertain or appraise by comparing to a standard [1]. A standard or unit ofmeasurement; the extent, dimensions, capacity, etc., of anything, especially as determined by a

standard; an act or process of measuring; a result of measurement [3]. A related term isMeasur ement

- The act or process of measuring. A figure, extent, or amount obtained bymeasuring [1]. The act or process of measuring something. Also a result, such as a figure

expressing the extent or value that is obtained by measuring [3].

An example measure might be five centimeters. The centimeter is the standard, and five

identifies how many multiples or fractions of the standard are being appraised. With the

centimeter, someone measuring something in the United States is going to get the same measureas someone in Europe.

Let's relate this to software, such as lines of code. Currently, there really isn't a universalstandard for lines of code. Someone measuring a program's lines of code in one office will

probably not get the same count as someone measuring the same program in a different office.Therefore, it is imperative that each organization determine a single standard for what is meant

by a line of code and ensure that everyone in the organization understands and uses that standard.Thus, a measure may be universally standard or locally standard, but it needs to be a standard.

Metric- A quantitative measure of the degree to which a system, component, or processpossesses a given attribute [2]. A calculated or composite indicator based upon two or more

measures. A quantified measure of the degree to which a system, component, or process

possesses a given attribute [3].

An example of a metric would be that there were only two user-discovered errors in the first 18

months of operation. This provides more meaningful information than a statement that thedelivered system is of top quality.

I ndicator- A device or variable that can be set to a prescribed state based on the results of aprocess or the occurrence of a specified condition. For example, a flag or semaphore [2]. A

metric that provides insight into software development processes and software process

improvement activities concerning goal attainment [3].

As the definition notes, a flag is one example of an indicator. An indicator is something that

draws a person's attention to a particular situation. Another example of an indicator is theactivation of a smoke detector in your home; it is set to a prescribed state and sounds an alarm if

the number of smoke particles in the air exceeds the specified conditions for the state for whichthe detector is set. In software terms, an indicator may be a substantial increase in the number of

defects found in the most recent release of code.

My objective is not to add more definitions or confusion but to give an example to help youunderstand the differences between these terms. A few charts can help clarify the differences.

Let's start with a common scenario that involves a sick patient.


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An individual is brought into a hospital emergency room. He is unconscious and has a

temperature of 99.1 degrees Fahrenheit (see Figure 1). Other vital signs appear normal. What

does the measure of 99.1 degrees Fahrenheit tell you? Very little. You may realize that it isabove normal body temperature, but you don't know if the temperature is going up, down, or

remaining constant. So is this individual getting better or getting worse?

Now, after many hours of regularly checking the patient's vital statistics, we are able to see a

trend in the temperature readings (see Figure 2).

This trend analysis gives the doctors a lot more to work with, even though the patient is still

unconscious. What does the chart in Figure 2 show us? The temperature continues to climb and

even more rapidly as the second day progresses. The doctors start to worry, but other vitalstatistics show no problems.

Suddenly, the patient awakes and provides more information about his condition. He isFprouktquiktzarpkx, from the planet Zorkkokkroz, and his normal body temperature is 105.6

degrees Fahrenheit (see Figure 3). He was recovering from hypothermia.


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The above scenario helps to illustrate the difference between measures, metrics, and indicators.

Figure 1 shows a measure. Without a trend to follow or an expected value to compare against, a

measure gives little or no information. It especially does not provide enough information to makemeaningful decisions.

Figure 2 shows a metric. A metric is a comparison of two or more measures--in this case bodytemperature over time--or defects per thousand source lines of code.

Figure 3 illustrates an indicator. An indicator generally compares a metric with a baseline orexpected result. This allows the decision makers to make a quick comparison that can provide a

perspective as to the "health" of a particular aspect of the project. In this case, being able to

compare the change in body temperature to the normal body temperature makes a big differencein determining what kind of treatment, if any, may be needed.

This example is obviously fictitious (I think). But it does illustrate the point that a little bit ofinformation can be dangerous. This does not mean that no information is better; it means that the

right amount of information of the right kind is needed to make the best decisions. So do we waituntil we have all the information we want before we make decisions? No. But recognize that

without enough of the right information, there is a risk involved in making that decision.

The example also illustrates that our frame of reference is not always the right one. We must bewilling to look at situations with an objective view. If we cannot see a situation from more thanone angle, we may need to request consultation from someone with a different persepective.


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A measure is a value that is quantified against a standard at a point in time. For example, if we

calculate a stores sales for January 2008, the standard is the dollar, and the Total Sales for

Jan 2008 is the measure. A single measure usually has little value without some context. How

do we know if $25,000 in sales for that month is good or bad?

Suppose we track monthly sales over a 13 month period between January 2007 and January

2008. Now, we have some context to see our January 2008 sales trending up or down? A metric

is the degree to which a particular subject possesses the quality that is being measured. It is

based upon two or measures. Total Monthly Sales for 1/07-1/08 is our metric.

In our example, Total Monthly Sales gives us more context and understanding of the

relationship between measures. However, the fact that this stores sales are trending up

may not give us the complete perspective of how this store is performing. However, if we

measure the stores sales against a baseline such as budgeted sales, then we get a truer

indicator of performance. Total Monthly Sales to Budget for 1/07-1/08 is our indicator. If this is


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provides us with actionable information that we use to drive our business, then we would

consider this to be a Key Performance Indicator.

Organizations or individuals may vary some in their use of these terms. It is nevertheless

valuable to consider how we progress from a single measurement to indicators of success.


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Definition:

Measure- To ascertain or appraise by comparing to a standard [1]. A standard or unit ofmeasurement; the extent, dimensions, capacity, etc., of anything, especially as determined by a

standard; an act or process of measuring; a result of measurement [3]. A related term is

Measure: To ascertain or appraise by comparing to a standard . A standard or unit of

measurement; the extent, dimensions, capacity, etc., of anything, especially as determined by a

standard;;A measure is a value that is quantified against a standard at a point in time. For

example, if we calculate a store sales for January 2008, the standard is the dollar, and the Total

Sales for Jan 2008 is the measure. Say the numbers of lines in a software code.A Measure is

generally a single quantitative value or field that is generated at a low level and then summarized

for analysis.

Measur ement- The act or process of measuring. measurement is process of experimentally

obtaining one or more quantity values that can reasonably be attributed to a quantity.

Metric : A quantitative measure of the degree to which a system, component, or process

possesses a given attribute A metric is the degree to which a particular subject possesses the

quality that is being measured. A metric is a comparison of two or more measures. Total

Monthly Sales for 1/07-1/08 is our metric. A software metric is a measure of some property of a

piece of software or its specifications.A calculated or composite indicator based upon two or

more measures. An example of a metric would be that there were only two user-discovered

errors in the first 18 months of operation

Indicator : An indicator is a metric or combination of metrics that provide insight into the

software process, a software project or the product itself. A device or variable that can be set to a

prescribed state based on the results of a process or the occurrence of a specified condition. For

example, a flag or semaphore . A metric that provides insight into software development

processes and software process improvement activities concerning goal attainment . An indicator

generally compares a metric with a baseline or expected result. This allows the decision makers

to make a quick comparison to the desired result expected.
http://en.wikipedia.org/wiki/Softwarehttp://en.wikipedia.org/wiki/Softwarehttp://en.wikipedia.org/wiki/Software


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Software Process and Project Metrices:

Software process and project metrics are quantitative measures They are a management tool They offer insight into the effectiveness of the software process and the projects that are

conducted using the process as a framework

Basic quality and productivity data are collected These data are analyzed, compared against past averages, and assessed The goal is to determine whether quality and productivity improvements have occurred The data can also be used to pinpoint problem areas Remedies can then be developed and the software process can be improved

Software metrics can be classified into three categories: product metrics, process metrics, and project

metrics.

Product metrics describe the characteristics of the product such as size, complexity, design features,

performance, and quality level. Process metrics can be used to improve software development and

maintenance. Examples include the effectiveness of defect removal during development, the pattern of

testing defect arrival, and the response time of the fix process. Project metrics describe the project

characteristics and execution. Examples include the number of software developers, the staffing pattern

over the life cycle of the software, cost, schedule, and productivity.

Process metrics are measures of the software development process, such as Overall development time Type of methodology used

Process metrics are collected across all projects and over long periods of time. Their intent is to provide indicators that lead to long-term software process improvement.


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To improve any process, the rational way is: Measure Specific attributes of the process Derive meaningful metrics from these attributes. Use these metrics to provide indicators. The indicators lead to a strategy for improvement.

How to Measure Effectiveness of a Software Process?

We measure the effectiveness of a software process indirectly We derive a set of metrics based on the outcomes that can be derived from the process. Outcomes include

Errors uncovered before release of the software Defects delivered to and reported by end-users Work products delivered (productivity) Human effort expended Calendar time expended etc. Conformance to schedule

Project Metrics:

Project Metrics are the measures of Software Project and are used to monitor and controlthe project. They enable a software project manager to:

Minimize the development time by making the adjustments necessary to avoiddelays and potential problems and risks.

Assess product quality on an ongoing basis & modify the technical approach toimprove quality.

Used in estimation techniques & other technical work. Metrics collected from past projects are used as a basis from which effort and time

estimates are made for current software project.

As a project proceeds, actual values of human effort & calendar time expended arecompared to the original estimates.


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This data is used by the project manager to monitor & control the project.

Product metrics:

Product metrics are measures of the software product at any stage of its development,from requirements to installed system. Product metrics may measure:

the complexity of the software design the size of the final program the number of pages of documentation produced

Common software metrics include:

order of growth (See Analysis of algorithms in terms of Asymptotic analysis and Big O notation)

source lines of code

cyclomatic complexity

function points

bugs per line of code

code coverage

number of lines of customer requirements.

number of classes and interfaces

Robert Cecil Martin's software package metricsCohesion

Coupling (computer science)

Examples of process metrics affecting software:

Number of times the program failed to rebuild overnight

Number of defects introduced per developer hour

Number of changes to requirements

Hours of programmer time available and spent per week

Number of patch releases required after first product ship

ize-oriented Metrics


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Attempt to quantify software projects by using the size of the project to normalize other quality

measures

Possible data to collect: number of lines of code

number of person-months to complete cost of the project number of pages of documentation number of errors corrected before release number of bugs found post release

Function-Oriented Metrics

Attempt to measure the functionality of a software system

Use a unit of measure called function point Some possible function points: Internal data structures External data structures User inputs User outputs Transformations Transitions

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