STA630 Online Quiz No. 1 Fall 2011 Announcement

Online Quiz # 01

All Students of Fall Semester 2011 are informed that Online Quiz # 01 for

“Research Methods (STA630)” will be uploaded according to the following schedule:

Opening Date and Time : October 31, 2011 At 12:01 AM

Closing Date and Time : November 01, 2011 At 11:59 PM

STA630 Assignment No. 2 solution

Research Methods (STA630)

Assignment No. 2

Marks: 20

No.7

“No. 7” is a Pakistani denim manufacturer company dealing in colored fabric. For last three years, sales of “No. 7” have been declining significantly. The reason, shown by sales data, was its color scheme. Two types of color schemes were being used. In first type, light colors were contrasted with dark ones; while in other, block dark colors were used. It was found that the sale of dark block colors was declining hence affecting the overall sales; however the combination of dark and light was in demand.

There are a number of factors which can affect the customers’ color choices. In order to further explore the issue and to make the appropriate strategy, a team of researchers was assigned the task to identify the factors affecting the color choice.

You, as a part of research team, are required to:

• Identify the broad problem area (4 marks)

• Identify the problem (4 marks)

• Write Problem statement (4 marks)

• Identify the possible factors affecting the color choice (at least 3) (4 marks)

• Formulate the hypotheses on the basis of identified factors (4 marks)

Solution:

QUESTION # 1
Identify the broad problem area (4 marks)


Color scheme


QUESTION # 2
Identify the problem (4 marks)


Sale of dark block colors was declining



QUESTION # 3
Write Problem statement (4 marks)


We want all of our products releases to go to production seamlessly, without defects, where everyone is aware and informed of the outcomes and status. (Vision)


Today we have color scheme failures that result in dark color blocks failures. If we ignore this problem; resources will need to increase to handle the cascading problems, and we may miss critical customer deadlines which could result in lost revenue, NO 7, lost business, and further damage to our quality reputation. (Issue Statement)


We will use our best efforts in evaluating the last release to help us improve our processes. (Method)



QUESTION # 4
Identify the possible factors affecting the color choice (at least 3) (4 marks)
1.Sagging Economy
2.Poor Sales Forecasting
3.Poor Individual Performance
4.Ineffective Sales Pipeline



QUESTION # 5
Formulate the hypotheses on the basis of identified factors (4 marks)


Four steps for formulating a hypothesis:-


> Define the problem statement
For last three years, sales of No. 7 have been declining significantly. The reason, shown by sales data, was its color scheme


> Determine the solution of the problem statement
The sale is effecting by the DARK color combination as quality of the colors are same but the taste of the customer has been changed. So company will take care of her valued customers and choice i.e. Grow the production of Medium Shades


> Write the proof
Combination of Dark and light colors was in demand so under this considerations company will prefer the choice of customers.


> Methods for checking the proof


By conducting several surveys
1. Face to face talk
2. Telephonic talk
3. Suggestions by mail etc
By checking the sales
By checking the increasing demand of the customers

STA301 Assignment No. 4 Announced

Assignment No.4 (Course STA301)

Fall 2010 (Total Marks 30)

Deadline

Your Assignment must be uploaded/ submitted before or on 23:59 Feb 03, 2011

(STUDENTS ARE STRICTLY DIRECTED TO SUBMIT THEIR ASSIGNMENT BEFORE OR BY DUE DATE. NO ASSIGNMNENT AFTER DUE DATE WILL BE ACCEPTED VIA E.MAIL).

Rules for Marking

It should be clear that your Assignment will not get any credit IF:

The Assignment submitted, via email, after due date.

The submitted Assignment is not found as MS Word document file.

There will be unnecessary, extra or irrelevant material.

The Statistical notations/symbols are not well-written i.e., without using MathType software.

The Assignment will be copied from handouts, internet or from any other student’s file. Copied material (from handouts, any book or by any website) will be awarded ZERO MARKS. It is PLAGIARISM and an Academic Crime.

The medium of the course is English. Assignment in Urdu or Roman languages will not be accepted.

Assignment means Comprehensive yet precise accurate details about the given topic quoting different sources (books/articles/websites etc.). Do not rely only on handouts. You can take data/information from different authentic sources (like books, magazines, website etc) BUT express/organize all the collected material in YOUR OWN WORDS. Only then you will get good marks.

Objective(s) of this Assignment:

The assignment is being uploaded to build up the concepts about sampling techniques and testing of hypothesis. Application of the hypothesis testing and confidence interval.

How to get sample size from the given information.

Concepts about unbiasedness and precision

Assignment # 4 (Lessons 31-40)

Question 1: (Marks: 5x1=5)

Give the answer of short questions.

a) When we use central limit theorem?

b) What is the technique to find the estimates of an infinite population?

c) , what do you say about the estimator T, where is a parameter?

d) How precision of an interval estimate can be increased?

e) If an 85% confidence interval is 27.5< <43.8,>

Question 2: (Marks: 6+4=10)

a) In an finite population with and , find the mean and variance for the sampling distribution of if:

b) Find the value of sample size in case of proportions.

Question 3: (Marks: 5+5+5=15)

Test the hypothesis

The masses, in grams, of thirteen ball bearings seen at random from a batch are

21.4, 23.1, 25.9, 24.7, 23.4, 24.5, 25.0, 22.5, 26.9, 26.4, 25.8, 23.2, 21.9

Calculate a 95% confidence interval for the mean mass of the population.

If n=36, s=9 and t=2, what is the values of?

STA630 GDB No. 2 solution

GDB 2

Dated:

Jan 21, 11

Semester Fall 2010

“Research Methods (STA630)”

This is to inform that Graded Discussion Board (GDB)

will be opened according to the following schedule

Schedule

Opening Date and Time

January,24, 2011 At 12:01 A.M. (Mid-Night)

Closing Date and Time

January,26, 2011 At 11:59 P.M. (Mid-Night)

Topic/Area for Discussion

“DATA ANALYSIS”

Note: The discussion question will be from the area/topic mentioned above. So start learning about the topic now.

......

Question/Description

"Briefly describe the situation where Coding of the responses can be done before the data collection and when coding is done after the data collection? "

Solution:

Briefly describe the situation where Coding of the responses can be done before the data collection and when coding is done after the data collection?

Coding before the collection of data:

Whenever is possible the best way of processing is to begin before the actual survey is carried out. Pre-coding is a procedure that applies to only close ended questions where answers are few in numbers and predictable. This can be done when questions are highly structured and only can have a few answers. It involves two operations, (1) attaching a numerical value to each response, (2) designing a location for every item in the questionnaire.

Coding after the collection of data:

When questions are open ended and answers are not predictable the coding of data is done after the data is actually collected. Categories in which responses are to be coded must be established after examining that what respondent actually had to say?

In many cases, such as when researchers are using open-ended questions, a framework for classifying responses to questions cannot be established before data collection. This situation requires some careful thought concerning the determination of categories after editing process has been completed. This is called post-coding or simply coding.

STA301 GDB Solution

GMDB Dated: Jan 10, 11

Dear Students,

Graded MDB for STA301 will be opened on Jan 17, 2011 and will remain open till Jan 19, 2011. The topic of this GMDB will be.

“Suppose you read a published statement that the average amount of food consumption in this country is adequate; the overall conclusion based upon the statement is that everyone is properly fed. Criticize the conclusion in terms of the concept of variability as it relates to the use of averages.”.

Post your comments after inferring the above topic. Your comments should NOT exceed from 80-100 words. NOTE: Your comments MUST be posted with in due date and it will NEVER accept through e-mail.

Solution:

After World War 1 Germany experienced one of the history’s most speculator example of hyperinflation. The German government did not pay for the war by taxing people more heavily. Things got worse at the end of the war. A huge amount for damages (reimbursement) was demanded from Germany. The sum to be paid was fixed at £6,600,000 in 1921. Germany’s currency loses confidence of many foreigners because Germany was unable to pay for damages. German government has to face budget deficit because value of their currency decreased too much and they have to pay more in exchange for other currencies.

STA630 GDB No. 1 Solution

Semester Fall 2010

"Research Methods (STA630)"

Schedule

Opening Date and Time

November 22, 2010 At 12:01 A.M. (Mid-Night)

Closing Date and Time

November 24 , 2010 At 11:59 P.M. (Mid-Night)

Topic/Area for Discussion

"MEASUREMENT OF CONCEPTS"

Note: The discussion question will be from the area/topic mentioned above. So start learning about the topic now.

....................

Discussion Question

"Which of the scale among ratio and interval scale is better? Justify our answer"

..........

Solution:

I think Ration Scale is better:

Interval Scale:-Permissible Statistics

mean, standard deviation, correlation, regression, analysis of variance

Ratio Scale:-Permissible Statistics
All statistics permitted for interval scales plus the following: geometric mean, harmonic mean, coefficient of variation, logarithms

Interval scale

Quantitative attributes are all measurable on interval scales, as any difference between the levels of an attribute can be multiplied by any real number to exceed or equal another difference. A highly familiar example of interval scale measurement is temperature with the Celsius scale. In this particular scale, the unit of measurement is 1/100 of the difference between the melting temperature and the boiling temperature of water at atmospheric pressure. The "zero point" on an interval scale is arbitrary; and negative values can be used. The formal mathematical term is an affine space (in this case an affine line). Variables measured at the interval level are called "interval variables" or sometimes "scaled variables" as they have units of measurement.

Ratios between numbers on the scale are not meaningful, so operations such as multiplication and division cannot be carried out directly. But ratios of differences can be expressed; for example, one difference can be twice another.

The central tendency of a variable measured at the interval level can be represented by its mode, its median, or its arithmetic mean. Statistical dispersion can be measured in most of the usual ways, which just involved differences or averaging, such as range, interquartile range, and standard deviation. Since one cannot divide, one cannot define measures that require a ratio, such as studentized range or coefficient of variation. More subtly, while one can define moments about the origin, only central moments are useful, since the choice of origin is arbitrary and not meaningful. One can define standardized moments, since ratios of differences are meaningful, but one cannot define coefficient of variation, since the mean is a moment about the origin, unlike the standard deviation, which is (the square root of) a central moment.

Ratio measurement

Most measurement in the physical sciences and engineering is done on ratio scales. Mass, length, time, plane angle, energy and electric charge are examples of physical measures that are ratio scales. The scale type takes its name from the fact that measurement is the estimation of the ratio between a magnitude of a continuous quantity and a unit magnitude of the same kind (Michell, 1997, 1999). Informally, the distinguishing feature of a ratio scale is the possession of a non-arbitrary zero value. For example, the Kelvin temperature scale has a non-arbitrary zero point of absolute zero, which is denoted 0K and is equal to -273.15 degrees Celsius. This zero point is non arbitrary as the particles that compose matter at this temperature have zero kinetic energy.

Examples of ratio scale measurement in the behavioral sciences are all but non-existent. Luce (2000) argues that an example of ratio scale measurement in psychology can be found in rank and sign dependent expected utility theory.

All statistical measures can be used for a variable measured at the ratio level, as all necessary mathematical operations are defined. The central tendency of a variable measured at the ratio level can be represented by, in addition to its mode, its median, or its arithmetic mean, also its geometric mean or harmonic mean. In addition to the measures of statistical dispersion defined for interval variables, such as range and standard deviation, for ratio variables one can also define measures that require a ratio, such as studentized range or coefficient of variation.

Interval Scale

An interval scale assumes that the measurements are made in equal units. However, an interval scale does not have to have a true zero. Good examples of interval scales are the Fahrenheit and Celsius temperature scales. A temperature of "zero" does not mean that there is no temperature...it is just an arbitrary zero point. An Interval Scale

Ratio Scale

Ratio scales are similar to interval scales. A ratio scale allows you to compare differences between numbers. For example, if you measured the time it takes 3 people to run a race, their times may be 10 seconds (Racer A), 15 seconds (Racer B) and 20 seconds (Racer C). You can say with accuracy, that it took Racer C twice as long as Racer A. Unlike the interval scale, the ratio scale has a true zero value.

INTERVAL SCALE

A characteristic of data such that the difference between two values measured on the scale has the same substantive meaning/significance irrespective of the common level of the two values being compared. This implies that scores may meaningfully be added or subtracted and that the mean is a representative measure of central tendency. Such data are common in the domain of physical sciences or engineering - e.g. lengths or weights. Also see : MEASUREMENT TYPE, SCALE TYPES, STEVENS' TYPOLOGY.

RATIO SCALE

This is a type of MEASUREMENT SCALE for which it is meaningful to reason in terms of differences in scores (see INTERVAL SCALE) and also in terms of ratios of scores. Such a scale will have a zero point which is meaningful in the sense that it indicates complete absence of the property which the scale measures. The RATIO SCALE may be either unipolar (negative values not meaningful) or bipolar (both positive and negative values meaningful), and either continuous or discrete.

STA630 Assignment No.1 solution-2

Effective managers always make sound and effective decisions on the basis of scientific research. Scientific research focuses on solving problems in a step by step, logical and organized manner (i.e. Identifying problem, Gathering data, analyzing it & drawing a conclusion). Scientific research conducted in a proper manner always produces repeatable and comparable research findings. Hallmarks of scientific research are as follows:

• Purposiveness
• Rigor
• Testability
• Replicability
• Precision and confidence
• Objectivity
• Generalizibility
• Parsimony

As for the given case, the research has a clear purpose (i.e. to pinpoint the problem / internal issues that are affecting the customer base).

The researchers and consultants carried out the research in a Rigorous manner (i.e. the researchers developed a theoretical base & collected relevant detailed information from a carefully picked sample of 25 employees and 100 customers).

The research mentioned in the case is Replicable and generalizable to other similar situation in same / different organizations.

The management of the company is confident to have 90% precision (which is very close to accuracy) in the research.

The research is being conducted by and independent consultants firm. Furthermore, the researches (employees and customers) are being conducted parallel to each other by independent researchers, which eliminates / reduces the chances of biasness to the minimum level.

The research is conducted in a parsimonious manner.

..............

Another:

This is not the solution you have to write points according to given case.

The Hallmarks of Scientific Research

PURPOSIVENESS:

: SHOULD HAVE DEFINITE AIM

It has to start with a definite aim or purpose.

The focus is on increasing employee commitment.

Increase employee commitment will translate into less turnover, less absenteeism and increased performance levels.

Thus it has a purposive focus.

REFLECT RIGOR

REFLECT RIGOR: SHOW CAREFULNESS, SCRUPULOUSNESS & DEGREE OF

EXACTITUDE IN RESEARCH INVESTIGATIONS

A good theoretical base and sound methodological design would add rigor to the purposive study.

Rigor adds carefulness, scrupulousness and the degree of exactitude in research.

Example:

A manager asks 10-12 employees how to increase the level of commitment. If solely on the basis of their responses the manager reaches several conclusions on how employee commitment can be increases, the whole approach to the investigation would be unscientific. It would lack rigor for the following reasons

TESTABILITY

TESTABILITY: CAN BE TESTED BY APPLICATION OF CERTAIN STATISTICAL

TESTS TO COLLECTED DATA

After random selection manager and researcher develops certain hypothesis on how manager employee commitment can be enhanced, then these can be tested by applying certain statistical tests to the data collected for the purpose.

REPLICABILITY

REPLICABILITY: SHOULD PROVIDE SAME RESULTS IF TESTS ARE

REPEATED IN OTHER SIMILAR CIRCUMSTANCES

It means that it can be used again if similar circumstances prevail.

Example:

The study concludes that participation in decision making is one of the most important factors that influences the commitment, we will place more faith and credence in these finding and apply in similar situations. To the extent that this does happen, we will gain confidence in the scientific nature of our research

PRECISION AND

PRECISION AND CONFIDENCE: HAVE ACCEPTABLE DEGREE OF

ACCURACY AND PROBABILITY OF APPLICATION TO THE WHOLE

Precision refers to the closeness of the findings to "reality" based on a sample.

It reflects the degree of accuracy and exactitude of the results of the sample.

Example: If a supervisor estimated the number of production days lost during the year due to absenteeism at between 30 and 40, as against the actual of 35, the precision of my estimation more favorably than if he has indicated that the loss of production days was somewhere between 20 and 50.

OBJECTIVITY

OBJECTIVITY: BASED ON FACTS AND NOT ON SUBJECTIVE OR EMOTIONAL

VALUES

The conclusions drawn through the interpretation of the results of data analysis should be objective; that is, they should be based on the facts of the findings derived from actual data, and not on our subjective or emotional values.

Example: If we had a hypothesis that stated that greater participation in decision making will increase organizational commitment and this was not supported by the results, it makes no sense if the researcher continues to argue that increased opportunities for employee participation would still help

GENERALIZABILITY

GENERALIZABILITY: HAVE SCOPE OF APPLICATION TO OTHER SETTINGS

It refers to the scope of applicability of the research findings in one organization setting to other settings.

Example: If a researcher's findings that participation in decision making enhances organizational commitment are found to be true in a variety of manufacturing, industrial and service organizations, and not merely in the particular organization studied by the researcher, then the generalizability of the findings to other organizational settings in enhanced. The more generalizable the research, the greater its usefulness and value.

PARSIMONY

PARSIMONY: SIMPLICITY IN EXPLAINING THE PHENOMENA THAT OCCUR

AND IN GENERATING SOLUTIONS FOR THE PROBLEMS

Simplicity in explaining the phenomenon or problems that occur, and in generating solutions for the problems, is always preferred to complex research frameworks that consider an unmanageable number of factors.

...............................

Effective managers always make sound and effective decisions on the basis of scientific research. Scientific research focuses on solving problems in a step by step, logical and organized manner (i.e. Identifying problem, Gathering data, analyzing it & drawing a conclusion). Scientific research conducted in a proper manner always produces repeatable and comparable research findings. Hallmarks of scientific research are as follows:
• Purposiveness
• Rigor
• Testability
• Replicability
• Precision and confidence
• Objectivity
• Generalizibility
• Parsimony

As for the given case, the research has a clear purpose (i.e. to pinpoint the problem / internal issues that are affecting the customer base).

The researchers and consultants carried out the research in a Rigorous manner (i.e. the researchers developed a theoretical base & collected relevant detailed information from a carefully picked sample of 25 employees and 100 customers).

The research mentioned in the case is Replicable and generalizable to other similar situation in same / different organizations.

The management of the company is confident to have 90% precision (which is very close to accuracy) in the research.

The research is being conducted by and independent consultants firm. Furthermore, the researches (employees and customers) are being conducted parallel to each other by independent researchers, which eliminates / reduces the chances of biasness to the minimum level.

The research is conducted in a parsimonious manner.

........................

The company having a large a large number of customers and was going in success. Now the company is in loss and not generating profit this is very alarming situation for management and directors.
In this way they the researcher will collect data through different employees and make a conclusion of the problem external or internal causing loss for the company.
In this case according to hallmark of scientific method they should act upon following research method to reach the problem.

1) Observation of the situation

2) identifying the problem.

3) Formulating a theory.

4) Generate a hypothesis.

5) Analyzing the data collection or hypothesis.

6) Result or conclusion of the research process.