t.test(WingA,WingB, var.equal = TRUE, alternative = "greater"), alternative hypothesis: true difference in means is greater than 0, t = 5.1615, df = 37.957, p-value = 8.031e-06, alternative hypothesis: true difference in means is not equal to 0, To test the effectiveness of the scheme, Titan has taken a random sample of 30 salespeople measured their output in the penultimate month before changeover and then measured it in the fourth month after the changeover (they have deliberately chosen months not too close to the changeover). This belongs to the Confirmatory Data Analysis, as to confirm or otherwise the hypothesis developed in the earlier Exploratory Data Analysis stage. Even if the population is not following the Normal Distribution but for a large sample (n = large), the sampling distribution of x̄ will approach to (approximated by) normal distribution with mean µx̄ = µ and standard error σx̄ = σ/√n, as per the Central Limit Theorem. R&R Case Solution. It is a symmetric distribution (bell shaped distribution). With a strong presence across the globe, we have empowered 10,000+ learners from over 50 countries in achieving positive outcomes for their careers. So they are estimated by sample standard deviations (s1 and s2) from the respective two samples. H0 should be retained. Hypothesis Testing in R- Introduction Examples and Case Study. The test statistic will follow Student’s t distribution with degrees of freedom (rounding down to nearest integers): As discussed in the aforementioned two cases, it is important to figure out whether the two population variances are equal or otherwise. Each sample may provide a value of sample statistic, so there will be a distribution of sample statistic value from all the possible samples i.e. Alternatively, the sample statistic is a random variable, being a function of sample values (which are random variables themselves). Here, we consider a random variable: di = xi – yi. Here, test statistic value (from the sample) is t = -2.376 and the corresponding p-value (2 tailed) = 0.021 <0.05. Knowing about the population-values on the basis of data from the sample. (Source: The 2014 Digital Marketer, available at ex.pn/1kXJifX.) It is assumed that you are familiar will all of the commands discussed throughout this tutorial. the output, it is an example of the one-tailed t-test. Click to read. Higher the standard error, higher is the variation among different possible values of statistics. So, it may be mentioned that the level of significance (α) is the maximum threshold for p-value. It may be further explained as the probability of observing the test statistic if H0 is true i.e. 1-Description of Industry Analysis:-The furniture industry was highly competitive. Life Insurance companies typically measure the monthly output of a salesperson as the total sum assured for the policies sold by that person during the month. implying the success of sales interventions). Problem 2Suppose it has been calculated that for Titan to break even, the average output must increase by £5000. This approach (paired samples) enables us to compare two populations after controlling the extraneous effect on them. Alternative Hypothesis (H1): The hypothesis opposite/complementary to the Null Hypothesis. So, the effectiveness (success) of the sales promotion interventions is doubtful i.e. Here are just a few examples of how Solutions for HR has helped. Case Study The HRM case study with a solution which focuses on the importance of communication in the organization. (b). As per the following output table (Paired Samples Test), sample mean of differences d̅ = -0.417 with standard deviation of differences sd = 8.011 and value of t statistic = -0.403. The value of the population parameter (population mean) to be tested be µ0 (Hypothesised Value). R&R Introduction of Case Study Bob Reiss in 1983 observed with interest the success in the Canadian market of new game board called “Trivial Pursuit”, The sale of the game in the US tended to be approximately ten times those of sales in Canada since “Trivial Pursuit” had sold 100,000 copies.Now Reiss thought game make a boom in US market and this make a profitable opportunity for him. Hypothesis Testing using Standardized Scale: Here, instead of measuring sample statistic (variable) in the original unit, standardised value is taken (better known as test statistic). (The critical regions are shown as shaded portions in the figure). Two-tailed test could have been used if it was asked “new scheme has significantly, Mean of amount assured before the introduction of scheme = 68450, Mean of amount assured after the introduction of scheme = 72000, Difference in mean = 72000 – 68450 = 3550, μ1 = Average sums assured by salesperson BEFORE changeover. it didn’t result in significant increase in sales, provided all other extraneous factors remain the same. What is the p-value of the hypothesis test if we test for a difference of $5000?Solution:Let  μ2 = Average sums assured by salesperson AFTER changeover.μ1 = Average sums assured by salesperson BEFORE changeover.μd = μ2 – μ1   H0: μd ≤ 5000 HA: μd > 5000This is a right tail test. prepared by Lily Hung Jimmy Hu Andrea Tsai Vincent Yu Megan Lu Bruce Lin Howard Hsieh Risks & Rewards Conclusion - Low Entry Barrier - Short Life Circle - Replicability Strategy - Seasonal Vision - Warehousing & Storage This is a common problem in business decision-making because of lack of complete information and uncertainty but by using sample information, the estimate will be based on the concept of data based decision making. To test the validity of this statement, you select a sample of 30 friends and family. It has settled down after fluctuations in the first two months due to the changeover. Rent the Runway is a Harvard Business (HBR) Case Study on Innovation & Entrepreneurship , Fern Fort University provides HBR case study assignment help for just $11. Suppose from a sample, we get a value of sample mean x̄=73. With α = 0.05 and df = 29, critical value for t statistic (or t_critical ) will be   1.699127. The client identified that substantial cost savings were necessary in order to reduce financial deficits. Download PDF. Paired t-Test (Testing Difference between Means with Dependent Samples): We continue with the example of Ventura Sales, and want to compare the average first quarter sales with the second quarter sales. Since these two are probabilistic events, so we measure them using probabilities: α = Probability of committing Type I error = P [Reject H0 / H0 is true]. So, the Hypotheses: Descriptive table showing the sample size n = 60, sample mean x̄=72.02, sample sd s=9.724. (σ) by sample s.d. R & R Case Case Solution,R & R Case Case Analysis, R & R Case Case Study Solution, Critical Analytical Task/Results The first step that is necessary to analyze the critical issues required in the evaluation of a business atmosphere of Search Paper on caseforest database. What conclusion does the test lead to? So the issue is not the difference but actually the magnitude of difference. what are the chances in support of occurrence of H0. Ta. The new scheme has NOT significantly raised outputs. Thera bank case study using r solutions. If this figure is an alternative hypothesis, what is:(a)  The probability of a type 1 error? If we minimize one, the other will increase and vice versa. As we have observed, paired t-test is actually one sample test since two samples got converted into one sample of differences. Major HBR cases concerns on a whole industry, a whole organization or some part of organization; profitable or … Normally α is fixed and we try to minimise β. (The critical region is shown as a shaded portion in the figure). (a) Population Standard Deviations are unknown but equal: In this situation (where σ1 and σ2 are unknown but assumed to be equal), sampling distribution of the statistic (x̄1 – x̄2) will follow Student’s t distribution with mean µx̄ = µ1– µ2 and standard error σx̄ = √ Sp2(1/ n1 + 1/ n2). So, the Hypotheses: H0: µ1– µ2= 0 or µ1= µ2  (Where, µ1= Population Mean Sale of Urban Outlets and µ2 = Population Mean Sale of Rural Outlets). characteristics of the sample. The size (probability/area) of a critical region is taken as α. frequency distribution of sample statistic. R&R Case Solution, Outlines alternative mechanisms for getting into business. μ2 = Average sums assured by salesperson. Sampling distribution of sample proportion p =x/n (where x = Number of success out of a total of n) will follow Normal Distribution with mean µp = P and standard error σp = √(PQ/n), (where Q = 1-P). 17.1. The problem statement refer to the concise description of the issues that needs to be addressed. Suppose, α has been decided as 5%, so the critical value of test statistic (Z) will be +1.645 (for right tail test), -1.645 (for left tail test). So, the corresponding statistic is = (x̄1 – x̄2). Accordingly, the p-value (two tailed) = 0.688, so the p-value (one tailed) = 0.688/2 = 0.344 > 0.05. He specializes in games for adults and in 1959 he founded his own business as an independent representative of manufacturing in the same astronautically, specializing in games for adults. Weekend challenge #13. As Franklin said both Harsha and Franklin are passed out from the same college in the same year. Descriptive table showing the sample sizes n1=37 and n2=23, sample means x̄1=67.86 and x̄2=78.70, sample standard deviations s1=8.570 and s2= 7.600. Analyze the data and determine whether there is a difference in the mean delivery times in the two wings of the hotel. You have entered an incorrect email address! Data may be collected from each and every unit/person, connected with the problem-situation (totality related to the situation). He has co-authored the famous book "Statistics for Management" (ISBN: 978-93-325-8118-0; Person Publications). The probability distribution of the sample statistic is known as sampling distribution of sample statistic. Statistics are the values characterising the sample i.e. having heavier tails. Here, we take an example of Testing of Mean: This step is used to define the problem after considering the business situation and deciding the relevant hypotheses H0 and H1, after mentioning the hypotheses in the business language. Solution contributed by Ananya Nandan and Munmun Mohanty. It is so known because it assumes no relationship or no difference from the hypothesized value of population parameter(s) or to be nullified. This is a case study written by Hugh McElroy, which is being designed for each year's IBM Corporation. As we discussed in the previous case, for testing of population mean, we assume that sample has been drawn from the population following normal distribution mean µ and standard deviation σ. Since the given data are in 000, it will be better to convert them in thousands.Problem 1Describe the five per cent significance test you would apply to these data to determine whether the new scheme has significantly raised outputs? The analogue of this solution in classical Newtonian theory of gravity corresponds on the gravitational discipline about a point particle. (use alpha = 0.05). This Human Resource Management HRM case study on Employee Relations with solution explains the problems faced by employees with high involvement. A complex and very sensitive grievance raised by a director against the chair of the board. R&R case study #1 And for Parker Bros & Milton Bradley ? Experience Marketing Services reported that the typical American spends a mean of 144 minutes (2.4 hours) per day accessing the Internet via a mobile device. Since population standard deviation is unknown. Here, we assume that sales follow normal distribution with mean µ (unknown) and standard deviation σ (known). to the total sum assured of policies sold by them). WEEKEND CHALLENGE #9 and IIFT CASE STUDY CHALLENGE. A sample of size ‘n’ has been drawn for a normal population N (µ, σ), but population standard deviation σ is unknown, so in this case σ will be estimated by sample standard deviation(s). There are two types of situations (H0 is true or false) which are complementary to each other and two types of complementary decisions (Reject H0 or Failing to Reject H0). Indications are that the sales force is selling more policies, but sales always vary in an unpredictable pattern from month to month and it is not clear that the scheme has made a significant difference. Power of the test.Solution:Let  μ2 = Average sums assured by salesperson AFTER changeover. R&R Case Solution, Describe alternative mechanisms to enter the business. So, there must be some dividing value (s) that differentiates between the two decisions: rejection (critical region) and retention (acceptance region), this boundary value is known as the critical value. The below table is the Independent Sample Test Table, proving all the relevant test statistics and p-values. If two samples are drawn independently without any relation (may be from different units/respondents in the two samples), then it is said that samples are drawn independently. It should be noted that p-value (two tailed test) = 2* p-value (one tailed test). This is known as the problem of Estimation. If hypothesis defines the distribution completely, it is known as Simple Hypothesis, otherwise Composite Hypothesis. R&R case study solution, R&R case study analysis, Subjects Covered Capital costs Development stage enterprises Entrepreneurship by Howard H. Stevenson, Jose-Carlos Jarillo Mossi Source: HBS Premier Case … Heineken – The Progressive Company Heineken is a proud independent and responsible global brewer. If sample statistics is used to estimate the population parameter, then in that situation that is known as the Estimator; {like sample mean (x̄) to estimate population mean µ, sample proportion (p) to estimate population proportion (P) etc.}. Home ; About Us; Meet the Team; Services; FAQ; Help; Upload Case Files; Pricing; Select Page. μ2 = Average sums assured by salesperson AFTER changeover.H0: μ1 = μ2  ; μ2 – μ1 = 0HA: μ1 < μ2   ; μ2 – μ1 > 0 ; true difference of means is greater than zero.Since population standard deviation is unknown, paired sample t-test will be used. Second, since H0 is to be tested so it is H0 only that may be rejected or failed to be rejected (retained). This is known as Census or Complete Enumeration and the ‘totality’ is known as Population. His area of expertise is Business Analytics, Multivariate Data Analysis, Decision Modeling, Soft Operations research etc. (The critical region is shown as a shaded portion in the figure). The Power of the test; We look at a sample homework problem and the R commands necessary to explore the problem. Here, Type I Error = An innocent person is sentenced, while Type II Error = A guilty person is set free. Two samples of size n1 and n2 have been taken randomly from the two normal populations respectively and the corresponding sample means are x̄1 and x̄2. For example, suppose salesperson X has, in the month, sold seven policies for which the sums assured are £1000, £2500, £3000, £5000, £10000, £35000. Students are not sure about which method they have to follow. They are actually functions of sample values e. g. sample mean (x̄), sample standard deviation (s), sample proportion (p) etc. So, we require data to make decisions and to answer the business/functional questions. One part, providing the rejection of H0, known as Critical Region. Depending on method of collection data for the two samples, samples may be termed as independent or dependent samples. We are considering the random variable X = Quarterly sales of the sales executive working in a big FMCG company. Hence, H0 will be rejected for test statistics ≥  1.699127. The employee’s performance and attendance had begun to cause concern and the client was worried. The client identified that in taking on the existing staff they would be overstaffed by 19 employees. Since p-value (=0.06529) is higher than 0.05, we accept (fail to reject) NULL hypothesis. 1(a). Answers are rated by visitors and the best rated answer will be displayed as the best answer for a question. This case study on employee relations with solutions can also be used in explaining other HRM concepts like stress management, promotion, succession planning, etc. The employee’s performance and attendance had begun to cause concern and the client was worried. Here, t statistic will follow t distribution with d.f. Know More, © 2020 Great Learning All rights reserved. When x̄ is significantly above the hypothesized population mean µ0 then H0 will be rejected and the test used will be right tailed test (upper tailed test) since the critical region (denoting rejection of H0 will be in the right tail of the normal curve (representing sampling distribution of sample statistic x̄). We have a team of seasoned and professional case study writers who are experienced in providing case solutions. The scheme has now been in operation for four months. These two tests are also known as One-tailed tests as there will be a critical region in only one tail of the sampling distribution. Hence, H0 got rejected and it can be said that urban outlets are giving lower sales in the first quarter. Solution for HRM Case Study 1. It gives the probability of getting a value of statistic this far or farther from the hypothesised value if H0 is true. R R Case Case Solution is simply among the most basic methods to earn money writing. Prof. (Dr.) Masood H. Siddiqui is a Professor in the area of Decision Sciences & Business Analytics and Dean (Research) at Jaipuria Institute of Management, Lucknow. LinkedIn. Hence, the corresponding test statistic: t = (d̅- θ)/sd/√n will follow t distribution with (n-1). If this figure is an alternative hypothesis, what is: (b)  What is the p-value of the hypothesis test if we test for a difference of $5000? © 2020 Solutions for HR. H0 will be rejected if test statistics > t_critical. R & R Case Case Solution Summary of the case The case study analyzes the opportunities and risks in the gaming industry that Reiss faced in order to succeed. When we consider proportions for categorical data. Each sample has “n” paired observations. (c)   Power of the test:Solution:2.a. Topics: Trivia, Trivial Pursuit, Game Pages: 4 (1343 words) Published: August 23, 2013. The client identified staff recruitment issues. In the last decade Heineken have significantly increased The Samples are said to be dependent or paired. Here, both the outputs for Equal Variance (assumed) and Unequal Variance (assumed) are presented. We continue with the example of Ventura Sales, and want to compare the average first quarter sales with respect to Urban Outlets and Rural Outlets (two independent samples/groups). This is better known as Sampling distribution of the sample statistic. As discussed, hypothesis testing means deciding a rule for rejection/retention of H0. The logic is, since we have evidence only from the sample, we use sample data to decide about the rejection/retaining of the hypothesised value. The p-value (Sig) = 0.460 >0.05, so we can’t reject (so retained) H0. It identifies the issues or gap between the current and desired type of the organization, and thus requires to be stated in order for the management to look for change. Free Case Study Solution & Analysis | Caseforest.com. R & R Case Study Solution Rationale and Discussion on R&R Bob Rises is a graduate of Harvard University in 1956, he worked for a company that made stationary products. The Paired t-Test is applied essentially on one sample while the earlier one is applied on two samples. Our writers have vast knowledge in the field of case studies, and with the help of this knowledge they assist you in your case study regardless the topic and tight deadline. It is known as probability value/ prob. Displays the means by which an experienced contractor can take control of the resources needed to re So, H0 got rejected and it can be said that the claim of average first quarterly sales being 75 (thousand) does not hold. The value of α may be chosen as per the criticality of type I and type II. One Sample Test Table shows the result of the t-test. Solution: Probability of Type I error = significant level = 0.05 or 5%. We want to test the Null Hypothesis: (where θ may take any value as per the situation or θ =0). If ‘Two Independent Samples t-Test’ and ‘Paired t-test’ are applied on the same data set then two tests will give much different results because in case of Paired t-Test, standard error will be quite low as compared to Two Independent Samples t-Test. R&R Case Solution Case Solution. Examining the declaration/perception/claim about the population for its correctness on the basis of sample data. The test is the statistical rule/process of deciding to ‘reject’ or ‘fail to reject’ (retain) the H0. This article makes you familiar with some methods to solve a case study in Management. This free case study on human resource management with answers elaborates the statement ‘Proper communication Channel a way to Effective Management’. A large scale restructure within one primary school due to a steadily decreasing intake of pupils. It allows you to explore the key characteristics, meanings, and implications of the case. Statistical Inference encompasses two different but related problems: 1. Then, the sampling distribution of sample statistic x̄ will follow Normal Distribution with mean µx̄ = µ and standard error σx̄ = σ/√n. C.R. R&R Case Solution. μd = μ2 – μ1   H0: μd = 4000. (n1+n2-2). Shape of t distribution changes with degrees of freedom (exact distribution) and becomes approximately close to Normal distribution for large n. In many business decision making situations, decision makers are interested in comparison of two populations i.e. Are Foxgloves Poisonous To Dogs, Bosch 24'' Fridge, Fallout: New Vegas Skills Console Commands, Elements Of Administration, Milk Vermicelli Calories, Broccoli Salad With Ramen Noodles, 1 Egg White Calories, Cambridge Igcse First Language English Coursebook Fifth Edition Pdf, " />

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Obv.iously, this will generally give the most optimum results with maximum correctness but this may not be always possible. In this stage, a proper sample of size n is taken and after collecting the data, the values of sample mean (x̄) and the observed value of test statistic Zobs is being estimated, as per the test statistic formula. R&R Case Study Solution case analysis, R&R Case Study Solution case study solution, R&R Case Study Solution xls file, R&R Case Study Solution excel file, Today, we are announcing the release of R&R Case Study Solution. Here, since population standard deviation (σ) is known, so the test statistics: Z=  (x- µx̄x)/σ x̄ = (x- µ0)/(σ/√n)  follows Standard Normal Distribution N (0, 1). We’ll keep you up to date with all the latest in employment law and HR. So, we have to figure out whether we should go for ‘equal variance’ case or for ‘unequal variances’ case. But in the situations where population s.d. It is a measure of the extent of variation among different values of statistics from different possible samples. So, the claim stands. The case r = 0 differs, however. 82% of marketers use case studies in their marketing, because it’s such an effective tool to help quickly gain customers trust, and to showcase the potential of your product.. By creating a case study you’re telling potential customers that they can trust you, because … Harvard Case Studies. If the hypothesis parameter falls within the confidence interval, we do not reject H. Hogg, R. V.; McKean, J. W. & Craig, A. T. (2013). Accordingly, the sampling distribution of the sample statistic (sample mean of the differentces di’s) will follow Student’s t distribution with mean = θ and standard error = sd/√n, where sd is the sample standard deviation of di’s. t =  {(x̄1 – x̄2) – (µ1– µ2)}/{√ (s21/n1 +s22/n2)}. JensonR+ donated review time for their expert to carry out due diligence and scrutinise the accompanying data. Following an OFSTED Inspection, the client was issued with an improvement recommendation. The Titan Insurance Company has just installed a new incentive payment scheme for its lift policy salesforce. interested in examining the difference between two population parameters. So, “Equal Variances assumed” case is to be taken up. So, we have to figure out whether we should go for ‘equal variance’ case or for ‘unequal variances’ case. Everything else in the testing process remains the same. inferring about the population on the basis of a sample. All Rights Reserved. A hotel manager looks to enhance the initial impressions that hotel guests have when they check-in. Here, the difference is too small to reject the claim under H0 since the chances (probability) of happening of such a random sample is quite large so we will retain H0. Case studies are included in the Syllabus of management degrees in almost all Universities. One degree of freedom has been sacrificed for estimating population s.d. Demonstrates the methods by which an accomplished business person can pick up control over the important assets keeping in mind the end goal to bring down the settled expenses of business section. While performing Hypothesis-Testing, Hypotheses can’t be proved or disproved since we have evidence from sample (s) only. Get Free Case Studies Solutions related to business, management, marketing and more | Best Case Study Examples and Answers | Learn How to Write a Case Study As discussed earlier, in the situation of Before-After Tests, to examine the impact of any intervention like a training program, health program, any campaign to change status, we have two set of observations (xi and yi) on the same test unit (respondent or units) before and after the program. It consists of dividing the sample space (the totality of all the possible outcomes) into two complementary parts. Since p-value (=0.06529) is higher than 0.05, we accept (fail to reject) NULL hypothesis. Case studies are often a good choice in a thesis or dissertation. Diagrams elective instruments for getting into business. They provide sample standard deviations s1 and s2. Here, the claim is that urban outlets are giving lower sales as compared to rural outlets. Tips and advice on how to protect you and your business. A long-running love requires a lot of commitment and a lot of emotional investment from the audience. R R Case Problem Statement. Plastics Case Study Help - Case Solution & Analysis Case Solutions. Two Sample t-testdata:  WingA and WingBt = 5.1615,df = 38,p-value = 4.004e-06alternative hypothesis: true difference in means is greater than 095 percent confidence interval:1.531895   Infsample estimates:mean of x mean of y 10.3975 8.1225> t.test(WingA,WingB)   Welch Two Sample t-test, t = 5.1615, df = 37.957, p-value = 8.031e-06alternative hypothesis: true difference in means is not equal to 095 per cent confidence interval:1.38269 3.16731sample estimates:mean of x mean of y 10.3975 8.1225. Example: comparing sales of rural and urban outlets, comparing sales before the advertisement and after advertisement, comparison of salaries in between male and female employees, comparison of salary before and after joining the data science courses etc. If Type I error is critical, α is fixed at a low value (allowing β to take relatively high value) otherwise at relatively high value (to minimise β to a low value, Type II error being critical). But the pattern for solving these case studies varies from university to university. t-test is not much affected if assumption of normality is violated provided data is slightly asymmetrical (near to symmetry) and data-set does not contain outliers. Keep your potential customers in mind when creating a customer case study for marketing. Our case solution is based on Case Study Method expertise & our global insights.. Indian (Anglo Saxon) Judicial System considers type I error to be critical so it will have low α for this case. For this purpose, F test can be employed as: Two samples of sizes n1 and n2 have been drawn from two populations respectively. R R Case Harvard Case Study Solution & Online Case Analysis. Lamson Corp. (R) Case Solution, Shows a simulation game that participants can make up to 12 scheduling decisions under conditions of demand uncertainty. Shows the means by which an experienced entrepreneur can gain control of the resources necessary. Difference Between Data Warehousing and Data Mining | Data Mining vs. Data Warehousing, Understanding the Exploratory Data Analysis (EDA) in Python, Top 10 Data Science Companies To Work in the US, Blazing the Trail: 8 Innovative Data Science Companies in Singapore, TravoBOT – “Move freely in pandemic” (AWS Serverless Chatbot), Successfully transformed a mechanical engineer to a data scientist – Ankit Arora, PGP DSE, Wonderful experience at Great Learning- Maharshi Rajodiya, PGP DSE, How to Build a Career in Machine Learning in Singapore, PGP – Business Analytics & Business Intelligence, PGP – Data Science and Business Analytics, M.Tech – Data Science and Machine Learning, PGP – Artificial Intelligence & Machine Learning, PGP – Artificial Intelligence for Leaders, Stanford Advanced Computer Security Program, Sale of the outlet in 1st Quarter(Rs.’000), Test variable (variable under consideration) in the, Enter the relevant pair of variables (paired samples) in the. One Tailed and Two Tailed Tests of Hypothesis: Two Independent Samples t-Test (when Population Standard Deviations are Unknown): > Pvalue=2*pt(tstat, df=n-1, lower=FALSE), > if(Pvalue<0.05)NullHypothesis else "Accepted", > t.test(WingA,WingB, var.equal = TRUE, alternative = "greater"), alternative hypothesis: true difference in means is greater than 0, t = 5.1615, df = 37.957, p-value = 8.031e-06, alternative hypothesis: true difference in means is not equal to 0, To test the effectiveness of the scheme, Titan has taken a random sample of 30 salespeople measured their output in the penultimate month before changeover and then measured it in the fourth month after the changeover (they have deliberately chosen months not too close to the changeover). This belongs to the Confirmatory Data Analysis, as to confirm or otherwise the hypothesis developed in the earlier Exploratory Data Analysis stage. Even if the population is not following the Normal Distribution but for a large sample (n = large), the sampling distribution of x̄ will approach to (approximated by) normal distribution with mean µx̄ = µ and standard error σx̄ = σ/√n, as per the Central Limit Theorem. R&R Case Solution. It is a symmetric distribution (bell shaped distribution). With a strong presence across the globe, we have empowered 10,000+ learners from over 50 countries in achieving positive outcomes for their careers. So they are estimated by sample standard deviations (s1 and s2) from the respective two samples. H0 should be retained. Hypothesis Testing in R- Introduction Examples and Case Study. The test statistic will follow Student’s t distribution with degrees of freedom (rounding down to nearest integers): As discussed in the aforementioned two cases, it is important to figure out whether the two population variances are equal or otherwise. Each sample may provide a value of sample statistic, so there will be a distribution of sample statistic value from all the possible samples i.e. Alternatively, the sample statistic is a random variable, being a function of sample values (which are random variables themselves). Here, we consider a random variable: di = xi – yi. Here, test statistic value (from the sample) is t = -2.376 and the corresponding p-value (2 tailed) = 0.021 <0.05. Knowing about the population-values on the basis of data from the sample. (Source: The 2014 Digital Marketer, available at ex.pn/1kXJifX.) It is assumed that you are familiar will all of the commands discussed throughout this tutorial. the output, it is an example of the one-tailed t-test. Click to read. Higher the standard error, higher is the variation among different possible values of statistics. So, it may be mentioned that the level of significance (α) is the maximum threshold for p-value. It may be further explained as the probability of observing the test statistic if H0 is true i.e. 1-Description of Industry Analysis:-The furniture industry was highly competitive. Life Insurance companies typically measure the monthly output of a salesperson as the total sum assured for the policies sold by that person during the month. implying the success of sales interventions). Problem 2Suppose it has been calculated that for Titan to break even, the average output must increase by £5000. This approach (paired samples) enables us to compare two populations after controlling the extraneous effect on them. Alternative Hypothesis (H1): The hypothesis opposite/complementary to the Null Hypothesis. So, the effectiveness (success) of the sales promotion interventions is doubtful i.e. Here are just a few examples of how Solutions for HR has helped. Case Study The HRM case study with a solution which focuses on the importance of communication in the organization. (b). As per the following output table (Paired Samples Test), sample mean of differences d̅ = -0.417 with standard deviation of differences sd = 8.011 and value of t statistic = -0.403. The value of the population parameter (population mean) to be tested be µ0 (Hypothesised Value). R&R Introduction of Case Study Bob Reiss in 1983 observed with interest the success in the Canadian market of new game board called “Trivial Pursuit”, The sale of the game in the US tended to be approximately ten times those of sales in Canada since “Trivial Pursuit” had sold 100,000 copies.Now Reiss thought game make a boom in US market and this make a profitable opportunity for him. Hypothesis Testing using Standardized Scale: Here, instead of measuring sample statistic (variable) in the original unit, standardised value is taken (better known as test statistic). (The critical regions are shown as shaded portions in the figure). Two-tailed test could have been used if it was asked “new scheme has significantly, Mean of amount assured before the introduction of scheme = 68450, Mean of amount assured after the introduction of scheme = 72000, Difference in mean = 72000 – 68450 = 3550, μ1 = Average sums assured by salesperson BEFORE changeover. it didn’t result in significant increase in sales, provided all other extraneous factors remain the same. What is the p-value of the hypothesis test if we test for a difference of $5000?Solution:Let  μ2 = Average sums assured by salesperson AFTER changeover.μ1 = Average sums assured by salesperson BEFORE changeover.μd = μ2 – μ1   H0: μd ≤ 5000 HA: μd > 5000This is a right tail test. prepared by Lily Hung Jimmy Hu Andrea Tsai Vincent Yu Megan Lu Bruce Lin Howard Hsieh Risks & Rewards Conclusion - Low Entry Barrier - Short Life Circle - Replicability Strategy - Seasonal Vision - Warehousing & Storage This is a common problem in business decision-making because of lack of complete information and uncertainty but by using sample information, the estimate will be based on the concept of data based decision making. To test the validity of this statement, you select a sample of 30 friends and family. It has settled down after fluctuations in the first two months due to the changeover. Rent the Runway is a Harvard Business (HBR) Case Study on Innovation & Entrepreneurship , Fern Fort University provides HBR case study assignment help for just $11. Suppose from a sample, we get a value of sample mean x̄=73. With α = 0.05 and df = 29, critical value for t statistic (or t_critical ) will be   1.699127. The client identified that substantial cost savings were necessary in order to reduce financial deficits. Download PDF. Paired t-Test (Testing Difference between Means with Dependent Samples): We continue with the example of Ventura Sales, and want to compare the average first quarter sales with the second quarter sales. Since these two are probabilistic events, so we measure them using probabilities: α = Probability of committing Type I error = P [Reject H0 / H0 is true]. So, the Hypotheses: Descriptive table showing the sample size n = 60, sample mean x̄=72.02, sample sd s=9.724. (σ) by sample s.d. R & R Case Case Solution,R & R Case Case Analysis, R & R Case Case Study Solution, Critical Analytical Task/Results The first step that is necessary to analyze the critical issues required in the evaluation of a business atmosphere of Search Paper on caseforest database. What conclusion does the test lead to? So the issue is not the difference but actually the magnitude of difference. what are the chances in support of occurrence of H0. Ta. The new scheme has NOT significantly raised outputs. Thera bank case study using r solutions. If this figure is an alternative hypothesis, what is:(a)  The probability of a type 1 error? If we minimize one, the other will increase and vice versa. As we have observed, paired t-test is actually one sample test since two samples got converted into one sample of differences. Major HBR cases concerns on a whole industry, a whole organization or some part of organization; profitable or … Normally α is fixed and we try to minimise β. (The critical region is shown as a shaded portion in the figure). (a) Population Standard Deviations are unknown but equal: In this situation (where σ1 and σ2 are unknown but assumed to be equal), sampling distribution of the statistic (x̄1 – x̄2) will follow Student’s t distribution with mean µx̄ = µ1– µ2 and standard error σx̄ = √ Sp2(1/ n1 + 1/ n2). So, the Hypotheses: H0: µ1– µ2= 0 or µ1= µ2  (Where, µ1= Population Mean Sale of Urban Outlets and µ2 = Population Mean Sale of Rural Outlets). characteristics of the sample. The size (probability/area) of a critical region is taken as α. frequency distribution of sample statistic. R&R Case Solution, Outlines alternative mechanisms for getting into business. μ2 = Average sums assured by salesperson. Sampling distribution of sample proportion p =x/n (where x = Number of success out of a total of n) will follow Normal Distribution with mean µp = P and standard error σp = √(PQ/n), (where Q = 1-P). 17.1. The problem statement refer to the concise description of the issues that needs to be addressed. Suppose, α has been decided as 5%, so the critical value of test statistic (Z) will be +1.645 (for right tail test), -1.645 (for left tail test). So, the corresponding statistic is = (x̄1 – x̄2). Accordingly, the p-value (two tailed) = 0.688, so the p-value (one tailed) = 0.688/2 = 0.344 > 0.05. He specializes in games for adults and in 1959 he founded his own business as an independent representative of manufacturing in the same astronautically, specializing in games for adults. Weekend challenge #13. As Franklin said both Harsha and Franklin are passed out from the same college in the same year. Descriptive table showing the sample sizes n1=37 and n2=23, sample means x̄1=67.86 and x̄2=78.70, sample standard deviations s1=8.570 and s2= 7.600. Analyze the data and determine whether there is a difference in the mean delivery times in the two wings of the hotel. You have entered an incorrect email address! Data may be collected from each and every unit/person, connected with the problem-situation (totality related to the situation). He has co-authored the famous book "Statistics for Management" (ISBN: 978-93-325-8118-0; Person Publications). The probability distribution of the sample statistic is known as sampling distribution of sample statistic. Statistics are the values characterising the sample i.e. having heavier tails. Here, we take an example of Testing of Mean: This step is used to define the problem after considering the business situation and deciding the relevant hypotheses H0 and H1, after mentioning the hypotheses in the business language. Solution contributed by Ananya Nandan and Munmun Mohanty. It is so known because it assumes no relationship or no difference from the hypothesized value of population parameter(s) or to be nullified. This is a case study written by Hugh McElroy, which is being designed for each year's IBM Corporation. As we discussed in the previous case, for testing of population mean, we assume that sample has been drawn from the population following normal distribution mean µ and standard deviation σ. Since the given data are in 000, it will be better to convert them in thousands.Problem 1Describe the five per cent significance test you would apply to these data to determine whether the new scheme has significantly raised outputs? The analogue of this solution in classical Newtonian theory of gravity corresponds on the gravitational discipline about a point particle. (use alpha = 0.05). This Human Resource Management HRM case study on Employee Relations with solution explains the problems faced by employees with high involvement. A complex and very sensitive grievance raised by a director against the chair of the board. R&R case study #1 And for Parker Bros & Milton Bradley ? Experience Marketing Services reported that the typical American spends a mean of 144 minutes (2.4 hours) per day accessing the Internet via a mobile device. Since population standard deviation is unknown. Here, we assume that sales follow normal distribution with mean µ (unknown) and standard deviation σ (known). to the total sum assured of policies sold by them). WEEKEND CHALLENGE #9 and IIFT CASE STUDY CHALLENGE. A sample of size ‘n’ has been drawn for a normal population N (µ, σ), but population standard deviation σ is unknown, so in this case σ will be estimated by sample standard deviation(s). There are two types of situations (H0 is true or false) which are complementary to each other and two types of complementary decisions (Reject H0 or Failing to Reject H0). Indications are that the sales force is selling more policies, but sales always vary in an unpredictable pattern from month to month and it is not clear that the scheme has made a significant difference. Power of the test.Solution:Let  μ2 = Average sums assured by salesperson AFTER changeover. R&R Case Solution, Describe alternative mechanisms to enter the business. So, there must be some dividing value (s) that differentiates between the two decisions: rejection (critical region) and retention (acceptance region), this boundary value is known as the critical value. The below table is the Independent Sample Test Table, proving all the relevant test statistics and p-values. If two samples are drawn independently without any relation (may be from different units/respondents in the two samples), then it is said that samples are drawn independently. It should be noted that p-value (two tailed test) = 2* p-value (one tailed test). This is known as the problem of Estimation. If hypothesis defines the distribution completely, it is known as Simple Hypothesis, otherwise Composite Hypothesis. R&R case study solution, R&R case study analysis, Subjects Covered Capital costs Development stage enterprises Entrepreneurship by Howard H. Stevenson, Jose-Carlos Jarillo Mossi Source: HBS Premier Case … Heineken – The Progressive Company Heineken is a proud independent and responsible global brewer. If sample statistics is used to estimate the population parameter, then in that situation that is known as the Estimator; {like sample mean (x̄) to estimate population mean µ, sample proportion (p) to estimate population proportion (P) etc.}. Home ; About Us; Meet the Team; Services; FAQ; Help; Upload Case Files; Pricing; Select Page. μ2 = Average sums assured by salesperson AFTER changeover.H0: μ1 = μ2  ; μ2 – μ1 = 0HA: μ1 < μ2   ; μ2 – μ1 > 0 ; true difference of means is greater than zero.Since population standard deviation is unknown, paired sample t-test will be used. Second, since H0 is to be tested so it is H0 only that may be rejected or failed to be rejected (retained). This is known as Census or Complete Enumeration and the ‘totality’ is known as Population. His area of expertise is Business Analytics, Multivariate Data Analysis, Decision Modeling, Soft Operations research etc. (The critical region is shown as a shaded portion in the figure). The Power of the test; We look at a sample homework problem and the R commands necessary to explore the problem. Here, Type I Error = An innocent person is sentenced, while Type II Error = A guilty person is set free. Two samples of size n1 and n2 have been taken randomly from the two normal populations respectively and the corresponding sample means are x̄1 and x̄2. For example, suppose salesperson X has, in the month, sold seven policies for which the sums assured are £1000, £2500, £3000, £5000, £10000, £35000. Students are not sure about which method they have to follow. They are actually functions of sample values e. g. sample mean (x̄), sample standard deviation (s), sample proportion (p) etc. So, we require data to make decisions and to answer the business/functional questions. One part, providing the rejection of H0, known as Critical Region. Depending on method of collection data for the two samples, samples may be termed as independent or dependent samples. We are considering the random variable X = Quarterly sales of the sales executive working in a big FMCG company. Hence, H0 will be rejected for test statistics ≥  1.699127. The employee’s performance and attendance had begun to cause concern and the client was worried. The client identified that in taking on the existing staff they would be overstaffed by 19 employees. Since p-value (=0.06529) is higher than 0.05, we accept (fail to reject) NULL hypothesis. 1(a). Answers are rated by visitors and the best rated answer will be displayed as the best answer for a question. This case study on employee relations with solutions can also be used in explaining other HRM concepts like stress management, promotion, succession planning, etc. The employee’s performance and attendance had begun to cause concern and the client was worried. Here, t statistic will follow t distribution with d.f. Know More, © 2020 Great Learning All rights reserved. When x̄ is significantly above the hypothesized population mean µ0 then H0 will be rejected and the test used will be right tailed test (upper tailed test) since the critical region (denoting rejection of H0 will be in the right tail of the normal curve (representing sampling distribution of sample statistic x̄). We have a team of seasoned and professional case study writers who are experienced in providing case solutions. The scheme has now been in operation for four months. These two tests are also known as One-tailed tests as there will be a critical region in only one tail of the sampling distribution. Hence, H0 got rejected and it can be said that urban outlets are giving lower sales in the first quarter. Solution for HRM Case Study 1. It gives the probability of getting a value of statistic this far or farther from the hypothesised value if H0 is true. R R Case Case Solution is simply among the most basic methods to earn money writing. Prof. (Dr.) Masood H. Siddiqui is a Professor in the area of Decision Sciences & Business Analytics and Dean (Research) at Jaipuria Institute of Management, Lucknow. LinkedIn. Hence, the corresponding test statistic: t = (d̅- θ)/sd/√n will follow t distribution with (n-1). If this figure is an alternative hypothesis, what is: (b)  What is the p-value of the hypothesis test if we test for a difference of $5000? © 2020 Solutions for HR. H0 will be rejected if test statistics > t_critical. R & R Case Case Solution Summary of the case The case study analyzes the opportunities and risks in the gaming industry that Reiss faced in order to succeed. When we consider proportions for categorical data. Each sample has “n” paired observations. (c)   Power of the test:Solution:2.a. Topics: Trivia, Trivial Pursuit, Game Pages: 4 (1343 words) Published: August 23, 2013. The client identified staff recruitment issues. In the last decade Heineken have significantly increased The Samples are said to be dependent or paired. Here, both the outputs for Equal Variance (assumed) and Unequal Variance (assumed) are presented. We continue with the example of Ventura Sales, and want to compare the average first quarter sales with respect to Urban Outlets and Rural Outlets (two independent samples/groups). This is better known as Sampling distribution of the sample statistic. As discussed, hypothesis testing means deciding a rule for rejection/retention of H0. The logic is, since we have evidence only from the sample, we use sample data to decide about the rejection/retaining of the hypothesised value. The p-value (Sig) = 0.460 >0.05, so we can’t reject (so retained) H0. It identifies the issues or gap between the current and desired type of the organization, and thus requires to be stated in order for the management to look for change. Free Case Study Solution & Analysis | Caseforest.com. R & R Case Study Solution Rationale and Discussion on R&R Bob Rises is a graduate of Harvard University in 1956, he worked for a company that made stationary products. The Paired t-Test is applied essentially on one sample while the earlier one is applied on two samples. Our writers have vast knowledge in the field of case studies, and with the help of this knowledge they assist you in your case study regardless the topic and tight deadline. It is known as probability value/ prob. Displays the means by which an experienced contractor can take control of the resources needed to re So, H0 got rejected and it can be said that the claim of average first quarterly sales being 75 (thousand) does not hold. The value of α may be chosen as per the criticality of type I and type II. One Sample Test Table shows the result of the t-test. Solution: Probability of Type I error = significant level = 0.05 or 5%. We want to test the Null Hypothesis: (where θ may take any value as per the situation or θ =0). If ‘Two Independent Samples t-Test’ and ‘Paired t-test’ are applied on the same data set then two tests will give much different results because in case of Paired t-Test, standard error will be quite low as compared to Two Independent Samples t-Test. R&R Case Solution Case Solution. Examining the declaration/perception/claim about the population for its correctness on the basis of sample data. The test is the statistical rule/process of deciding to ‘reject’ or ‘fail to reject’ (retain) the H0. This article makes you familiar with some methods to solve a case study in Management. This free case study on human resource management with answers elaborates the statement ‘Proper communication Channel a way to Effective Management’. A large scale restructure within one primary school due to a steadily decreasing intake of pupils. It allows you to explore the key characteristics, meanings, and implications of the case. Statistical Inference encompasses two different but related problems: 1. Then, the sampling distribution of sample statistic x̄ will follow Normal Distribution with mean µx̄ = µ and standard error σx̄ = σ/√n. C.R. R&R Case Solution. μd = μ2 – μ1   H0: μd = 4000. (n1+n2-2). Shape of t distribution changes with degrees of freedom (exact distribution) and becomes approximately close to Normal distribution for large n. In many business decision making situations, decision makers are interested in comparison of two populations i.e.

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