A recruitment consultant is tasked with evaluating 7 potential employees for a software engineering role. The consultant interviews the candidates and ranks them in order of their suitability for the company culture.
The consultant's ranked order, from most suitable to least suitable, is: J,K,G,M,I,H,LJ, K, G, M, I, H, LJ,K,G,M,I,H,L.
Independent of the interview, the candidates each completed a technical coding assessment. Their scores (out of 50) are provided in the table below:
| Candidate | G | H | I | J | K | L | M |
|---|---|---|---|---|---|---|---|
| Score | 35 | 31 | 39 | 49 | 46 | 25 | 42 |
Calculate Spearman's rank correlation coefficient between the consultant's suitability ranking and the ranking based on the technical assessment scores. Use a rank of 1 for the highest score/suitability. Show your working clearly.
Using a 5% level of significance, test whether there is evidence of a positive correlation between the consultant's ranking and the technical assessment ranking. State your hypotheses and the critical value.
Explain why Spearman's rank correlation coefficient is more appropriate than the Product Moment Correlation Coefficient (PMCC) for analyzing the relationship in this specific task.
The recruiter realizes that Candidate K's score was recorded incorrectly. If K's score were corrected to 49, explain what effect this would have on the rankings of the technical scores.
316 exam-style questions on OCR A Level Maths 2.5 Statistical Hypothesis Testing, covering 2.5.1 The language of hypothesis testing, 2.5.2 Hypothesis test for a binomial proportion, 2.5.3 Inference and significance level, 2.5.4 Sample mean as a random variable (A-level only), 2.5.5 Hypothesis test for the mean of a normal distribution (A-level only), 2.5.6 Pearson's product-moment correlation coefficient, and 2.5.7 Hypothesis test using Pearson's coefficient (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.