Question

Random collections of nine different solutions of a calcium compound were given to two laboratories, A and B. Each laboratory measured the calcium content (in mmol per liter) and reported the results. The data are paired by calcium compound. Compound 1 2 3 4 5 6 7 8 9 Lab A (x) 13.32 15.83 10.80 11.28 9.61 8.64 12.72 14.09 11.58 Lab B (y) 13.19 15.70 10.67 11.48 9.65 8.63 12.79 14.24 11.55 (a) Rank-order the data using 1 for the lowest calcium reading. Make a table of ranks to be used in a Spearman rank correlation test. Compound Lab A (x) Lab B (y) d = x − y d2 1 2 3 4 5 6 7 8 9 Σd2 = (b) Use a 5% level of significance to test for a monotone relation (either way) between ranks. Interpret the results. What is the level of significance? 0.05 Correct: Your answer is correct. State the null and alternate hypotheses. H0: ρs = 0; H1: ρs ≠ 0 H0: ρs ≠ 0; H1: ρs = 0. H0: ρs = 0; H1: ρs > 0 H0: ρs = 0; H1: ρs < 0 Correct: Your answer is correct. Compute the sample test statistic. (Round your answer to three decimal places.)

Answer #1

(A)

Compound | Lab A | Lab B | Rank(x) | Rank(y) | d = x-y | d^{2} |

1 | 13.32 | 13.19 | 7 | 7 | 0 | 0 |

2 | 15.83 | 15.70 | 9 | 9 | 0 | 0 |

3 | 10.80 | 10.67 | 3 | 3 | 0 | 0 |

4 | 11.28 | 11.48 | 4 | 4 | 0 | 0 |

5 | 9.61 | 9.65 | 2 | 2 | 0 | 0 |

6 | 8.64 | 8.63 | 1 | 1 | 0 | 0 |

7 | 12.72 | 12.79 | 6 | 6 | 0 | 0 |

8 | 14.09 | 14.24 | 8 | 8 | 0 | 0 |

9 | 11.58 | 11.55 | 5 | 5 | 0 | 0 |

Total | 0 | 0 |

(b)

The level of significance is 0.05

The null and alternate hypotheses. H0: ρs = 0; H1: ρs ≠ 0

Sample test statistic =

= 1

Is there a relation between murder and arson? A random sample of
15 Midwest cities (over 10,000 population) gave the following
information about annual number of murder and arson cases.
(Reference: Federal Bureau of Investigation, U.S. Department of
Justice.) City 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Murder 23 10 21
17 22 7 6 9 8 20 18 12 19 11 13 Arson 104 37 121 111 174 26 18 6...

Is there a relation between incidents of child abuse and number
of runaway children? A random sample of cities (over 10,000
population) gave the following information about the number of
reported incidents of child abuse and the number of runaway
children. (Reference: Federal Bureau of Investigation, U.S.
Department of Justice.) City 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Abuse cases 31 36 77 78 73 57 35 108 81 11 111 24...

ADVERTISEMENT

Get Answers For Free

Most questions answered within 1 hours.

ADVERTISEMENT

asked 7 minutes ago

asked 30 minutes ago

asked 43 minutes ago

asked 43 minutes ago

asked 45 minutes ago

asked 45 minutes ago

asked 53 minutes ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago

asked 2 hours ago