5 Observations over a long period of time have shown that the mid-day temperature at a particular place during the month of June is normally distributed with a mean value of 23.9 °C with standard deviation 2.3 °C. An ecologist sets up an experiment to collect data for a hypothesis test of whether the climate is getting hotter. She selects at random 20 June days over a five-year period and records the mid-day temperature. Her results (in °C) are as follows. 20.1 26.2 23.3 28.9 30.4 28.4 17.3 22.7 25.1 24.2 15.4 26.3 19.3 24.0 19.9 30.3 32.1 26.7 27.6 23.1 (i) State the null and alternative hypotheses that the ecologist should use. (ii) Carry out the test at the 10% significance level and state the conclusion. (iii) Calculate an unbiased estimate of the population variance and comment on it.

Glencoe Algebra 1, Student Edition, 9780079039897, 0079039898, 2018
18th Edition
ISBN:9780079039897
Author:Carter
Publisher:Carter
Chapter10: Statistics
Section10.5: Comparing Sets Of Data
Problem 13PPS
icon
Related questions
Topic Video
Question
100%
Question and answer key
5 Observations over a long period of time have shown that the mid-day
temperature at a particular place during the month of June is normally
distributed with a mean value of 23.9 °C with standard deviation 2.3 °C. An
ecologist sets up an experiment to collect data for a hypothesis test of whether
the climate is getting hotter. She selects at random 20 June days over a five-year
period and records the mid-day temperature. Her results (in °C) are as follows.
20.1
26.2
23.3
28.9
30.4
28.4
17.3
22.7
25.1
24.2
15.4
26.3
19.3
24.0
19.9
30.3
32.1
26.7
27.6 23.1
(i) State the null and alternative hypotheses that the ecologist should use.
(ii) Carry out the test at the 10% significance level and state the conclusion.
(iii) Calculate an unbiased estimate of the population variance and comment
on it.
Transcribed Image Text:5 Observations over a long period of time have shown that the mid-day temperature at a particular place during the month of June is normally distributed with a mean value of 23.9 °C with standard deviation 2.3 °C. An ecologist sets up an experiment to collect data for a hypothesis test of whether the climate is getting hotter. She selects at random 20 June days over a five-year period and records the mid-day temperature. Her results (in °C) are as follows. 20.1 26.2 23.3 28.9 30.4 28.4 17.3 22.7 25.1 24.2 15.4 26.3 19.3 24.0 19.9 30.3 32.1 26.7 27.6 23.1 (i) State the null and alternative hypotheses that the ecologist should use. (ii) Carry out the test at the 10% significance level and state the conclusion. (iii) Calculate an unbiased estimate of the population variance and comment on it.
(i) H,:H = 23.9°, H,: µ > 23.9°
5
(ii) z= 1.29, significant
(iii) 20.6; the standard deviation 4.54 is much greater
than 2.3 so the ecologist should be asking
whether the temperature has become more
variable.
Transcribed Image Text:(i) H,:H = 23.9°, H,: µ > 23.9° 5 (ii) z= 1.29, significant (iii) 20.6; the standard deviation 4.54 is much greater than 2.3 so the ecologist should be asking whether the temperature has become more variable.
Expert Solution
steps

Step by step

Solved in 5 steps with 2 images

Blurred answer
Knowledge Booster
Propositional Calculus
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, statistics and related others by exploring similar questions and additional content below.
Recommended textbooks for you
Glencoe Algebra 1, Student Edition, 9780079039897…
Glencoe Algebra 1, Student Edition, 9780079039897…
Algebra
ISBN:
9780079039897
Author:
Carter
Publisher:
McGraw Hill