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Seagulls by the seashore Do seagulls show a preference for where they land? To answer this question, biologists conducted a study in an enclosed outdoor space with a piece of shore whose area was made up of 56% sand, 29% mud, and 15% rocks. The biologists chose 200seagulls at random. Each seagull was released into the outdoor space on its own and observed until it landed somewhere on the piece of shore. In all, 128seagulls landed on the sand, role="math" localid="1650465230449" 61landed in the mud, and role="math" localid="1650465221489" 11landed on the rocks. Carry out a chi-square goodness-of-铿乼 test. What do you conclude?

Short Answer

Expert verified

Using the chi-square table, the p-value for the second degree of freedom is 0.000719. The p-value is below the level of significance. The null hypothesis is found to be false. There is enough data to conclude that seagulls have a preference for landing locations.

Step by step solution

01

Given Information

Biologists conducted a study in an enclosed outdoor environment with a section of beach made up of 56percent sand, 29percent muck, and 15percent rocks, according to the query. The biologists randomly selected 200seagulls. Each seagull was released into the open air on its own and watched until it landed on a patch of beach. There were 128seagulls on the sand, 61 in the mud, and 11on the rocks in total. Each seagull was released into the free air and observed until it landed on a beach patch. In total, 128seagulls landed on sand, 61on mud, and 11on rocks.

02

Step 2: Explanation

The null and alternative hypotheses are:

H0:p1=0.56,

H0:p2=0.29,

H0:p3=0.15

Hlocalid="1650465424047" : At least one of pi is different

Following is the calculation of test statistics

The test statistics is

localid="1650618645139" 2=(OE)2/E=14.4742

We can compute the degree of freedom as follow:

localid="1650618876773" Degreeoffreedom=Numberofcategories-1=3-1=2

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