mabel made a change to the website she runs, and she wonders how it affected the way people navigate to the…

mabel made a change to the website she runs, and she wonders how it affected the way people navigate to the website—from a web search, from social media, or directly by entering the websites address. she took a random sample of 170 visits before she made the change, and then she took a random sample of 170 visits after she made the change. here are the results: mode of navigation before after total search 78 95 173 social media 57 71 128 direct 35 4 39 total 170 170 340 mabel wants to perform a $chi^{2}$ test of homogeneity on these results. what is the expected count for the cell corresponding to navigation from social media before mabel made the change? you may round your answer to the nearest hundredth. expected:

mabel made a change to the website she runs, and she wonders how it affected the way people navigate to the website—from a web search, from social media, or directly by entering the websites address. she took a random sample of 170 visits before she made the change, and then she took a random sample of 170 visits after she made the change. here are the results: mode of navigation before after total search 78 95 173 social media 57 71 128 direct 35 4 39 total 170 170 340 mabel wants to perform a $chi^{2}$ test of homogeneity on these results. what is the expected count for the cell corresponding to navigation from social media before mabel made the change? you may round your answer to the nearest hundredth. expected:

Answer

Answer:

63.94

Explanation:

Step1: Identify row - total, column - total and grand - total

Row total for social media = 128, Column total for before = 170, Grand total = 340.

Step2: Use formula for expected count

The formula for the expected count in a $\chi^{2}$ test of homogeneity is $E=\frac{\text{Row Total}\times\text{Column Total}}{\text{Grand Total}}$. So, $E=\frac{128\times170}{340}$.

Step3: Calculate the value

$E=\frac{21760}{340}=63.941176\approx63.94$.