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In a hypothesis test the researchers were trying to see if t…

In a hypothesis test the researchers were trying to see if there was statistically significant evidence that the population proportion of fish in a lake that were infected by a parasite had decreased since 2 years ago when the proportion was 22%.  They obtained a p-value of 0.067. a) Would this be a left-tail test, a right tail test, or a 2-tail test? b) Would the results be significant at the 10% significance level?  (just answer yes or no) c) Would the results be significant at the 5% significance level?  (just yes or no) d) If the researchers used the 10% significance level, should they reject or fail to reject the null hypothesis (write reject or do not reject) e) If the researchers used the 5% significance level and made the appropriate conclusion, which type of error are they at risk of making – a type I or a type II error?)   (just answer “type 1” or “type 2”

In a study on passengers who used Chicago’s O’Hare Internati…

In a study on passengers who used Chicago’s O’Hare International airport last summer for a flight, a sample of 230 passengers was observed to try to estimate the mean time through security.  The mean time through security for these passengers was 22.8 minutes.  1) Describe the population of interest in 1 sentence. 2) How do you know the 22.8 minute mean is a statistic (be specific)? 3) What would you have to do to find the value of the parameter?

In a study a sample of 110 vehicles was collected and each v…

In a study a sample of 110 vehicles was collected and each vehicle was tested for its city miles per gallon (x) and its highway miles per gallon (y).  This data set is on stat key titled “Cars (Highway MPG vs CityMPG”.  Access the data (you’ll need to know which data types we are working with to select the right descriptive statistics and graphs area) and using the stat key output, give the following.   a) The value of r (correlation coefficient) b) The equation of the linear regression line (no hat is needed, you can just type it in here) c) Write a sentence that interprets the value of the slope of the regression line, in context. d) Looking at the stat key graph, one case appears to have the most negative residual.  If you have your cursor point to this case it will show you the x and y values.  Give the coordinates (either as an ordered pair or list x and y separately).