6. Suppose that the researcher from the previous problem repeated the study of married couples' initials using twice as many participants and obtaining observed frequencies that exactly double the original values. The resulting data are as follows: Same Different Initial Initials 38 362 400 a. Use a chi-square test to determine whether the number of couples with the same last initial is significantly different that would be expected if couples were matched randomly. Test with a = .05. b. You should find that the data lead to rejecting the null hypothesis. However, in problem 5 the deci- sion was fail to reject. How do you explain the fact that the two samples have the same proportions but lead to different conclusions?

For the following data 4,4,6, 10 o = 2.4 Then C.V.= Select one: O a. 25% O b. 47% Ос. 22.4% d. 40%

1.18 Cats on YouTube. Suppose you want to estimate the percentage of videos on YouTube that are cat videos. It is impossible for you to watch all videos on YouTube so you use a random video picker to select 1000 videos for you. You find that 2% of these videos are cat videos. Determine which of the following is an observation, a variable, a sample statistic (value calculated based on the observed sample), or a population parameter

.

Consider the following two questions designed to assess quantitative literacy. 1. What is 15% of 1000? 2. A store is offering a 15% off sale on all TVs. The most popular television is normally priced at $1000. How much money would a customer save on the television during this sale? Suppose the first question is asked of 200 randomly selected college students, with 165 answering correctly; the second one is asked of a different random sample of 200 college students, resulting in 143 correct responses. Carry out a test of hypotheses at significance level 0.05 to decide if the true proportion of correct responses to the question without context exceeds that for the one with context. (Use p₁ for the true proportion students who answered the question without context correctly and p₂ for the true proportion of students who answered the question with context correctly.) State the relevant hypotheses. Ho: P₁ P₂ = 0 Ha: P₁ P₂ #0 Ho: P₁ Ha: P₁ Ho: P₁ Ha: P₁ Ho: P₁ Ha: P₁ USE SALT O Ho: P₁ Ha: P₁…

1. A dog groomer is often asked if small dogs bark more than larger dogs. To test this, he logs the number of separate barking episodes per day for three size dogs: small, medium, and large. In a separate file you will find the number of barking episodes for 12 dogs. On average, small dogs barked the most Mean: 7.25 On average, medium sized dogs barked the least Mean: 2.75 A. Do the different size dogs bark a significantly different number of times? Test with an α = 0.05. B. If appropriate, use Tukey’s HSD post hoc test and report where the differences are. If inappropriate, state why. C. Calculate and interpret the effect size.

Use the following scenario for questions 1-4: Dr. Wiese wants to determine whether duration of pregnancy and type of opiate use among pregnant women predict developmental delays in their children. In a sample of 30 new mothers, Dr. Wiese measured the duration of their pregnancies (premature, mature, postmature) and the type of opiate that they used during pregnancy (oxycodone, heroin). All participants' babies were then rated on how closely they have met developmental milestones on a scale ranging from 1-10.  1. Identify one of the independent variables. How many levels does this variable have? 2. Identify the other independent variable. How many levels does this variable have? 3. This study is a .............x ...................factorial design.

12. The following dotplot shows the results from a previous class. The average word 1 is the Average Word length when students selected their own words and Average Word 2 is when the words were randomly selected. Variable 7 Average Word-2800 88..... Average Word-1- The population mean for word length is 4.3 letters. Comment on results from both graphs and the ability to predict the population mean from a sample. Your answer should be a college level paragraph that consists of a topic sentence, supporting sentences and a concluding sentence.