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The Bureau of Labor Statistics reports that the official unemployment rate for Black people was 10.4% and 4.7% for White people in February 2015. Select all correct answers for this question. O The samples of white and black people are independent. The explanatory variable is the unemployment rate. The response variable is the unemployment rate. The response variable is race.

Explain if there was a statistically significant difference between the group means. did you arrive at your conclusion?

What happens to measures of effect size such as r2 and Cohen's d as sample size increases? a. Doesn't influence the effect size. b. They tend to increase. c. They tend to decrease.

An experiment to determine the most effective way to teach safety principles applied four different teaching methods. Some employees were given programmed instruction booklets and worked through the course at their own pace. Other employees attended lectures. A third group watched a television presentation, and a fourth group was divided into small discussion groups. A high of 10 was possible. A sample of five tests was selected from each group. The test grade results were:  Sample Number Programmed Instruction Lecture TV Group Discussion 1 6 8 7 8 2 7 5 9 5 3 6 8 6 6 4 5 6 8 6 5 6 8 5 5 At the 0.01 level, what is the critical value?   Multiple Choice   1.00   1.96   3.24   5.29

Sample surveys on sensitive issues can give different results depending on how the question is asked. A University of Wisconsin study randomly divided 2400 respondents into three groups. All participants were asked if they had ever used cocaine. One group of 800 was interviewed by phone; 21% said they had used cocaine. Another 800 people were asked the question in a one-on-one personal interview; 25% said “Yes.” The remaining 800 were allowed to make an anonymous written response; 28% said “Yes.”101. Was this an experiment or an observational study? Justify your answer.2. Make a two-way table of responses about cocaine use by how the survey was administered.3. Are the differences between the three groups statistically significant? Give appropriate evidence to support your answer

1. A scientist is studying the effect of exercise on blood pressure. He studies 50 people who exercise regularly to find out whether their blood pressures are low, average, or high. This is an example of a(n): Answer choices: sample survey. observational study. experiment.

In the twentieth century, it was a common practice in Southern California for houses to be built with pools in the backyard. For new homes, however, that practice may be changing, possibly as a measure to help reduce climate change. A recent study examined a random sample of 140 houses built in Southern California in the twentieth century and an independent, random sample of 81 new houses built in Southern California. The sample of twentieth century houses contained 61 houses with pools, and the sample of new houses contained 24 houses with pools.Based on this survey, can we conclude, at the 0.05 level of significance, that the proportion p1 of all Southern California twentieth century houses that were built with pools is greater than the proportion p2of all new Southern California houses that were built with pools?Perform a one-tailed test. Then complete the parts below. Carry your intermediate computations to three or more decimal places and round your answers as specified in the…

You are told that the proportion p-hat  of those who answered "yes" to a poll about internet use is p-hat = 0.70, and the standard error of the proportion is 0.0458. What was the sample size?

As a Stock Analyst you compare the performance (measured as average increase in price from 20 may 2020 to 27 may 2020) of two sectors in the American stock exchange. You randomly choose 29 stocks from the finance sector and 29 stocks from the infrastructure and utility sector. This is an example of two dependent samples. INSTRUCTIONS TRUE or FALSE ?