Name that test! You are the manager of a factory that produces widgets. You believe that widget production will increase based on the number of people working on the assembly line. You test your theory by having three people work together for a random sample of shifts and four people work together for another selection of shifts. What kind of test will you run on your data? a. Chi-square b. None of these c. ANOVA d. Indepenent samples t-test e. Matched pairs t-test f. Regression g. Correlation

Suppose a political science student wants to know whether gender is related in some way to Americans' views on environmental-protection standards. Since this student has an internship at the Environmental Protection Agency (EPA), he asks a simple random sample of 72 EPA employees whether they feel that current environmental regulations are adequate or inadequate. The student summarizes his data in a contingency table so that he can analyze it with a chi-square test for independence. Men Women Adequate 10 16 Inadequate 13 33 The requirements for a chi-square test for independence are not met because the sample is biased. at least one expected cell count is less than 1. either the row or column totals are not random. the categories overlap or do not contain all sample members. the observations are not independent.

2. When you performed null hypothesis tests using a z-test for one sample proportion, what kinds of inferences can you draw about a past population's growth rate if you rejected the null hypothesis that the population proportion was 0.16?

Anyone who has been outdoors on a summer evening has probably heard crickets. Did you know that it is possible to use the cricket as a thermometer? Crickets tend to chirp more frequently as temperatures increase. This phenomenon was studied in detail by George W. Pierce, a physics professor at Harvard. In the following data, x is a random variable representing chirps per second and y is a random variable representing temperature (°F). 21.0 15.1 19.0 17.6 17.5 15.5 14.7 17.1 y 87.8 71.4 94.1 84.7 81.4 75.2 69.7 82.0 15.4 16.2 15.0 17.2 16.0 17.0 14.4 69.4 83.3 79.6 82.6 80.6 83.5 76.3 Find x, and y. Then find the equation of the least-squares line ŷ = a + bx. (Round your answer to four decimal places.) %3D X = y = + %3D Find the value of the coefficient of determination r. What percentage of the variation in y can be explained by the corresponding variation in x and the least-squares line? What percentage is unexplained? (Round your answer for r² to four decimal places. Round your…

C. Test statistics D. Make a decision

Need help in part a and b

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

Just need B. These are old practice problems

A sociologist is interested in the opinion of Minnesota teachers on the recent labor union law passed by Wisconsin lawmakers.   a. What is the experimental unit?   b.What is the population?       c.What are the variables relevant to this study? Classify them as continuous, discrete, nominal, or ordinal.       d. Explain how you would select a sample for this study. Explain pros and cons of your method.

7. Effect size - Cohen's d and r squared An industrial/organizational psychologist has been consulting with a company that runs weekend job-seeking workshops for the unemployed. She collected data on several issues related to these workshops and, after conducting statistical tests, obtained statistically significant findings. She needs to find a way to evaluate effect size so that she can make recommendations to the company. One of the psychologist’s findings is that 18 months after the workshop, a sample of 36 job seekers who received training on resume writing scored an average of 7.3 as measured on a 9-point job-search motivation scale, with a standard deviation of 1.5. The typical job seeker scores 6.1 points. The psychologist finds that the estimated Cohen’s d is    , the t statistic is 4.80, and r² is    .   Using Cohen’s d and Cohen’s guidelines for interpreting the effect size with the estimated Cohen’s d, there is a    treatment effect. Using r² and the extension…