A forestry official is comparing the causes of forest fires in three regions. The following table shows the causes of fire for 100 randomly selected recent fires in these three regions. (in photo)   Test at a 5% significance level whether causes of fire and regions of fires are related.

A researcher gathered a sample of participants who volunteered for a studying of phobias. She measured anxiety level of participants as they viewed photos of spiders and again when they viewed puppies. Which statistical test is appropriate for this study and why?

We are interested in analysing the effect of the lockout laws introduced in some areas of the Sydney CBD and nearby surrounds on the number of alcohol-related violent incidents.  Suppose we have two samples of data on the number of violent incidents in a number of local areas of the Sydney CBD and nearby surrounds. Pubs, hotels and clubs located in a subset of these areas became subject to the lockout laws when they were introduced in 2014. The first sample is from 2010 before the introduction of the lockout laws, and the second is from 2015 after the introduction of the law. The hypothesis we wish to test is that the introduction of the lockout laws reduces violent incidents in the areas in which the lockout laws were put in place.  We use a difference-in-difference model on the pooled data from 2010 and 2015. We find the following results: viol_inc hat = 33.21 (5.29) + 12.43lockout (7.01) – 4.19Yr2015 (2.98) – 3.32 (lockout x Yr2015) (1.85) N = 181, R^2 = 0.128 Where: viol_incis the…

Empathy: The Interpersonal Reactivity Index is a survey designed to assess four different types of empathy. One type of empathy, called Empathetic Concern measures the tendency to feel sympathy and compassion for people who are less fortunate. The index ranges from 0 (less empathetic) to 28 (more empathet The following data, representing random samples of 11 males and 11 females, are consistent with results reported in psychological studies. Boxplots show tha it is reasonable to assume that the populations are approximately normal. Can you conclude that the mean empathy score for men is less than the mean empathy score for women? Let μ₁ denote the mean empathy score for males and μ₂ denote the mean empathy score for females. Use the a=0.01 level and the critical value method with the table. 12 16 13 26 21 23 8 15 18 25 15 Males 21 23 15 26 25 28 24 16 19 20 23 Females Part 1 of 6 Send data to Excel State the appropriate null and alternate hypotheses. H₁ | M₁ = μ₂ H₁ :|µ₁ <µ₂ This is a…

Electric Engineer Co Ltd buys electrical components in batches of 2000. From time to time a batch is randomly selected and, for quality control purposes, all the components are inspected. The data gives the number of defective components found in 90 batches recently bought. 30, 17, 18, 20, 21, 25, 26, 27, 27, 28, 30, 30, 32, 32, 33, 34, 35, 37, 39, 40, 40, 41, 43, 43, 49, 44, 44, 48, 45, 43, 47, 48, 42, 47, 49, 45, 49, 50, 51, 52, 52, 57, 58, 50, 59, 56, 57, 52, 54, 58, 58, 59, 52, 67, 61, 68, 62, 69, 67, 68, 64, 65, 68, 77, 79, 79, 77, 73, 75, 77, 76, 71, 72, 79, 80, 81, 83, 82, 84, 88, 86, 89, 98, 92, 95, 99, 80, 25, 78, 45. (a) Construct a stem and leaf display for the number of defective components. (b) Using the stem and leaf, evaluate the median, lower quartile, upper quartile and the interquartile range of the given distribution. (c) Using graph paper, draw a box and whisker diagram to represent these data and comment on the shape of the distribution. (d) Form a grouped…

Department of Education was analysing the average mathematics test score in the schools in Victoria. It noticed that there were dramatic differences in scores among the schools. In the attempt to improve the scores of all the schools, department attempted to determine the factors that account for the differences. Accordingly, they took a random sample of 40 schools across the state and for each determined the mean test score last year, the percentage of teachers in the schools who have at least one university degree in mathematics, the mean age and the mean annual income of the mathematics teachers. The following is regression output from Excel.               SUMMARY OUTPUT                     Regression Statistics         Multiple R 0.597512         R Square 0.357021         Adjusted R Square 0.303439         Standard Error 7.724526         Observations 40                     ANOVA             df SS MS F Significance F…

A source table has the following information: Three treatment conditions with a sample of n =7 participants in each treatment. You know SS(BW) = 20 and MS(WI) = 2. What is the missing value for MS(BW)? Answer choices: 40, 10, 2, 5 You have an ANOVA source table with the following information: Three treatment groups with a sample of n = 10 participants in each treatment. You also know the SS(BW) =20 and F = 5.00. What is the missing value for SS(Total)? Answer choices: 74, 54, 30, 22 For an experiment involving 2 levels of factor A and 3 levels of factor B with a sample of n = 5 in each treatment condition, what is the value for df(WI)? Answer choices: 30, 29, 24, 20

Restaurant Bill by GenderA study compared the cost of restaurant meals when people pay individually versus splitting the bill as a group. In the experiment half of the people were told they would each be responsible for individual meals costs and the other half were told the cost would be split equally among the six people at the table. In the study, the diners were also chosen so that half the people at each table were female and half were male. We can test for a difference in mean meal cost between females (n1=24, x¯1=44.46, s¯1=15.48) and males (n2=24, x¯2=43.75, s2=14.81).Let group 1 and group 2 be the meal costs for females and males, respectively.   state the null and alternative hypotheses calculate the relevant test statistic find the p-value

GMU uses a robot food delivery service which now has been utilized in the City of Fairfax. One of the potential benefits of this service is to help the busiest students eat breakfast. Research has shown that about 80% of college students skip breakfast due to busy schedules and other reasons. Initial data were collected from a random sample of 595 Mason students who utilize the robot food delivery service and are presented in StatCrunch.    Show the full calculation of the sample proportion by including the number of students who skipped breakfast, the total number of students sampled, and the value of the sample proportion. Present this sample proportion as a decimal rounded to four decimal places. Frequency table results for Breakfast?Count = 595 Breakfast? Frequency Relative Frequency 0 142 0.23865546 1 453 0.76134454

A biologist wants to determine if different temperatures (15oC, 25oC, or 35oC) and amounts of sunlight (partial or full) will affect the growth of plants. He will test each combination of temperature and sunlight by randomly assigning 15 plants to each of the combinations. What type of sampling is described in this study? one sample paired data two samples more than two samples