Mrs. Greenback a financial analyst hired an advertising agency
to advertise her mutual funds to the public. Before she hired the
advertising agency, she received on average (mean) 200 calls from
new investors per week (50 weeks), with a standard deviation of 16
calls per week. Mrs. Greenback would like to investigate whether
there has been an overall change in the number of calls received
weekly after she hired the advertising agency. After she hired the
advertising agency, she started to receive 206 calls per week (50
weeks). To put it another way, did the mean number of inquiries per
week differ significantly from 200 calls per week after she hired
the advertising agency?
What is your decision at 0.01 significance level?
Grupo de opciones de respuesta
Reject the null hypothesis (Ho) and conclude that the advertising agency did increase the mean number of calls at 0.01 significance level.
Do not reject the alternative hypothesis (H1) as the advertising agency did not increase the mean number of calls at 0.01 significance level.
Do not reject the null hypothesis (Ho) as the advertising agency did not increase the mean number of calls at 0.01 significance level.
Reject the alternative hypothesis (H1) as the advertising agency did increase the mean number of calls at 0.01 significance level.
Given that
number of weeks =n=50
sample mean =m=206
population SD=SD=16
we have to test that
now test statistics is given by
now P-Value =P(Z>2.652) =0.004
since P-value is less than level of significance hence we reject H0 that is we have enough evidence to support the claim that there is increase in the number of calls from 200.
Hence correct option is
Reject the null hypothesis (Ho) and conclude that the advertising agency did increase the mean number of calls at 0.01 significance level.
Mrs. Greenback a financial analyst hired an advertising agency to advertise her mutual funds to the...
A pediatrician was surprised to find many of her young patients had blood cholesterol levels over 5 mmol/L, indicating an increased risk of coronary artery disease. She took a random sample of 30 such patients to take part in a special nutritional program designed to lower blood cholesterol. Ten weeks after the program started, she measured the cholesterol levels of each of the 30 patients again. a. With the before and after program data for each of 30 patients on...
A random sample of companies in electric utilities (I), financial services (II), and food processing (III) gave the following information regarding annual profits per employee (units in thousands of dollars). I II III 49.9 55.6 39.4 43.8 24.7 37.5 32.3 41.3 10.9 27.3 29.3 32.3 38.5 39.3 15.2 36.2 42.5 20.6 Shall we reject or not reject the claim that there is no difference in population mean annual profits per employee in each of the three types of companies? Use...
Please answer all 3 questions mpus A test of sobriety involves measuring the subject's motor skills. Twenty randomly selected sober subjects take the test and produce a mean score of 41.0 with a standard deviation of 3.7. At the 0.01 level of significance, test the claim that the true mean score for all sober subjects is equal to 40.0. Use the traditional method of testing hypotheses. The results for the test turn out to be: Hopp = 40.0.HAP 40.0. Test...
An employment agency wants to see which of three types of ads in the help-wanted section of local newspapers is the most effective. Three types of ads (big headlines, straightforward, and bold print) were randomly alternated over a period of weeks, and the number of people responding to the ads was noted each week. Type of Advertisement Big Headline Straightforward Bold Print Number of responses (replicates) 26 24 33 30 24 28 45 31 34 35 25 42 40 22...
A police department released the numbers of calls for the different days of the week during the month of October, as shown in the table to the right. Use a 0.01 significance level to test the claim that the different days of the week have the same frequencies of police calls. What is the fundamental error with this analysis? Fri Day Frequency Sun 160 Mon 205 Tues 220 Wed 250 Thurs 170 Sat 240 208 Determine the null and alternative...
A. B. Please follow the steps of hypothesis testing, including identifying the alternative and null hypothesis, calculating the test statistic, finding the p-value, and making a conclusions about the null hypothesis and a final conclusion that addresses the original claim. Use a significance level of 0.10. Is the conclusion affected by whether the significance level is 0.10 or 0.01? Test Statistic=______ (Round to two decimal places) P-Value=______ (Round to three decimal places) Answer choices below: a) Yes, the conclusion is...
We're interested in the amount of time spent at work by college graduates employed full-time. The standard amount of time spent at work by full-time employees is 40 hours per week. We suspect that the mean number μ of hours worked per week by college graduates is more than 40 hours and wish to do a statistical test. We select a random sample of 100 college graduates employed full-time and compute the mean number of hours worked per week by...
An attorney claims that more than 25% of all lawyers advertise. A random sample of 200 lawyers in a certain city showed that 63 had used some form of advertising. At a 0.05, what would be your conclusion regarding the hypothesis test? O Accept the null hypothesis and the test is insignificant. O Reject the null hypothesis and the test is significant O Cannot be determined. A researcher wishes to see if the average weights of newborn male infants are...
Suppose a geologist believes that the average chloride concentration in her local water supply is above the national average of 75 ppm. The geologist defines a null hypothesis, Ho:u = 75 ppm, to reflect the mean chloride concentration in the national water supply. She formulates an alternative hypothesis, H1: u > 75 ppm, to indicate that her locality has a higher concentration of chloride in its water supply, on average. In these hypotheses, y represents the true mean concentration of...
can dba & standard... tics T test With Data Aation and Linear Reg... 184: Linear Regression ad: In Exercise, use Ta... About the correlatio... al Estate Agency Says.. The table below shows the number of hours per day 11 patients suffered from headaches before and after 7 weeks of soft tissue therapy. At 0.01, is there enough evidence to conclude that soft tissue therapy helps to reduce the length of time patients suffer from headaches? Assume the samples are random...