Answered: Define the following terms: a.…

Name: Define the following terms:a. Observational studyb. Designed experimen
Uploaded: 2024-03-20T07:07:37.000Z
Channel: Bartleby
Description: Define the following terms:a. Observational studyb. Designed experiment

Math

Statistics

Define the following terms: a. Observational study b. Designed experiment

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

See similar textbooks

Similar questions

3. Amarket research firm needs to collect data on viewer preferences for local news programming in Rochester. Which method of data collection is most appropriate? a. Survey b. Observational Study C. Census d. Controlled Experiment
A certain company will purchase the house of any employee who is transferred out of state and will handle all details of reselling the house. The purchase price is based on two assessments, one assessor being chosen by the employee and one by the company. Based on the sample of eight assessments shown, do the two assessors agree? Use the .01 level of significance. Assessments of Eight Homes ($ thousands) Assessed by Home 1 Home 2 Home 3 Home 4 Home 5 Home 6 Home 7 Home 8 Company 328 350 455 278 290 285 535 745 Employee 318 345 470 285 310 280 525 765 a) Choose the appropriate hypotheses. Assume d = company assessed value – employee assessed value. H0: μd = 0 versus H1: μd ≠ 0. H0: μd ≠ 0 versus H1: μd = 0. (b) State the decision rule for .01 level of significance. (Round your answers to 2 decimal places. A negative value should be indicated by a minus sign.) Reject the null hypothesis if tcalc < or tcalc > . (c-1) Find the test statistic tcalc.…
In Exercises 29–32, indicate whether the observational study used is cross-sectional, retrospective, or prospective. Framingham Heart Study The Framingham Heart Study was started in 1948 and is ongoing. Its focus is on heart disease.
Determine the treatment group, control group, and treatment for the following study:A researcher may want to study whether taking folic acid before pregnancy will decrease the risk ofbirth defects
Which method II? Which of the following scenariosshould be analyzed as paired data?a) Spouses are asked about the number of hours of sleepthey get each night. We want to see if husbands getmore sleep than wives.b) 50 insomnia patients are given a placebo and 50 aregiven a mild sedative. Which subjects sleep more hours?c) A group of college freshmen and a group of sophomoresare asked about the quality of the university cafeteria. Dostudents’ opinions change during their time at school?
Order the following epidemiologic study designs (from 1 being the best, to 8 being the worst) in terms of their effectiveness in supporting causal inference. a) case report or cass series b) cross sectional study c) ecological study d) case-control study e) prospective cohort study f) retrospective cohort study g) randomized, double-blind experimental study h) community experimental study
Consider a study where the objective is to determine whether the type of frame of a bicycle could affect your travel time to work. On each of 56 days from mid-January to mid-July 2010, Dr Jeremy Groves tossed a coin to decide whether he would ride the 27 miles to work on his carbon frame bicycle or on his steel frame bicycle. He collected the following data: Carbon frame: Sample size: 26 days Mean commute time: 108.34 minutes SD: 6.25 minutes Steel frame: Sample size: 30 days Mean commute time: 107.81 minutes SD: 4.89 minutes Suppose we use as sample statistic the difference in sample means (108.34 - 107.81). Find the lower limit of a theory-based 99% confidence interval. Round your answer to 3 decimal places.
A social worker in South Phoenix delivered an intervention on financial literacy. The program is six weeks long (one hour per week). She collected pre and post- test surveys in order to determine if participants’ knowledge on financial literacy increased due their involvement in the program. Review the table below and answer the following questions. Table 1. Financial literacy intervention change from pre to post test M SD t p Financial Literacy Knowledge 5.04 .001 Pre test 7.25 1.78 Post test 8.42 1.20 1. Was a dependent or independent t-test used to analyze the data? How do you know?
Firefighters use of gas detection devices. Two deadlygases that can be present in fire smoke are hydrogencyanide and carbon monoxide. Fire Engineering (March,2013) reported the results of a survey of 244 firefightersconducted by the Fire Smoke Coalition. The purpose ofthe survey was to assess the base level of knowledge offirefighters regarding the use of gas detection devices atthe scene of a fire. The survey revealed the following:Eighty percent of firefighters had no standard operatingprocedures (SOP) for detecting/monitoring hydrogencyanide in fire smoke; 49% had no SOP fordetecting/monitoring carbon monoxide in fire smoke. Assume that 94% of firefighters had no SOP for detecting either hydrogen cyanide or carbon monoxide in fire smoke What is the probability that a firefighter has no SOP for detecting hydrogen cyanide and no SOP for detecting carbon monoxide in fire smoke?
1. Most supermarkets across the United States have invested heavily in optical scanner systems to expedite customer checkout, increase checkout productivity, and improve product accountability. These systems are not 100% effective, items often have to scan several times. Sometimes items are entered into the manual cash register because the scanner cannot read the item number. The following data are from an experiment in which a supermarket selected 20 of the best checkers and measured their productivity both when using a scanner and when working manually. In general, do optical scanners register significantly more items than manual entry systems do? At significant level=0.05. (1 Checker 1 2 3 18 16 17 19 20 4 5 6 7 11 12 13 14 15 8 9 10 Manual 426 387 410 506 411 398 427 449 407 438 418 482 512 402 435 397 421 426 475 453 Scanner 473 446 421 510 465 409 414 459 502 439 456 499 518 437 435 411 415 421 485 490
Why is a cohort design more efficient than a case-control design to study a rare exposure? (Select one best answer) Group of answer choices a. Subjects are selected based on their exposure status. b. Subjects are selected based on their disease status. c. Subjects are selected based on their exposure and disease status. d. Subjects are selected based on their random allocation to treatment or placebo. e. None of these.
For quality assurance, every fifth package on an assembly line is selected and tested for durability. Part a: Is the survey method likely to result in a representative sample? Part b: If not, suggest a better survey method.