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    Descriptive Statistics

    Descriptive Statistics, Reliability and Validity

    1. Reliability vs. Validity. Considering your area of research interest, discuss the importance of reliability and validity. Can you have one without the other? Why or why not? 2. Sample vs. Population. Considering your area of research interest, describe the difference between a sample and population. Why is it important to un


    1. The frequency distribution below was constructed from data collected on the quarts of soft drinks consumed per week by 20 students. Quarts of Soft Drink Frequency 0 - 3 4 4 - 7 5 8 - 11 6 12 - 15 3 16 - 19 2 a. Construct a relative frequency distribution. b. Construct a cumulative frequ

    T-Statistics: Standard Errors

    W. Bowen and T. Finegan (1965) published a paper titled "Labor Force Participation and Unemployment." In that paper they estimated the following regression using a data set of 78 cities: i = 94.2 - .24Ui + .2Ei -.69Ii - .06Si + .002Ci - .8Di (.08) (.06) (.16) (.18) (.03) (.43) The standard errors for the OLS coefficient

    Regression Analysis - Statistics and Minitab

    Management of a soft-drink bottling company wishes to develop a method for allocating delivery costs to customers. Although part of total cost clearly relates to travel time within a particular outlet, another variable reflects the time required to unload the cases of soft drink at the delivery point. A sample of 20 customers wa

    Finding 98% and 99% Confidence Intervals

    1. What is the 99% confidence interval for the variance of exam scores for 25 algebra students, if the standard deviation of their last exam was 10.7? 2. In a sample of 60 mice, a biologist found that 42% were able to run a maze in 30 seconds or less. find the 98% limit for the population proportion of mice who can run that m

    Probability, confidence interval, analysis sample questions

    The area under the normal curve between z=1 and z=2 is ________________ the area under the normal curve between z=2 and z=3. A. Greater than B. Less than C. Equal to D. A, B or C above dependent on the value of the mean E. A, B or C above dependent on the value of the standard deviation Essay Type Questions Please s

    Solving 30 Questions on Descriptive Statistics

    Answer all 30 questions. Make sure your answers are as complete as possible. Show all of your work and reasoning. In particular, when there are calculations involved, you must show how you come up with your answers with critical work and/or necessary tables. Answers that come straight from programs or software packages will not

    Computing Probability Using Poisson Model and Classical Model

    7. A call center receives about 4 calls every minute during peak time. (a) What is the probability that the call center will receive 3 or more calls during a peak minute? (b) If peak time spans 15 minutes, what is the probability that 50 calls will be received during this time period? 8. Six cards are chosen without replac

    Stets on solving some questions on descriptive statistics

    1) Calculate arithmetic mean of:  a. Wages: 75, 100, 120, 150, 200 Total b. Workers: 5, 12, 20, 14, 9 60 2) Calculate the median age:  a. Age Years (Less than): 10, 20, 30, 40, 50, 60, 70, 80 b. No. of persons: 4, 16, 40, 76, 96, 112, 120, 125 3) Calculate Spearman's Rank Correlation:  a. Trainees: A, B, C, D, E, F

    SPSS Analysis of Data

    The Stat_Grades.sav dataset contains data collected about statistics students in three sections of a statistics class taught by an instructor. I attached specific research questions for the analysis along with the dataset. A solution would assist me in understanding descriptive statistics better.

    Independent T-test and SPSS Data Interpretation

    Please review and answer the following questions with short explanations for answers. Review the SPSS output file which reports the results of the independent t-test to compare the mean price per 6-pack for regular vs. reduced calorie brands of wheat beer. Answer the following questions based on your observations of the SPSS

    stats help

    28) police response time to an emergency call is the difference between the time the call is first received by the dispatcher and the time a patrol car radios that it has arrived at the scene. Over a long period of time, it has been determined that the response time has a normal distribution with a mean of 8.4 minutes and a stan

    Statistics: Testing Hypotheses

    The attached file contains the yield for a money market account, a one-year certificate of deposit (CD), and a five-year CD for 23 banks. a) At the 0.05 level of significance, is there evidence of a difference in the mean yield of the different accounts? b) If appropriate, determine which accounts differ in mean yields. c)


    A) SPSS and Data Summary: From the dataset attach, select any two quantitative variables. What is the name of your two quantitative variables you will be analyzing? Use SPSS to compute summary (descriptive) statistics, including measures of central tendency mean, median, mode and numerical measures variance and standard devia

    When the Mode is Better Than the Mean

    1) When is "mode" the better measure? Think about what you have learned and how you can relate it to your profession, your daily life, or a realistic hypothetical situation. 2) Then, create (invent) a realistic small dataset that can be best described by mode and poorly described by mean. 3) List the dataset. 4)

    Descriptive Statistics - Financial

    • Warren Buffett is the Chairman and CEO of Berkshire Hathaway. Even though the firm has approximately 200,000 employees, Mr. Buffett has a staff of under twenty at the Omaha corporate headquarters. Do you believe that more companies should be run in this matter? Why or why not? • Additionally, Warren Buffett typically do

    Finding Critical Value for Z Using Excel Function

    For each of the following situations, find the critical value for Z. a)    H0: P = 0.05 vs. HA: P > 0.05 at α = 0.05. b)   H0: P = 0.6 vs. HA: P ≠ 0.6 at α = 0.01. c)    H0: P = 0.5 vs. HA: P < 0.5 at α = 0.01; n = 500. d)   H0: P = 0.2 vs. HA: P < 0.2 at α = 0.01.


    Time Period Actual Number of Units Sold 1 33 2 36 3 32 4 35 5 33 6 36 7 34 8 38 9 37 10 36 11 38 12 38 13 37 14 39 15 35 16 38 17 37 18 39 19 37 20 35 21 37 22 34 23 35 24 36 1. Based upon using mean absolute deviation (MAD) as a measure of forecast accuracy, which of the forecast models would be the p

    Conducting simple regression and interpretating the results

    //See attached for formatted version// 1.The marketing manager of a large supermarket chain would like to use shelf space to predict the sales of pet food. A random sample of 12 equalized stores is selected, with the following results. Store Shelf Space(X) Weekly sales(Y) 1 5 160 2 5 220 3 5 140 4 10 190 5 10 240 6 1

    Height of Students - Distributions & Deviations Report

    20 students' heights were measured for statistic analysis, with the following results: female 5'6, female 5'8, male 5'9, male 5'6, female 5'7, female 5'5, female 5'6, male 5'10, male 5'8, female 5'4, female 5'4, male 5'9, female 5'1, female 5'5, male 5'11, male 5'7, female 5'6, female 5'8, male 6'1. male 5'9 Please return

    Confidence Interval & Sample Size Calculated Step by Step

    1. If X bar = 85, σ = 8, and n = 64, construct a 95% confidence interval estimate for the population mean, µ. Show work! That is draw the a) normal curve, b) put in the given information(mean and standard deviation), c) identify the area to be solved, d) show the Z conversion of the X values, e) use the Standardized normal T

    Discuss Validity of Central Limit Theorem

    What is the Central Limit Theorem? How large should the sample size be if the underlying distribution of the population values are: a. Normally distributed (discuss). b. Non-normally distributed. (discuss) 2. What is the difference, if any, between the standard deviation of the sample and the standard error of the mean

    Statistics: measures of central tendency

    Table 1 An insurance company evaluates many numerical variables about a person before deciding on an appropriate rate for automobile insurance. A representative from a local insurance agency selected a random sample of insured drivers and recorded, X, the number of claims each made in the last 3 years with the following results

    statistical observation

    A. Select a topic of interest - preferably College related such the height of students or the number of hours they take to prepare for classes. B. Choose 2 variables to observe: 1) Female and 2) Male C. Collect 20 data points on each variable 1. Perhaps, you may design a questionnaire to collect you data 2. The design of you

    MANOVA in Drug Selection

    In this exercise, you are playing the role of a researcher that is testing new medication designed to improve cholesterol levels. When examining cholesterol in clinical settings, we look at two numbers: low-density lipoprotein (LDL) and high-density lipoprotein (HDL). You may have heard these called "good" (HDL) and "bad" (LDL)

    Dependent Sample T-test

    In this activity, we are interested in finding out whether participation in a creative writing course results in increased scores of a creativity assessment. For this part of the activity, you will be using the data file "Activity 4a.sav". In this file, "Participant" is the numeric student identifier, "CreativityPre" contains cr