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Descriptive Statistics

Descriptive statistics is the process of summarizing data in both a quantitative and visual manner. In a quantitative sense, typically this involves highlighting the main elements of a collection of data, for example, calculating the mean, median and mode. It is through the construction of figures, such as histograms and pie charts that data can be visually represented. Essentially, the overarching goal with descriptive statistics is to characterize data so that the basic quantitative features can be properly understood.

In descriptive statistics, the method which is utilized to express data depends on the type of data which is being analyzed. Simply put, data can be separated into two general groups: categorical data and numerical data. When dealing with categorical data, the variables which are measured are usually either nominal or ordinal in nature. A nominal variable is one representative of a category, with no associated numerical value. For example, data collected on the different colours of hummingbirds in a sample would represent nominal data. However, ordinal variables do have associated intrinsic values, usually classified as levels or rankings. For example, pretend that in the hummingbird scenario only yellow hummingbirds were measured in terms of the intensity of yellow which they possessed, either being low, medium or high. Therefore, these three levels of intensity would represent ordinal variables.

In comparison to categorical data, numerical data classifies variables as being either continuous or discrete. Discrete variables are whole numbers, whereas, continuous variables can resemble any number within a range.

Descriptive statistics is an integral part to the analysis of data because it allows data to be represented in a visual way, in which patterns and outliers can be identified. The use of descriptive statistics is useful for any study which aims to describe the characteristics of the different measures being collected. Additionally, it is critical to understand that descriptive statistics does not aim to formulate inferences which extend beyond the sample data being studied to the population at large. Rather, it functions to solely evaluate and visualize the immediate data collected.

Categories within Descriptive Statistics

Solve a set of questions on binomial distribution

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Descriptive Statistics and Samples Versus Population

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Emily Smith decides to buy a fuel-efficient used car

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Perform a hypothesis testing for mean using t distribution

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Basic number statistics

Hi, Please I want help to answer these questions. Thanks. 1) The students of Hugh Logan's math class took the Scholastic Aptitude Test. Their math scores are shown below. Find the mean score. 552 593 358 352 537 349 357 596 470 482 2) The salaries of ten randomly selected physicians are shown below. Find the median

Investment Statistics - Value of Information

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Frequency Distribution Scenario for Motivating Buying Habits

Scenario: Your boss has asked you to analyze the ages of your customers to get a better idea of what might motivate their buying habits. Outside research has shown that different age groups buy products for different reasons. And that different age groups buy different kinds of products. Your boss developed a survey that was sen

Excel Grade Book Project

Excel Grade Book Project Understanding how weighted averages work will be a very important topic for you in this course, since your grades are determined in this way. In this project, you will create an Excel spreadsheet that can calculate a math 123 student's final grade for the course. You will then write a reflection pap

Solve 15 questions on decision theory

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Decision Errors: Alpha and Power Relationship

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Research questions using hypotheses testing in real life

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Descriptive Statistics Calculation

Must show all work leading to answers- Can you please show all detailed work leading to the answer? MAT 142 Problem set Unit: Statistics Topic: Organizing and Visualizing Data Directions: Solve the following problems. Please show your work, and explain your reasoning. Consider the set of test scores shown below 88, 8

Project 3 Google Stock Closing Prices

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Forecasts Calculations

Question 4 A rendering plant wishes to use the data (sales records from a few local businesses and the month of the year) to help determine their supply level for the coming months. The records shown in the table provide an excellent opportunity for you to assist them with their forecasting. Which answer below? Month Sales

Coefficients for Both Simple and Multiple Regressions

See the attached file. 1. A professor wants to test if the number of sunny days in the week before an exam has an influence on student grades .A sample of 20 is taken and the following regression equation is obtained. Y = 80 - .5X S b1 = .1 a) Test at a=.05 b) Interpret R2 2. Given the following regression

Graphical & Tabular Descriptive Summaries

Using the attached excel file, identify and discuss what makes a Crusty Pizza Company restaurant successful and conversely unsuccessful. Use the data for the 60 stores in worksheet "Case 1 and 2 data". Use graphical and tabular descriptive statistics. Plan the analysis by using a combination of summaries that best allow you to

Frequency Distribution with Skewed Data

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Assumptions, Calculations, and Confidence Interval for Means

Your manager is asking for the average viscosity of a product that you produce in a batch process. Recorded below are the 12 most recent values, taken from consecutive batches. State any assumptions, and clearly show the calculations that are required to estimate a 95% confidence interval for the mean. Interpret that confidence

Descriptive Statistics, Reliability and Validity

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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