BAN 280 Exam 1 Questions And Answers Fully Solved.

Population - correct answer a collection of persons, objects, or items of interest Census - correct answer an examination of each and every measurement of the entire population Sample - correct answer a subset of measurements selected from the population Parameter - correct answer A measurement from a population Statistic - correct answer A measurement from a sample continuous data - correct answer Numerical data values that can be MEASURED Ex. The weight, in ounces, of the apple butter poured into jars on an assembly line. discrete data - correct answer Numerical data values that can be COUNTED Ex. The humber of students in class today 4 scales of measurement - correct answer nominal, ordinal, interval, ratio Nominal scale - correct answer The lowest level of data measurement. Not necessarily numerical. Levels or categories or simply assigned values. Ex. male or female Ordinal scale - correct answer the same as nominal but adds extra properties that can be ordered. Ex. 1-very satisfied - 2-satisfied - 3-fair - 4-unsatisfactory This level of measurement is higher than nominal. Interval Scale - correct answer A numerical scale that is higher than nominal and ordinal data. Most of the data we use in statistics should be in at least interval data. Ex. Temeperature scale (F) / Percentage change in employment Ratio scale - correct answer The highest level/scale of data measurement. Has a definite zero point whereas interval scale does not. This is the only difference between these two scales. The zero allows the data to define a ratio. Ex. used in all physical measurements - height, weight, length, time, volume, blood pressure, cholestreol levels. / Kelvin scale for temperatures. Types of Data - correct answer Primary, secondary, time series, cross sectional, census Primary data - correct answer When the investigator collects the data himself. Here the data is collected by the person who is doing the research. Secondary data - correct answer When the data is taken from some published source. AKA when the data is collected by someone other than the principal investigator. time series data - correct answer A sequence of observations that are taken in an orderly fashion with respect to time. Most business data is time series data. frequency distribution - correct answer an arrangement of data that indicates how often a particular score or observation occurs relative frequency distribution - correct answer The fraction of the total number of observations relative to the class OR sample. Pie chart - correct answer The simplest form of graphical representation of a frequency or relative frequency distribution Runs plot - correct answer A graph of a process over time. This type of chart shows time series data. Scatter plot - correct answer a graph that shows all of the sets of X & Y data points with no connecting lines. Best used to observe patterns in data. Histogram - correct answer A graph that looks like a bar graph and shows the frequency distribution or relative frequency distribution of the data. Quartiles - correct answer Dividers to sort data into four different groups. Q1 (First 25%) Q2 (middle 50%) also the median Q3 (First 75% or Upper 25%) How to find quartile locations - correct answer Arrange data from smallest to largest, Q1: # of items(25/100)=Q1 Q2: # of items(50/100) = Q2 Q3: # of items(75/100)=Q3 Always round to nearest whole number. 5 point summary - correct answer Consists of five data values: the lower extreme value the first quartile the median the third quartile upper extreme value. stem and leaf display - correct answer Chart used to observe the shape of the data. grade school shit box-and-whiskers display (box plot) - correct answer a graphical data summarization that allows you to study quartile groupings how to find interquartile range - correct answer Q3-Q1 To find the 36th percentile you would... - correct answer multiply n times 34, then divide by 100 The fence for a box plot: - correct answer assists in identifying outliers equals the IQR times 1.5 central tendency - correct answer Measures are used to quantify the middle or central location of a probability distribution. Most commonly, the word "average" is used to describe central tendency. Mean is most commonly used to calculate this. Dispersion - correct answer a measure of the variability or spread of your data around the central tendency of data. the population mean - correct answer μ = mu Used in census population data The sample mean - correct answer x̅ = xbar Used to estimate the population mean from samples Mode - correct answer the observation that occurs the most within a given data set Skewness - correct answer Judged by looking at the relative position in relation to the mean, median, and mode. Data skewed to the right = positively skewed Data skewed to the left= negatively skewed Direction of the "tail" indicated wether there is a positive or negative skew Range - correct answer The difference between Symbol for sample standard deviation - correct answer S Empirical Rule - correct answer For normal populations states that: 68% of the data will lie within Mu +/- 1 standard deviation 95% of the data will lie within Mu +/- 2 standard deviations