Graphs, variables and methods of data collection - Essay Example

Introduction For data to be presented in a clear way, it can be summarized visually using graphs and charts. Graphs include bar graphs, pie charts, histograms and line graphs. Bar chart and histograms are mostly used for group comparison; pie charts are used for percentage, while line graphs are mainly used to represent numerical data (Aitken 125). Pie chart categorizes data as percentages and each is placed in its own category (Benninga 01). The total of all slices should sum to 100 percent. They are circular in appearance, which allows easy comparison.

On the other hand, bar graphs are mostly used to categorize data into groups. They are divided into numerous pieces, which give clear comparison side by side (Freud 05). For clearer comparison, various graphs should be evenly spaced using the right scale and by observing accuracy when plotting the various points. This paper will examine four types of graphs including Line graphs, Bar Graphs, Pie Charts and Histograms, as presented in different news mediums. In the line graph that is examined, the variable used on the X-axis includes months and that on the Y-axis is revenue in million dollars.

The data collection methods include questionnaires and sampling. This line graph shows that, despite the increase in market share, the income has not increased significantly. The other type of graph that is examined is Pie chart. The variables used here include occupancy in terms of revenue earned, which is shaded in green and un-occupied rooms represented by the un-shaded region. The data collection methods used includes sampling, questionnaires and surveys. The pie charts compare the occupancy rates between years 2007 to 2009 for Ritz-Carlton and All Marriott hotels.

Further, the pie chart shows that Ritz-Carlton has more clients as shown by high occupancy rates compared as with All Marriott brands (Freud 25). Histogram is the third type of graph that is reviewed. The methods of data collection used include questionnaires, surveys, and sampling. The general conclusion is that the histogram compares the sale of light vehicles amongst General motor (GM), Ford, Chrysler, Toyota, Honda and other small manufactures of light vehicles. In addition, the graph shows that many light vehicles were sold by all the companies between 2006 and 2008 as compared to 2009 to 2010 (Jelen 25).

The last graph that is examined is a bar graph. The variables used are fuel consumption in terms of liters, on the X-axis and percentage of sales made, on the Y-axis. Data collection methods include questionnaires and survey methods. This bar chart shows that buyers place more preference on fuel efficient motor vehicles than the fuel guzzlers. A bar graph represents rectangular bars whose lengths are of the same size as values they represent. Further, bars can either be presented vertically or horizontally.

Vertical bar chart is at times referred to as column bar chart (Benninga 01). Bar charts are common with complex comparisons and in presentation of categorical data. The height of the bar tends to correspond with the value it represents in each category. In conclusion, examination of different news mediums has shown that graphs are commonly used to help improve communication. Each of the different types of graphs discussed in this paper presents some ideas in a unique way (Schriver 2). A variety of variables are presented in the graphs, which helps reveal their relationship in a very clear manner.

Essentially, communication of ideas has been made very effective by use of these graphs. Works CitedAitken, Peter. “Excel PivotTables and Charts.” Business Daily. Mar. 2011:122-30. Print.Benninga, Simon. “ Principles of Finance with Excel.” Washington Post. 30 December 2011: LZ01. Print.Freud, Stephen. “Show Me the Numbers: Designing Tables and Graphs to Enlighten.” Washington Post. 24 Feb. 2012:LZ05. Print.Jelen, Bill. “Charts and Graphical representations.” Financial Review. Nov. 2011:56-69. Print. Schriver, Karen.

“Dynamics in Data Representation.” Financial Times. Sept. 1997:24-36. Print. AppendicesLine graphPie chart Bar graphHistogram