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2 Introduction This workbook accompanies the computer skills training workshop. The trainer will demonstrate each skill and refer you to the relevant page at the appropriate time. This workbook can also be used independently at home. Work at your own pace during the workshop If you prefer to work through the workbook at your own pace, rather than follow the pace of the workshop, please feel free to do so. However, we would appreciate you refraining from asking questions until after the relevant section has been covered by the trainer. Improve your skills at home If you find it difficult to attend our workshops, or prefer to study independently, you can download our workbooks and exercise files wherever you are assuming you have a working internet connection. Downloading the exercise files for this workbook The exercises referred to within this (and other) workbook(s) can be downloaded from: Downloading other workbooks All our workbooks can be downloaded from: About us Our aim is to support you in your use of IT while studying at the University of Bedfordshire. Our computer skills training workshops are designed to help you to improve your IT skills so you can efficiently complete assignments and dissertations. Our workshops range from Fundamentals workshops which are suitable for complete beginners to workshops that cover more advanced skills. Our regular workshops are scheduled during academic terms, and published on the Learning Resources website: If you have an individual training need, please contact us to discuss your requirements. Contact us Linda Martin / Rosa Ramos cst@beds.ac.uk

3 Contents Introduction...i Status bar statistics... 1 Introducing functions... 2 Copying formulas... 3 The SUM and AVERAGE Function... 4 The MAX and MIN Functions... 5 Calculating Mode, Median and Standard Deviation... 6 Using the CORREL Function... 7 The FREQUENCY function... 8 The IF Function... 9/10 The COUNTIF Function The SUMIF Function The VLOOKUP Function... 13/14 Further information and solutions to tasks... 15

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5 Status bar statistics The status bar is located at the bottom of the Excel window. This is where Excel displays basic statistical information about your data, without the need to create a formula. All you need to do is select the range that contains your data. In the following example you will find out statistical information about body measurements of a sample of 20 male patients. 1. Move to the Status Bar Statistics worksheet. 2. Select the cells holding the weight for each patient and look down at the status bar, located at the bottom of your screen (to the right). You will see the average weight, the number of cells (Count) included in the selected range and the total weight (Sum) of all 20 men. To display the smallest and largest value You can also display the smallest (minimum) and largest (maximum) value on the status bar. 1. Position mouse over the status bar and right click. TASK: Use the status bar statistics to find the following information: What is the average age? What is smallest and largest hip measurement? What is the height of the shortest man and the tallest man? Answers in back of workbook. 1 Updated 16/12/15

6 Introducing functions Excel functions are predefined formulas. A function has a specific order, called a syntax, which must be strictly followed for the function to work correctly. All functions begin with an equals sign = Followed by the function name (e.g. SUM) Followed by an opening parenthesis, then the argument (cell range or cell reference) and a closing parenthesis. You can have more than one argument, which you separate using a comma. function name arguments function name 2 arguments (separated by comma) equals sign =SUM(A2:D2) equals sign =SUM(A1:A20,C1:C20) Excel has hundreds of functions, which are organised into categories. The functions covered in this workbook are listed below. Category Function What the function does Statistical AVERAGE Calculates the average (arithmetic mean) for a range of cells. COUNTIF MIN MAX MEDIAN Counts the number of cells in a range that satisfy the given criteria. Returns the lowest value in a range of cells. Returns the highest value in a range of cells. Returns the median of the given numbers. MODE.SNGL Returns the most frequently occurring, or repetitive value in an array or range of cells. STDEV.S Math & Trig SUM SUMIF Estimates standard deviation based on a sample. Adds all the numbers in a range of cells. Adds the cells specified by the given criteria. Logical IF Tests a cell to see if the condition specified is true or false. Lookup & Reference VLOOKUP HLOOKUP Looks for a value in the leftmost column of a table, and then returning a value in the same row from a column you specify. Looks for a value in the top row of a table or array of values and returns the value in the same column from the row you specify. 2 Updated 16/12/15

7 Copying formulas Before we start to use functions, you need to know how to copy a formula from one cell to another. In the following example you will copy (using different methods) a formula that adds and a formula that calculates an average, from one cell to many cells. Using the Fill handle to copy a formula 1. Move to the Copy Formulas worksheet, then click into cell B11. B11 holds a formula using the SUM function, which totals the expenditure for January. The formula is shown on the formula bar. 2. Position the mouse pointer over the fill handle at the bottom right of the cell. The pointer will change into a solid black cross. 3. Press the left mouse button and drag across to column M and release. The expenditure for each month will now be summed. Other methods 1. Click into cell B12. B12 holds a formula using the AVERAGE function, which calculates the average expenditure for January. The formula is shown on the formula bar. 2. Select cells B12:M12 (you can use your mouse or keyboard). Keyboard shortcuts: Ctrl+R (fills right) Ctrl+D (fills down) You can also use Copy and Paste, either from the Home ribbon or keyboard shortcuts Ctrl+C and Ctrl+V. TASK: Use the Fill handle to copy the formula from cell N2 down to N10. TASK: Use either the Fill menu or keyboard shortcut to copy the formula from cell O2 down to O10. 3 Updated 16/12/15

8 The SUM and AVERAGE functions The functions in Excel can be accessed in several ways. The exercises in this workbook will use each method, so you become familiar with them. You can then choose your preferred method. Functions can be accessed via the AutoSum list (Home ribbon), the Formulas ribbon, the Insert Function fx button (on Formula bar and Formulas ribbon). Keyboard shortcut: Shift+F3 In the following example you will use the SUM and AVERAGE functions to calculate the totals and averages for data about climate. You will access these functions via the Home ribbon. 1. Move to the SUM and AVERAGE worksheet and click into cell B Click the Home tab, then click AutoSum, located in the Editing group. Cell range B3:B14 will be selected. 3. Click the tick located on the formula bar or press Enter. Note: If you go wrong when inserting a function, click the Cancel button located on the formula bar. 4. Copy the formula across to cell K15. The rainfall and temperature for each country will now be summed. Note: Total temperature is not useful information, so you could delete the formulas in cells C15, E15, G15, I15 and K Click into cell B16, click the Home tab, then click the arrow to the right of the AutoSum button. This lists the most commonly used functions. 6. Choose Average from the list of available functions. Be careful, can you see Excel wants to include the Total Rainfall (B15) in the calculation. You need to re-select cells B3:B14. This cell selection is incorrect This cell selection is correct Now click the tick located on the formula bar or press Enter. 7. Copy the formula from B16 across to cell K16. TASK: Using the same worksheet, calculate the total and averages for crimes reported in England & Wales. Copy the formulas across. TASK: Calculate the total and averages for robbery and copy the formulas down to the remaining cells. 4 Updated 16/12/15

9 The MAX and MIN functions Excel functions are organised in categories. Many of the functions you will need are from the Statistical category. AVERAGE, MAX and MIN are statistical functions and they can be accessed (as in the previous exercise) via the AutoSum button. The MIN function finds the smallest value and MAX finds the highest value. The following data shows body fat and body size measurements for a sample of 20 men. You will use some statistical functions to analyse this data. The next two examples cover the MIN, MAX, MODE.SNGL, MEDIAN and STDEV.S functions. 1. Move to the Statistical Functions worksheet and click into cell B Click the Home tab, then click the arrow to the right of the AutoSum button. Choose Min from the drop down list. Cell range B6:B25 will Note: If you go wrong when inserting a function click the Cancel button located on the formula bar. be selected. 3. Click the tick located on the formula bar or press Enter. This will return the smallest value in column B (5.1). 4. Move to cell B27 and repeat step 2, replacing Min with the Max function, to find the highest This cell selection is incorrect This cell selection is correct value in column B (28.1). Be careful because Excel will try to include B26 in the calculation. You will need to re-select the data to exclude cell B26. TASK: Move to cell B38 and use the MIN and MAX functions to calculate the lowest and highest sale for the month of January. Copy the formulas across to the 5 Updated 16/12/15

10 Calculating mode, median and standard deviation MODE.SNGL, MEDIAN and STDEV.S are also statistical functions. The MODE.SNGL returns the most frequently occurring or repetitive number in a range of cells. MEDIAN returns the number in the middle of a specified range and STDEV.S estimates standard deviation. Find out more For related mathematical resources, go to the Study Hub: Online (BREO community) and refer to Analysing Small Data Sets in the Data Analysis folder in the Maths, Statistics and Excel section. In the following example you will use the MODE.SNGL, MEDIAN and STDEV.S functions to further analyse the body fat and body size measurements. This time you will access the functions via the Insert Function fx button located on the formula bar. 1. Continue to use the Statistical Functions worksheet. Starting in cell B28 click the fx button, located on the formula bar. The Insert Function dialog box will be displayed. Keyboard shortcut: Shift+F3 2. Choose Statistical from the Or select a category: list and MODE.SNGL from the Select a function: list, then click OK. The Function Arguments dialog box will be displayed. The MODE.SNGL and MODE.MULT functions both find the statistical mode. The difference between the two functions is that the MODE.SNGL will only return one mode, ignoring any additional occurring values. The MODE.MULT function is entered as an array formula and will return as many modes as required. Ask your trainer to demonstrate entering an array formula. Note: If there are no repeating numbers (no mode) the error message #N/A will be displayed. TASK: TASK: Use the MEDIAN and STDEV.S functions to calculate the median and standard deviation for the same data. Access the functions via the Insert Function fx button on the formula bar, or the keyboard shortcut: Shift+F3 Copy the formulas from cells B28, B29 and B30 across to the remaining columns. 6 Updated 16/12/15

11 Using the CORREL function The CORREL function returns a correlation coefficient, measuring the linear relationship between two sets of variables. A correlation coefficient has a value range of 1 to 1. A value close to 1 indicates a strong positive linear correlation; so when one variable increases so does the other. A value close to -1 indicates a negative linear correlation. The following data shows the blood pressure and age of 15 patients. Calculating the correlation coefficient will measure if there is a linear relationship between age and blood pressure. Does blood pressure increase with age? You will access the CORREL function via the Formulas ribbon. 1. Move to the Correlation worksheet and click into cell A Click the Formulas tab, choose More Functions, Statistical and then CORREL. The Function Arguments dialog box will be displayed. 3. Click into the Array 1 box and select cell range B2:B16 (age x). Click into the Array 2 box and select cell range C2:C16 (systolic blood pressure y), then click OK. Other Linear Regression Functions INTERCEPT - calculates the point at which a line will intercept the y-axis by using a best-fit regression line plotted through the known x- values and y-values. SLOPE - returns the slope of the linear regression line through the given data points. LINEST - returns statistics that describe a linear trend matching known data points, by fitting a straight line using the least squares method. Other useful functions: TREND and FORECAST. You should get TASK: Using the same worksheet, use the CORREL function to return a correlation coefficient for the data showing birth weight and gestation. You should get a correlation coefficient of which indicates a positive linear correlation. 7 Updated 16/12/15

12 The FREQUENCY function This is a statistical function that returns a frequency distribution. This function requires a set of values (the data) and the intervals (known as bins). It counts the number of values that occur in each interval. Frequency distribution is also available from the Data Analysis Tools in Excel. Find out more For related mathematical resources, go to the Study Hub: Online (BREO community) and refer to Analysing Larger Data Sets in the Data Analysis folder in the Maths, Statistics and Excel section. In the following example you will use the FREQUENCY function to analyse a set of exam results for 80 students (scored out of 100). You will access the FREQUENCY function from the Insert Function fx button located on your formula bar. 1. Move to the Frequency worksheet and select cell range B13:B22 as shown. Selecting empty cells does seem strange, but this is an array formula and if this range is not selected before you start the formula, the results will not be displayed. 2. Click the Insert Function fx button located on the formula bar. The Insert Function dialog box will be displayed. You may need to move it to one side. 3. Choose Statistical from the Or select a category: box and FREQUENCY from the Select a function: list, then click OK. The Function Arguments dialog box will be displayed. 4. Click into the Data_array box and select cell range A6:P10 (the exam results). Click into the Bins_array box and select cell range A13:A22 (the intervals). Important: do not click OK. 5 Press Ctrl Shift Enter on your keyboard. The frequency distribution will be displayed. TASK: Use the FREQUENCY function to create a frequency distribution for survey results on cars per household. 8 Updated 16/12/15

13 The IF function The IF function belongs to Excel s group of logical functions. It tests a condition in a cell has been met, returning one value if the condition is TRUE and another if it is FALSE. Once you understand how the IF function works, you will find many ways you can use it. In the following example you will use the IF function to enter the appropriate text into a range of cells, to indicate if a student has passed or failed an exam. You will access the IF function via the Formulas tab. If an exam score is greater than or equal to 75, the text Pass is displayed. If an exam score is less than 75, the text Fail is displayed. 1. Move to the IF Function worksheet and click into cell C2. 2. Click the Formulas tab, then click Logical, located in the Function Library group and choose IF. The Function Arguments dialog box will be displayed. 3. Click cell B2 (score for Robert), and enter >=75. B2>=75 will appear in the Logical_test box. This is the logical test. Has the student scored 75 or more? 4. Click into the Value_if_true box and type Pass. Click into the Value_if_false box and type Fail, then click OK. You will notice quote marks appear around the word Pass and Fail If you choose to Comparison operators > greater than < less than >= greater than or equal to <= less than or equal to <> not equal to type the formula instead of accessing the function from the ribbons or formula bar, you will need to include the quote marks. TASK: Using the same worksheet, use the IF function to calculate the percentage of discount to be given to customers. If a customer orders more than 100 items, 15% discount is given. If a customer orders less than 100 items, 10% discount is given. 9 Updated 16/12/15

14 Using the IF function with a cell reference Important: The next exercises include absolute referencing and named ranges. If you are not familiar with these topics, they are covered in the Understand Formulas workshop. The following example is the same as the task at the bottom of the previous page, except you will use cell references instead of typing the percentage. You will need to make the cells holding the percentages absolute. You will access the IF function via the Insert Function fx button on the formula bar. If a customer orders more than 100 items,15% discount is given. If a customer orders less than 100 items, 10% discount is given. 1. Move to the IF Function (2) worksheet and click into cell C2. Click the Insert Function fx button located on the Formula bar. The Insert Function dialog box will be displayed. 2. Choose Logical from the Or select a category: list and IF from the Select a function: list, then click OK. The Function Arguments dialog box will be displayed. 3. Click cell B2 and type >100. B2>100 will appear in the Logical_test box. This is the logical test. Has the customer order more than 100 items? Click into the Value_if_true box, then click into cell A8 (15%) and press F4 once to make it absolute. Click into the Value_if_false box, then click into cell A9 (10%) and press F4 once to make it absolute, then click OK. 4. Copy the formula down to display the discount for each order number. Orders over 100 should get 15% discount. Using cell references in the formula will make it easier to manage your worksheet. For example, if you want to change a discount amount, you need only to change one cell. An IF statement can also includes calculations and other functions. TASK: Use the IF function and absolute references to enter the appropriate text into cells C16:C21. If an exam score is greater than or equal to 75, "Pass" is displayed. If an exam score is less than 75, "Fail" is displayed. 10 Updated 16/12/15

15 The COUNTIF function COUNTIF is a statistical function. This function checks a range of cells and counts how many cells meet criteria you specify. The worksheet in the following example contains car sales data. You will use the COUNTIF function to count how many cars have been sold with Bluetooth. You will access the COUNTIF function from the Insert Function fx button located on the formula bar. 1. Move to the Car Sales worksheet and click into cell J3. 2. Access the COUNTIF function via the Insert Function fx button, located on the Formula bar. COUNTIF is a Statistical function. If you have accessed the COUNTIF function correctly, the COUNTIF Function Arguments dialog box will be displayed. 3. Select cell range F3:F32. This is the range of cells from which the function will count. You may need to move the Function Arguments dialog box to one side. 4. Click into the Criteria box, then click into cell I3 (Bluetooth). Cell I3 holds the criteria the COUNTIF function will use when it counts. In this example Bluetooth has been entered into cell I3. 5. Click OK. There are 15 cars with the Bluetooth optional extra. You can enter a different optional extra into cell I3 and the COUNTIF function in cell J3 will recount. In the above example you entered the COUNTIF function into just one cell. Cell I3 was then updated with an alternative optional extra. It would make more sense to see a breakdown of all the optional extras in one table. This is possible if your COUNTIF formula includes absolute cell references. You can then copy the formula to other cells on your worksheet. The example on the next page introduces the SUMIF using absolute cell references. TASK: Using the same worksheet, use the COUNTIF function in cell J6 to count how many red cars have been sold. 11 Updated 16/12/15

16 The SUMIF function SUMIF is a Maths & Trig function. This function allows you to sum a selection of cells depending on criteria you specify. In this exercise you will use the SUMIF function to total the sales of a selection of cars. You will access this function from the Formulas ribbon. 1. Continue to use the Car Sales worksheet and click into cell J9. 2. Access the SUMIF function via the Formulas ribbon. SUMIF is a Math & Trig function. If you have accessed the SUMIF function correctly, the SUMIF Function Arguments dialog box will be displayed. 3. Select cell range D3:D32 and press F4 once to make the range absolute. This is the range of cells (makes of car) to be evaluated by the criteria specified in cell I9. 4. Click into the Criteria box, then click into cell I9. The SUMIF function will only sum the cells that match the make of car (Mercedes) entered into cell I9. 5. Click into the Sum_range box and select cell range G3:G32, then press F4 once to make the range absolute. Click OK. G3:G32 is the range of cells to be summed, based on the criteria specified in cell I9 (in this case, Mercedes). The total sales for the Mercedes is Why make some ranges absolute? You will copy the formula from cell J9 down to the cell J20 to total the remaining cars. This why the cell references in Range and Sum_range are made absolute F4. 6. Copy the SUMIF function from cell J9 down to the J20. You will now have the total sales for each car. TASK: Using the same worksheet, use the SUMIF function to total the sales for each optional extra and/or customers by gender. 12 Updated 16/12/15

17 The VLOOKUP function Lookup functions are used to look up and extract data from a table. The VLOOKUP searches vertically down a sorted data table looking for a match with the lookup-value. It then looks across the table to the column you have specified, to find the value to return. There is also a HLOOKUP function which searches a horizontal table. HLOOKUP - searches a horizontal table VLOOKUP - searches a vertical table In the following example you will use the VLOOKUP (the vertical lookup) function to look up students grades from a table. You will access the VLOOKUP function from the Formulas ribbon. 1. Move to the VLOOKUP worksheet and click into cell C Click the Formulas tab, then click Lookup & Reference, located in the Function Library group and choose VLOOKUP. If you have accessed the VLOOKUP function correctly, the Function Arguments dialog box will be displayed. 3. Click into cell B10 (the cell that holds the mark for Pearl). 4. Click into the Table_array box, select cell range A2:B7 (table that holds grades) and press F4 once. The range A2:B7 (grades table) is made absolute so the VLOOKUP formula can be copied to other cells in your worksheet. Alternatively, you can create a name for the grades table. This also ensures the VLOOKUP formula can be easily copied to other cells in your worksheet, with the added advantage of making the formula easier to understand. 5. Click into the Col_index_num box and enter 2 (column holding grades), then click OK. The grade from Pearl will be displayed in cell C Copy the formula from cell C10 down to C28. TASK: Using the same worksheet. Use the VLOOKUP function to assign the correct commission to each salesperson. 13 Updated 16/12/15

18 The VLOOKUP function In the following example you will enter customer orders into an invoice. The VLOOKUP function will look up the product description and price from a products table (sorted by product code). You will access the VLOOKUP using your preferred method. First you will define a name for the products table shown. This is an alternative to making the table absolute. The product codes are sorted A to Z 1. Move to the Invoice worksheet and select cells G5:I11 (cells holding product data), click the Formulas tab, then click Define Name located in the Defined Names group. 2. Enter product_table into the Name: box and click OK. Cell range G5:I11 is now known as product_table. Spaces are not permitted and are replaced by an underscore _. The name product_table will replace the cell references G5:I11 in the following VLOOKUP formula. 3. Click into cell B4, access the VLOOKUP function using your preferred method, then click into cell A4 (first product code). 4. Click into the Table_array box and type product_table. 5. Click into the Col_index_num box and type 2, then click OK. Column 2 of the Product Table holds the product descriptions. The product description for product code A300 is conditioner. If you change the product code the correct description will be displayed. 6. Copy the formula down to cell B8. 7. Click into cell D4 and use the VLOOKUP to insert the correct price, then copy the formula down to cell D8. Important: the product prices are in column 3. Enter 3 into the Col_Index_num box. TASK: Move to the HLOOKUP worksheet. Use the HLOOKUP function to return information about the rooms for each property type. 14 Updated 16/12/15

19 Formulas and Functions Further information and solutions to tasks Computer Skills Training Workshops This is just one of a number of workshops we offer to students throughout the academic year. To get the most of our workshops: Browse the workshop content (on BREO or LRweb) to ensure it meets your needs. Be aware that our advanced workshops are delivered at a faster pace; make sure you are confident using the software before attending an advanced workshop. Level Excel workshops Word workshops PowerPoint workshops Beginner Excel fundamentals Word fundamentals PowerPoint fundamentals Intermediate Create charts Format your assignment Animated slideshows Understand formulas Format your dissertation Create posters using PowerPoint Advanced Work with functions Manage your dissertation Use Excel to analyse data Find out more For related mathematical resources go to Study Hub: Online (BREO Community) and refer to the resources in the Maths, Statistics and Excel section. Task solutions: Pg 1 average age 27.6 smallest hip measurement 94.5 largest hip measurement shortest man tallest man