Pricing Tab (ACBC)
ACBC studies often include a price attribute (though one is not required). Price attributes can be specified as a "standard" attribute with specific price levels to use (such as might be done in an ACA survey). The price attribute can also be applied as a continuous variable, selected based on the sum of a base price plus level-based prices (and perturbed by random variation).
For more information on the use of price in ACBC, see the section entitled, Price in Adaptive CBC.
Base Price: You specify a base price that applies to all products (irrespective of levels defining that product). When the BYO question is displayed, the initial total price shown is initialized at the base price. For other questions in the ACBC survey, summed prices always include the base price for every product concept.
Vary prices from ____% above summed price to _____% below summed price: When using summed pricing, it's important that you apply enough random variation to the total price shown so as to be able to disassociate the effect of price changes on product choice from the price increments you may have attached to individual price levels. Generally, we recommend varying price by at least +30% to -30% to avoid problems in price estimation, but this decision depends on the size of the base price relative to the size of prices associated with the attribute levels.
The relative price to show is chosen randomly from within the range of price variation you've specified. For example, if your price variation is from +30% to -30%, then a random multiplier in the range of 1.3 to 0.7 is selected and the summed prices for the product concept are multiplied by the price multiplier. For example, if the product concept to be displayed has total summed price (base price plus any level-based prices) of $1,000 and the random price multiplier drawn is 1.14, then the total price shown to respondents is $1,140.
Round to Nearest: Allows you to round the computed price (summed prices times the random price multiplier) to the nearest 0.01, 0.10, 0.50, 1.0, 10, 20, 50, 100, etc. units of price. If less than 1.0, the rounding units specified must evenly divide into 1.0. If greater than 1.0, the rounding units must evenly divide into the tens/hundreds/thousands unit directly larger than the value. For example, 2, 5, 10, 20, 50, 100, 200, 500, 1000, 2000, 5000, etc. So, $12,348 rounded to the nearest $200 would be $12,200. Note that the rounded value is recorded in the data file, rather than the originally computed value.
Add _____ to rounded price: Allows you to adjust the rounded price by a constant. For example, if you want all prices rounded to the nearest $99, you would specify to round to the nearest 100 and add -1 to the rounded price.
To format your prices, you can select the Currency Symbol(s) (and whether to show it before or after the price), the Thousands Separator (usually , or .), whether to Show Decimals, the Decimals Separator (usually . or ,) and Number of Decimals of precision to display (usually 2).
Use Price in Unacceptables: By default, ACBC does not ask respondents for cut-off rules (Unacceptables) regarding "summed" price. But, if you want ACBC to do so, check this box. Then, indicate at which Unacceptables question the respondent will first be asked about an unacceptable price threshold, and the label to use directly before the price value. The price threshold is offered at the highest price ever chosen as "a possibility" in either the Screener or BYO questions.
Level Prices: For each attribute you wish to associate with level prices, select the attribute and type the level prices within the grid. When a product is shown on the screen, its price will be a function of the (base price + level prices) * random price multiplier.
If you specify level prices, the total prices shown for products will be more reasonable. This tends to avoid the possibility of displaying premium products (with high-level features) at cheap prices or vice-versa. The level prices are generally shown to the respondent in the BYO question (when respondents make attribute-by-attribute selections of the preferred level, given the level-based prices). This is treated in the design file as a tradeoff between each level and given prices. The other questions in the ACBC survey provide more observations regarding how respondents tradeoff different levels versus total price. We recommend you use level prices for most ACBC studies involving summed price. For more information regarding selecting level prices and the possible effect on final utility estimation, see the sections entitled Price in Adaptive CBC and Modeling the Price Function.
